Article

Asynchrony of mother-infant hypothalamic-pituitary-adrenal axis activity following extinction of infant responses induced during the transition to sleep

Authors:
  • UC Irvine; Johns Hopkins University
  • Pennsylvania State University Worthington Scranton, Dunmore, PA
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... Ramos and Youngclarke [31] analyzed advice on bed sharing (not recommended beyond the first few months of life to prevent the risk of Sudden Infant Death Syndrome, SIDS) [32,33] and the extinction method (recommended for treating behavioral insomnia) [34][35][36] in 40 English-language self-help books on children's sleep. One out of three books (n=11; 28%) promotes bed sharing and one out of three books (n=12; 30%) rejects the extinction-based learning method. ...
... Behavioral techniques: Experts recommend empiricallyvalidated sleep learning methods: complete extinction [34][35][36], graduated extinction [48][49][50][51] and reducing parental presence [52,53]. Of the 19 self-help books that mention using behavioral techniques to treat insomnia, 63% are compliant with expert advice by recommending (n=12) this practice. ...
... Indeed, few self-help books do mention it, a large number of authors oppose it, some authors do not take sides and some others propose alternative methods that have not been empirically validated. However, the scientific literature advocates interventions that support sleep onset independence, which is the learning method recommended by experts with the largest amount of evidence [34][35][36]. Our study shows that many self-help books are not compliant with expert recommendations on these criteria, often stating that children should not be left to cry. ...
Article
The present study aims to assess the quality of self-help books on the subject of children’s sleep. Method: An international committee of specialized pediatricians and psychologists established 37 criteria in terms of quality and recommendations on children’s sleep development and treatment for sleep disorders. Thirty-three self-help books written in French language were assessed on exhaustiveness regarding quality criteria and on authors’ compliance with expert advice. Results: Half of the authors had no health care qualifications, the other half were health professionals. A few authors were specialists in sleep. Nearly 82% self-help books were not exhaustive. Only 15% of all the self-help books in the sample were more than 50% compliant with expert advice. One-third of self-help books obtained higher than a 50% total weighted score combining exhaustiveness and compliance with the criteria. The majority of self-help books do not mention at all the following criteria: risk of sudden infant death syndrome (SIDS), recommended methods for treating insomnia, and the impact of screens on sleep. Conclusion: The heterogeneity of self-help books raises questions about the appropriateness of their proliferation: readers have a 50/50 chance of reading a book that follows expert advice, and those who read two books have a high risk of encountering conflicting advice. This variability and the lack of legitimacy of some of the authors to publish health recommendations are detrimental to the cause of preventive health, as well as to guiding parents seeking a care solution for their children with sleep disorders.
... 11 Nighttime separation from the mother in infants as old as 10 months can cause infant distress and elevated cortisol levels, even if the infant does not appear outwardly distressed. 12 Furthermore, although nighttime separation during the first 4 months may be associated with longer periods of sleep consolidation in the infant 13 and decreased night-time awakenings, 14 this may not be physiological or safe, and partially explain why sleeping in proximity to the mother is associated with a decreased risk of sudden infant death syndrome (SIDS). 15 Differences in sleep patterns may vary according to race/ethnicity as well as maternal education and household income. ...
... Proximate mother-infant sleep allows the mother to be immediately responsive to the infant, as demonstrated in physiological studies. 12,49 Mothers and infants are both more arousable, 49,50 and the mother forms a protective circle around the infant with her arms and legs, as her arm blocks the pillow from the infant (known as the C-position or ''cuddle-curl'' 51 ). The infant's head is alongside the mother's breast, and after feeding the infant rolls onto their back, as bedsharing breastfeeding infants would not naturally sleep prone. ...
... 76,77 Training young infants to sleep alone by failing to respond to their crying in a distant crib causes significant infant stress, as indicated by elevated infant cortisol levels, which persist on the nights when the infant is no longer crying. 12 Parents often experience distress at not responding to their infant's cries, 78,79 and often find sleep training is not effective. 79 Objective measures of infant sleep outcomes do not find that these methods ''improve'' the sleep of the infants who undergo this training. ...
Article
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A central goal of the Academy of Breastfeeding Medicine (ABM) is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient. The ABM empowers health professionals to provide safe, inclusive, patient-centered, and evidence-based care. Pregnant and lactating people identify with a broad spectrum of genders, pronouns, and terms for feeding and parenting. There are two reasons ABM's use of gender-inclusive language may be transitional or inconsistent across protocols. First, gender-inclusive language is nuanced and evolving across languages, cultures, and countries. Second, foundational research has not adequately described the experiences of gender-diverse individuals. Therefore, ABM advocates for, and will strive to use language that is as inclusive and accurate as possible within this framework. For more explanation, please read ABM Position Statements on Infant Feeding and Lactation-Related Language and Gender (https://doi.org/10.1089/bfm.2021.29188.abm) and Breastfeeding As a Basic Human Right (https://doi.org/10.1089/bfm.2022.29216.abm).
... However, cortisol was not measured at the time of separation (when parents feel the urge to comfort their child) but considerably later. Only Middlemiss et al. (2012) measured cortisol at the moment of separation in an extinction protocol, finding prolonged and elevated cortisol in infants in their sample. In another study, Middlemiss et al. (2017) reported actively responding and settling during BSI, showing no cortisol elevation. ...
... It is necessary to better understand stress and depression levels during different types of BSI that utilise different levels of responsiveness. Measuring maternal stress levels objectively has been undertaken and may be beneficial (Gradisar et al. 2016;Middlemiss et al. 2012), but even subjective reports of their own stress and that of their infant can be informative. Measuring infant and maternal stress levels during a bedtime stressor, both objectively and subjectively at the moment of the bedtime separation, and estimations of maternal depression have not been undertaken in a Responsive BSI compared to an extinction protocol. ...
... Multivariate ANOVA general linear models were utilised to evaluate differences in sleep duration and EPDS between groups. Following established protocols (Middlemiss et al. 2012), saliva samples (n = 5) with cortisol values considered biologically implausible (i.e. > 2.0 µg/dL) and three samples with insufficient volume were excluded from analysis. ...
Article
Full-text available
Methods to improve sleep in infants commonly involve some ignoring (extinction) but are often unpopular with mothers worried about infant distress when left to cry. Alternative more responsive methods are needed. This pilot study evaluated stress, maternal depressive symptomology and sleep in mother/infant dyads, between Responsive, Controlled Crying and Control groups. From 199 mother/infant dyads from any cultural background, 41 infants 4–12 months were randomly allocated to Responsive (RG, n = 15), Controlled Crying (CCG, n = 18) or Controls (Treatment as Usual, TAUG, n = 8), with 10 withdrawing after randomisation. Infant sleep (7-day sleep diaries) and stress (oral cortisol on two nights), maternal self-reported stress (Subjective Units of Distress, SUDS), maternal perceived infant distress (MPI-S) and symptoms of maternal depression (Edinburgh Post-natal Depression Scale, EPDS) were measured four times across 8 weeks. Sleep duration was not different between groups but Responsive woke less ( p = .008). There were no differences in cortisol between groups across time points. Maternal SUDS was positively correlated with infant cortisol and MPI-S ( p < 0.05) and mothers in the Responsive group were significantly less stressed ( p = 0.02) and reported less symptoms of depression ( p < 0.05) . Findings in this small sample show Responsive methods are comparable to the extinction (Controlled Crying) in sleep outcomes but from a relational and maternal mental health perspective, are less stressful, offering families potential choices of sleep interventions.
... In den bisherigen Studien wurde hauptsächlich die Effektivität diverser Schlafinterventionen überprüft (Field, 2017;Loutzenhiser, Hoffman & Beatch, 2014;Mindell, Kuhn, Lewin, Meltzer & Sadeh, 2006). Noch zu wenig existieren methodisch ausgereifte Forschungsarbeiten zu den langfristigen Folgen dieser Vorgehensweise (Gradisar et al., 2016;Middlemiss, Granger, Goldberg & Nathans, 2012;Price, Wake, Ukoumunne & Hiscock, 2012). Auch sind die Gründe für eine Anwendung und ihre Verbreitung bisher kaum erforscht worden. ...
... Sie werden häufiger gestillt und erhalten schnellere Reaktionen auf ihre Bedürfnisse (Baddock, 2006 (Dias & Figueiredo, 2019;Keener, Zeanah & Anders, 1988;Sadeh, Lavie & Scher, 1994;Thunström, 2002 (Mindell & Durand, 1993;Mindell et al., 2006;Price et al., 2012). Langfristig gesehen, zeigt Price et al. (2012) (Middlemiss et al., 2012). Extinktion führt demnach zu einer schnelleren Habituation auf der Verhaltensebene des Kindes, jedoch nicht auf der physiologischen Ebene des Kindes, was durch eine anhaltende erhöhte Aktivität der ...
... Graduated extinction instructs parents to partially ignore an infant's crying while trying to fall asleep and to check occasionally on the infant's well-being according to a defined time schedule (Ferber, 1985;Minde et al., 1993;Mindell et al., 2006). Sleep interventions are criticized by some infant mental health experts (Middlemiss et al., 2012;Murray & Ramchandani, 2007), but are very popular among parents, probably as a result of the frequently reported effectiveness of these interventions (Mindell et al., 2006). Behavioral treatments such as unmodified and graduated extinction reduce bedtime problems, at least for a certain period of time (Mindell et al., 2006). ...
... With the increasing sophistication of physiological attunement research, it has become more difficult to house the many facets of the relations between maternal and infant cortisol under the single construct of "attunement," as reviewed by Bernard et al. (2017). One early corollary of an attunement model was that adaptive physiological regulation was defined primarily in terms of a positive correlation between cortisol levels or cortisol trajectories of mothers and infants (Van Bakel & Riksen-Walraven, 2008;Middlemiss et al., 2012;Sethre-Hofstad et al., 2002). However, Nofech-Mozes et al. (2019) cautioned that positive/adaptive physiological regulation does not always mean similar physiology in the mother and infant. ...
... Rather, adaptive regulation depends on the ability of one partner to respond and adjust appropriately to the other, which may mean downregu- Additionally, as Bernard et al. (2017) have cogently reviewed, the many current analytic methods used to characterize the relations between maternal and infant cortisol over time do not index a single process or construct. For example, some studies have focused on correlations between maternal and infant cortisol before and after induced stress (Middlemiss et al., 2012;Thompson & Trevathan, 2008). While the frequently observed positive associations are often interpreted to indicate that mothers influence their infants' cortisol levels, it is equally plausible that infants influence their mothers' cortisol levels. ...
... This effect of MCM is consistent with recent studies that have shown less attunement in motherinfant cortisol levels in less optimal environments (e.g., Bernard et al., 2017). This finding extends previous reports of concurrent associations between maternal and infant cortisol in low-risk samples (Atkinson et al., 2013;Laurent et al., 2012;Middlemiss et al., 2012) by showing that these positive concurrent associations occur primarily in the context of lower MCM. This finding also extends prior work to include the directionality of this effect from mother to infant and not from infant to mother. ...
Article
Full-text available
The relation between maternal and infant cortisol responses has been a subject of intense research over the past decade. Relatedly, it has been hypothesized that maternal history of childhood maltreatment (MCM) impacts stress regulation across generations. The current study employed four statistical approaches to determine how MCM influences the cortisol responses of 150 mothers and their 4‐month‐old infants during the Still‐Face Paradigm. Results indicated that MCM moderated cortisol patterns in several ways. First, lower MCM mothers and infants had strong positive associations between cortisol levels measured at the same time point, whereas higher MCM mothers and infants did not show an association. Second, infants of higher MCM mothers had cortisol levels that were moderately high and remained elevated over the procedure, whereas infants of lower MCM mothers had decreasing cortisol levels over time. Third, higher MCM mothers and infants showed increasingly divergent cortisol levels over time, compared to lower MCM dyads. Finally, patterns of cross‐lagged influence of infant cortisol on subsequent maternal cortisol were moderated by MCM, such that lower MCM mothers were influenced by their infants' cortisol levels at earlier time points than higher MCM mothers. These findings highlight MCM as one contributor to processes of stress regulation in the mother–infant dyad.
... In terms of time, if cortisol is assessed at more than one time point, statistical attunement might be conceptualized as simultaneous (i.e., associations between mothers and infants at the same time points), or lagged (i.e., one dyad member's cortisol at a previous time point is related to the other member's cortisol at the next time point). In terms of interactive reciprocity, statistical attunement might be conceptualized as mother led (i.e., mother's cortisol impacts infant's cortisol trajectory), infant led (i.e., infant's cortisol impacts mother's cortisol trajectory; Middlemiss et al., 2012), or bidirectional (i.e., mother and infant cortisol impact mother and infant cortisol trajectories). All in all, these many possibilities, and a frequent failure to explicitly recognize them, make it difficult to construct a priori hypotheses regarding which features of attunement will emerge in a given situation. ...
... 2 This is in comparison to the interpretation of slopes within a univariate multilevel model, where slope coefficients do reflect directionality. 3 Of note, these figures depict declining maternal trajectories because mothers typically decline in cortisol during infant stress following anticipatory anxiety (Atkinson et al., 2013;Bernard et al., 2016;Davis & Granger, 2009;Hibel et al., 2009;Laurent et al., 2011;Middlemiss et al., 2012;Sethre-Hofstad, Stansbury, & Rice, 2002;van Bakel & Riksen-Walraven, 2008). In addition, note that we have graphed trajectories using three time points as this is common in the literature (e.g., Atkinson et al., 2013;Hibel et al., 2009), though not without problems (see Bernard et al., 2016). ...
... Although investigators have shown an association between maternal sensitivity and dyadic cortisol attunement, the issue of mother-infant attachment and cortisol attunement has not yet been addressed. This is surprising because hypotheses regarding cortisol attunement (Atkinson et al., 2013;Crockett et al., 2013;Davis & Granger 2009;Hibel et al., 2009;Middlemiss et al., 2012) are often based on findings that behavioral attunement (Isabella & Belsky, 1991) and cortisol secretion (e.g., Hertsgaard, Gunnar, Erickson, & Nachmias, 1995;Luijk et al., 2010) are associated with mother-infant attachment. Ainsworth, Blehar, Waters, and Wall (1978) identified three attachment classifications based on mother-infant interactions during the Strange Situation Procedure (SSP). ...
Article
This study explores the conceptualization of mother–infant cortisol attunement both theoretically and empirically, and its association with mother–infant attachment disorganization. In a community sample ( N = 256), disorganization and cortisol were assessed during the Strange Situation Procedure (SSP) at infant age 17 months. Salivary cortisol was collected at baseline, and 20 and 40 min after the SSP. We utilized three statistical approaches: correlated growth modeling (probing a simultaneous conceptualization of attunement), cross-lagged modeling (probing a lagged, reciprocal conceptualization of attunement), and a multilevel model difference score analysis (to examine the pattern of discrepancies in mother–infant cortisol values). Correlated growth modeling revealed that disorganized, relative to organized, dyads had significant magnitude of change over time, such that, among disorganized dyads, as mothers had greater declines in cortisol, infants had greater increases. The difference score analysis revealed that disorganized, relative to organized, dyads had a greater divergence between maternal and infant cortisol values, such that maternal values were lower than infant values. Disorganized attachment status was not significantly associated with attunement when conceptualized as reciprocal and lagged in the cross-lagged model. Findings suggest that mother–infant dyads in disorganized attachment relationships, who are by definition behaviorally misattuned, are also misattuned in their adrenocortical responses.
... Similarity between two people's hypothalamic-pituitary-adrenal (HPA) axis activity, known as adrenocortical attunement (and also called adrenocortical synchrony or concordance), has been well-documented between romantic relationship partners (Papp et al., 2013;Saxbe and Repetti, 2010;Schreiber et al., 2006), between parents and children (Atkinson et al., 2013;Hibel et al., 2015;Sethre-Hofstad et al., 2002;van Bakel and Riksen-Walraven, 2008), and between close friends (Rankin et al., 2018). Adrenocortical attunement been associated with a range of processes in close relationships, including time spent together (Papp et al., 2009(Papp et al., , 2013, negative affect and distress (Middlemiss et al., 2012;Papp et al., 2009), and behavioral sensitivity (Atkinson et al., 2013;Hibel et al., 2015;Sethre-Hofstad et al., 2002;van Bakel and Riksen-Walraven, 2008). ...
... Several studies support the idea that greater access to information about partners-as is revealed during self-disclosure-facilitates adrenocortical attunement. For example, mothers and babies are more attuned to each other during sleep training when mothers can hear their babies cry but not when they do not hear their babies cry (Middlemiss et al., 2012). Spouses tend to be more attuned to each other when they are physically together at home in the early morning and evening-times when they have access to more behavioral cues from their partners (Saxbe and Repetti, 2010)-and when they spend more time together in general (Papp et al., 2013). ...
Article
Adrenocortical attunement—similarity in hypothalamic-pituitary-adrenal (HPA) axis activity—has been well-documented in close relationships (e.g., between romantic partners, parents and children, and close friends). However, little is known about adrenocortical attunement during early relationship formation. In the current study, we examine dyadic adrenocortical attunement during a guided conversation in which two new acquaintances (N = 140 people, 70 dyads), who were university students or adults in the community, answered questions about themselves. Dyads were randomly assigned to answer questions designed to elicit dyad members to reveal a high or low amount of personal information (i.e., to self-disclose at high or low levels). We collected saliva samples (assayed for cortisol) before and after the conversation, and we coded behavioral self-disclosure—the extent to which people revealed their thoughts, feelings, and facts about themselves—during the conversation. As expected, dyads who were assigned to ask and answer high self-disclosure disclosed more than those assigned to ask and answer low self-disclosure questions. In addition, greater self-disclosure during the conversation was associated with greater similarity in cortisol change—that is, dyad members who revealed more about themselves experienced more similar cortisol changes in response to their conversation. This work reveals one social process through which adrenocortical attunement occurs during early relationship formation, and, in doing so, describes how our physiological functioning is linked to those around us—even people we have just met.
... The study of biological attunement, especially in terms of cortisol, has been primarily limited to marital or romantic dyads (Papp, Pendry, Simon, & Adam, 2013) and mother-infant relationships (Hibel et al., 2015;Middlemiss, Granger, Goldberg, & Nathans, 2012), though there have been some studies conducted with mother-adolescent dyads. These investigations have shown similar patterns, with cortisol attunement being more robust among dyads who spend more time together compared to others during disagreements and challenges (Papp, Pendry, & Adam, 2009). ...
... Preliminary evidence has demonstrated links between parent-child interactions and various physiological indicators of well-being. For example, Cui, Morris, Harrist, Larzelere, and Criss (2015) reported that within-dyad positive affect (observed during a disagreement task) was positively related to respiratory sinus arrhythmia (RSA), another index of stress system ac- This suggests that attunement at many developmental points may provide an index of relationship functioning or sensitivity to behavioral cues within the parent-child dyad (Middlemiss et al., 2012). As Saxbe and Repetti (2010) note, adrenocortical attunement cannot accurately be labeled as "bad" or "good" relationship phenomenon, but rather an index of physiological interdependence and how the dyad navigates threats and challenges together. ...
Article
Examining the multitude of influences on the development of adolescent stress responses, especially among low‐income families, is a critical and understudied topic in the field. The current study examined cortisol attunement between adolescent girls and parents (mostly mothers) from predominantly low‐income, single parent, ethnic minority families before and after an in‐laboratory disagreement discussion task. The sample consisted of 118 adolescents (Mage = 13.79 years, 76.3% ethnic minorities, 23.7% European Americans) and primary caregivers (Mage = 40.62 years; Mdn yearly income = $24,000; 43.2% single parents; 50% living below poverty line). We investigated oxytocin receptor (OXTR rs53576) gene variations as a potential contributor to attunement within the dyad. Results showed that parents and adolescents showed stress system attunement across the disagreement task, but that parent and adolescent oxytocin receptor genotype did not impact attunement. Future studies should detail biological factors that contribute to the calibration of stress response systems of adolescents across a variety of samples, particularly those experiencing a combination of stressors.
... Different authors express different theoretical and statistical concepts in their approach to the study of cortisol associations between mother and infant. To give a few examples of the main approaches, this physiological relationship has been described as "physiological (cortisol) attunement" (Atkinson et al., 2013;Crockett et al., 2013;Hibel et al., 2009;Nofech-Mozes et al., 2019;van Bakel and Riksen-Walraven, 2008), "physiological synchrony" (Halevi et al., 2017;Middlemiss et al., 2012;Pratt et al., 2017) or "adrenocortical coregulation" (Ruttle et al., 2011;Saxbe et al., 2015). To avoid misrepresenting subtle meanings regarding the appropriate nomenclature regarding mother-child cortisol correlations, in the present review, we most often refer to mother-infant "cortisol correlations" as "cortisol associations". ...
... In these studies, maternal and infant cortisol measures have been related to one another either at the same time points, or over a given short-or longer-term trajectory (Abraham et al., 2018;Jonas et al., 2018;Middlemiss et al., 2012;Pratt et al., 2017). They may also be compared between mothers and infants in the absence of a known or defined stressor (Jonas et al., 2018), as a response to a structured interaction, a stressor or a challenge task (Atkinson et al., 2013;Hibel et al., 2009;Ruttle et al., 2011;Sethre-Hofstad et al., 2002). ...
Article
This selective review first describes the involvement of the maternal hypothalamic-pituitary-adrenal (HPA) axis during pregnancy and the postpartum period, and the relation between peripartum HPA axis function and maternal behavior, stress reactivity and emotional dysregulation in human mothers. To provide experimental background to this correlational work, where helpful, animal studies are also described. It then explores the association between HPA axis function in mothers and their infants, under ongoing non-stressful conditions and during stressful challenges, the moderating role of mothers' sensitivity and behavior in the mother-child co-regulation and the effects of more traumatic risk factors on these relations. The overarching theme being explored is that the HPA axis - albeit a system designed to function during periods of high stress and challenge - also functions to promote adaptation to more normative processes, shown in the new mother who experiences both high cortisol and enhanced attraction and attention to and recognition of, their infants and their cues. Hence the same HPA system shows positive relations with behavior at some time points and inverse ones at others. However, the literature is not uniform and results vary widely depending on the number, timing, place, and type of samplings and assessments, and, of course, the population being studied and, in the present context, the state, the stage, and the stress levels of mother and infant.
... Regarding the secretion of cortisol (i.e., responses of the hypothalamic-pituitary-adrenal (HPA) axis), in particular, recent studies demonstrated significant correlations between mothers' and their children's salivary cortisol responses to stress and to their dyadic play interactions. Such correlations have been found in infancy (Bright et al. 2012;Middlemiss et al. 2012), in toddlerhood (Atkinson et al. 2013), in preschool age (Ruttle et al. 2011), and even in adolescence (Papp et al. 2009;Saxbe et al. 2014). Further studies, moreover, revealed that mothers' basal salivary cortisol concentration (e.g., Hibel et al. 2014;Middlemiss et al. 2012;Ruttle et al. 2011) and their accumulated, long-term cortisol secretion [as captured by the hair cortisol concentrations (HCC)] are associated with those of their children (Flom et al. 2017;Liu et al. 2017;Ouellette et al. 2015). ...
... Such correlations have been found in infancy (Bright et al. 2012;Middlemiss et al. 2012), in toddlerhood (Atkinson et al. 2013), in preschool age (Ruttle et al. 2011), and even in adolescence (Papp et al. 2009;Saxbe et al. 2014). Further studies, moreover, revealed that mothers' basal salivary cortisol concentration (e.g., Hibel et al. 2014;Middlemiss et al. 2012;Ruttle et al. 2011) and their accumulated, long-term cortisol secretion [as captured by the hair cortisol concentrations (HCC)] are associated with those of their children (Flom et al. 2017;Liu et al. 2017;Ouellette et al. 2015). ...
Article
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Associations between mothers’ and children’s cortisol secretion parameters are well established. According to the bio-behavioral synchrony model, these associations reflect influences of the mother–child relationship, the child’s social adjustment, and might also reflect shared genetic dispositions. From the bio-behavioral synchrony model, we predicted a stronger mother–child hair cortisol concentration (HCC) link in mothers showing highly adequate (compared to those showing less adequate) parenting behaviors and in children showing low (compared to those showing high) ADHD symptoms. From a genetic perspective, no such moderator effects, or a stronger mother–child HCC link in children with high ADHD symptoms, can be expected. The study sample consisted of 111 4–5-year-old children (64 of whom screened positive for increased ADHD symptoms) and their mothers. ADHD symptoms were assessed by a clinical interview and parent and teacher questionnaires. Maternal sensitive/responsive parenting behavior was assessed by an at-home behavior observation procedure. In mothers and children, HCC in the most proximal 3-cm scalp hair segment was analyzed using luminescence immunoassay. Overall HCCs of mothers and their children correlated significantly. Maternal sensitivity/responsiveness and child ADHD symptoms proved to be significant moderator variables of this association: High maternal sensitivity/responsiveness and low ADHD symptoms of the child were associated with a stronger mother–child link in HCC. The findings are in line with the bio-behavioral synchrony model in the mother–child relationship, and are less compatible with a genetic perspective. The results might hint at environmental events influencing the development of stress axis functioning in subgroups of preschoolers with high ADHD symptoms.
... Graduated extinction instructs parents to partially ignore an infant's crying while trying to fall asleep and to check occasionally on the infant's well-being according to a defined time schedule (Ferber, 1985;Minde et al., 1993;Mindell et al., 2006). Sleep interventions are criticized by some infant mental health experts (Middlemiss, Granger, Goldberg, & Nathans, 2012;Murray & Ramchandani, 2007), but are very popular among parents, probably as a result of the frequently reported effectiveness of these interventions (Mindell et al., 2006). Behavioral treatments such as unmodified and graduated extinction reduce bedtime problems, at least for a certain period of time (Mindell et al., 2006). ...
... Although research cannot clearly say whether ICBC has long-term consequences for an infant's mental health, it could be assumed that offering no response to a baby's cry, as with ICBC, might actually harm a child. The child could stop crying, but a noncrying child also can experience psychological and physiological stress, as has been demonstrated in squirrel monkeys who changed their behavior independently of their physiological arousal (Coe, Glass, Wiener, & Levine, 1983), as well as in humans (Middlemiss et al., 2012). It also has been shown that answering infants' crying within the first minute and adequate maternal responsiveness at bedtime are associated with lower infant cortisol levels across the night (Philbrook et al., 2014). ...
Article
Ignoring children's bedtime crying (ICBC) is an issue that polarizes parents as well as pediatricians. While most studies have focused on the effectiveness of sleep interventions, no study has yet questioned which parents use ICBC. Parents often find children's sleep difficulties to be very challenging, but factors such as the influence of Western approaches to infant care, stress, and sensitivity have not been analyzed in terms of ICBC. A sample of 586 parents completed a questionnaire to investigate the relationships between parental factors and the method of ICBC. Data were analyzed using structural equation modeling. Latent variables were used to measure parental stress (Parental Stress Scale; J.O. Berry & W.H. Jones, 1995), sensitivity (Situation-Reaction-Questionnaire; Y. Hänggi, K. Schweinberger, N. Gugger, & M. Perrez, 2010), Western-oriented parental beliefs (Rigidity), and children's temperament (Parenting Stress Index; H. Tröster & R.R. Abidin). ICBC was used by 32.6% (n = 191) of parents in this study. Parents' Western-oriented beliefs predicted ICBC. Attitudes such as feeding a child on a time schedule and not carrying it out to prevent dependence were associated with letting the child cry to fall asleep. Low-sensitivity parents as well as parents of children with a difficult temperament used ICBC more frequently. Path analysis shows that parental stress did not predict ICBC. The results suggest that ICBC has become part of Western childrearing tradition.
... Physiological attunement reflects the idea that maternal and infant physiological systems, including the HPA axis, are in sync (Bright, Granger, & Frick, 2012;Hibel, Granger, Blair & Finegood, 2015;van Bakel & Riksen-Walraven, 2008). Indeed, it is well established that maternal and infant basal and diurnal cortisol levels are related (Benjamin Neelon, Stroo, Mayhew, Maselko, & Hoyo, 2015;Bright et al., 2012;Clearfield, Carter-Rodriguez, Merali, & Shober, 2014;Fuchs, Möhler, Resch, & Kaess, 2016;Middlemiss, Granger, Goldberg, & Nathans, 2012;Spangler, 1991;Stenius et al., 2008). Physiological attunement has been suggested to have evolutionary roots, as it is adaptive for mothers and infants to pick up on each other's cues to external risk, resulting in attuned physiological stress. ...
... Results highlight the importance of day-to-day maternal cortisol regulation for infant physiological development. This is the first study to show that postnatal maternal cortisol predicts two distinct aspects of infant physiology and suggests a potential role of maternal slope as a biomarker of infant physiological regulation broadly construed.The longitudinal relation between 6-month maternal slope and 12-month infant slope builds on past research showing maternal and infant cortisol are concurrently related(Benjamin Neelon, Schou Andersen, et al., 2015;Bright et al., 2012;Clearfield et al., 2014;Laurent, Ablow, & Measelle, 2012;Middlemiss et al., 2012;Stenius ...
Article
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Physiological stress systems and the brain rapidly develop through infancy. While the roles of caregiving and environmental factors have been studied, implications of maternal physiological stress are unclear. We assessed maternal and infant diurnal cortisol when infants were 6 and 12 months. We measured 12-month infant electroencephalography (EEG) 6–9 Hz power during a social interaction. Steeper 6-month maternal slope predicted steeper 12-month infant slope controlling for 6-month infant slope and breastfeeding. Steeper 6-month maternal slope predicted lower 6–9 Hz power. Six-month maternal area under the cuve (AUCg) was unrelated to 12-month infant AUCg and 6–9 Hz power. Psychosocial, caregiving, and breastfeeding variables did not explain results. At 6 months, maternal and infant slopes correlated, as did maternal and infant AUCg. Twelve-month maternal and infant cortisol were unrelated. Results indicate maternal slope is an informative predictor of infant physiology and suggest the importance of maternal physiological stress in this developmental period. K E Y W O R D S diurnal cortisol, EEG power, infant, physiological attunement, slope
... Such babies may be medicalised (Douglas and Hill 2011), medicated (Owens et al. 2003), punished and, in extreme cases, abused (Reijneveld 2002) for displaying speciestypical infant behaviour, that is waking at night, frequent night-feeding, and crying when left alone (Ball 2013;Ball and Russell 2012). Increasingly babies are subjected to clinic-based (Australia) or parentally imposed (US) sleep-training programmes from an early age (Blunden et al. 2011;Douglas and Hiscock 2010;Hiscock et al. 2007;Mindell et al. 2006), a practice that is not only controversial but developmentally inappropriate for young infants (Blunden et al. 2011) and potentially harmful for parent-infant well-being by increasing maternal anxiety, prematurely terminating breastfeeding, increasing the risk of sudden infant death syndrome (SIDS), increasing infant crying and potentially decoupling maternal-infant physiological synchrony (Douglas and Hill 2013;Middlemiss et al. 2012;Whittingham and Douglas 2014). ...
... Nevertheless, some studies suggest that this physiological co-regulation could be the physiological result of the dyad's shared experiences (Feldman, 2007;Papp et al., 2009). What Hibel et al. observed is that adrenocortical synchrony is moderated by both members of the dyad, for it depends on both maternal sensitivity and the child's emotional reactivity (as documented in Middlemiss et al., 2012;Atkinson et al., 2013). For this reason, maternal depression, which can undermine maternal sensitivity, is associated with less optimal child stress response and developmental outcomes (Feldman et al., 2009;Barker et al., 2011;Laurent et al., 2011;Apter-Levi et al., 2016;Granat et al., 2017;Pratt et al., 2019). ...
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Social interactions accompany individuals throughout their whole lives. When examining the underlying mechanisms of social processes, dynamics of synchrony, coordination or attunement emerge between individuals at multiple levels. To identify the impactful publications that studied such mechanisms and establishing the trends that dynamically originated the available literature, the current study adopted a scientometric approach. A sample of 543 documents dated from 1971 to 2021 was derived from Scopus. Subsequently, a document co-citation analysis was conducted on 29,183 cited references to examine the patterns of co-citation among the documents. The resulting network consisted of 1,759 documents connected to each other by 5,011 links. Within the network, five major clusters were identified. The analysis of the content of the three major clusters—namely, “Behavioral synchrony,” “Towards bio-behavioral synchrony,” and “Neural attunement”—suggests an interest in studying attunement in social interactions at multiple levels of analysis, from behavioral to neural, by passing through the level of physiological coordination. Furthermore, although initial studies on synchrony focused mostly on parent-child interactions, new hyperscanning paradigms are allowing researchers to explore the role of biobehavioral synchrony in all social processes in a real-time and ecological fashion. Future potential pathways of research were also discussed.
... Finally, Davis and Kramer (2021) argue that lack of maternal response leads to distress for the infant. As evidence, they cite a blog post by Narvaez (2011) and a study by Middlemiss, Granger, Goldberg, and Nathans (2012), which investigated the synchrony in cortisol levels between the mothers and infants during an in-residence and hospital-based sleep training programme conducted with 25 motherinfant dyads who were referred to the sleep training programme. Middlemiss et al.'s (2012) findings actually revealed no significant increase in the cortisol levels of infants before and after the sleep training, rather without the infant's distress cue, mother's cortisol levels decreased. ...
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Davis and Kramer (2021) in their commentary on our study (Bilgin & Wolke, 2020) state that we 'argue that leaving an infant to "cry it out", rather than responding to the child's cries, had no adverse effects on mother-infant attachment at 18 months' (Davis & Kramer, 2021, p. 1). Instead, we wrote that 'contemporary practice by some parents to occasionally or often "leaving infant to cry it out" during the first 6 months was not associated with adverse behavioural development and attachment at 18 months' (p. 8). Based on the empirical findings of our observation study, we suggested that 'increased use of "leaving to cry it out" with age may indicate differential responding by mothers to aid the development of infant self-regulation' (p. 8). Indeed, in an editorial of our study, the joint editor of this journal concluded that 'Bilgin and Wolke responsibly conclude that there is little reason to make definitive pronouncements to parents of young infants about how much to let them cry it out, given that both the attachment theory (responding promptly early promotes security) and learning theory (ignoring crying prevents dependency) formulations were unsupported by their findings' (Zeanah, 2020, p. 1172).
... Additionally, we conducted a modified version on the TSST therefore it maybe the modification to the TSST that may have led to participants not mounting a stress response. Physiological attunement is a key indicator of relationship dynamics (e.g., supportive behaviors, relationship satisfaction, etc.; Ha et al., 2016;Middlemiss, Granger, Goldberg, & Nathans, 2012;Papp et al., 2013). However, the majority of studies have focused on the stress response system and family and romantic relationships. ...
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Friendships constitute important relationships, and often function to reduce stress, but have been under-studied. In mother-child dyads, infants coordinate their stress response with their caregivers without experiencing the stressor themselves. The current study used a modified version of the Trier Social Stress Test to examine whether i) friends are physiologically attuned (i.e., cortisol and progesterone); ii) attunement differs as a function of social acceptance or rejection external to the dyad; and, iii) friends can ‘catch’ a stress response only through non-verbal cues. Friends showed both cortisol and progesterone attunement at the beginning of the study. Friends showed cortisol attunement across time and conditions. Friends’ progesterone levels were significantly, but negatively associated across time and conditions. They did not, however, show a stress contagion as a result of one friend experiencing stress. These findings suggest that cortisol and progesterone play different roles in the attunement of stress and subsequent affiliation.
... As a first step, we conducted descriptive statistics and partial correlations between cortisol values for parents and infants across the three times of measurement (see Table 1). Examining within-time intercorrelations between parent and infant cortisol is one means used in previous research to assess attunement (Middlemiss et al., 2012;Thompson & Trevathan, 2008). Mothers' and infants' cortisol levels were significantly correlated at all three time points, as were fathers' and infants' cortisol, providing preliminary evidence for parent and infant cortisol attunement. ...
Article
Father‐infant and mother‐infant (one‐year‐olds) adrenocortical attunement was explored during the Strange Situation Procedure (SSP) among 125 father‐infant and 141 mother‐infant dyads. Cortisol was assessed at baseline (T1), 20 (T2), and 40 minutes (T3) after the first parent‐infant separation. Initial correlations indicated significant associations between father‐infant and mother‐infant cortisol at each time. Cortisol interdependence was further explored using Actor‐Partner Interdependence Models. There was no evidence supporting cortisol interdependence based on within‐time residual correlations between parent‐infant cortisol, once stability and cross‐lagged paths were controlled. Infant cortisol at T2 predicted T3 cortisol for fathers and mothers resulting in a series of follow‐up exploratory analyses to examine mediating processes which revealed that infant distress during the SSP predicted infant T2 cortisol, which, in turn, predicted infant negativity during the 15‐min mother‐infant teaching task that followed the SSP. Among father‐infant dyads, infant T2 cortisol predicted infant negativity during father‐infant interaction, with infants expressing more negativity having less sensitive fathers. Findings provide little support of parent‐infant adrenocortical attunement across either father‐infant or mother‐infant dyads during the SSP, but preliminary evidence indicates infant distress as a potential mediator. Future research may want to focus on affective and behavioral processes that underlie the concept of parent‐infant adrenocortical attunement.
... Research has shown that the practice may negatively impact children in a number of ways. A lack of maternal response to crying (a) may be associated with elevated infant cortisol (Middlemiss, Granger, Goldberg, & Nathans, 2012), which can have long-term effects on brain development and cognitive function; (b) causes issues with the development of self-regulation (social contact is necessary for self-regulation skills to develop); and (c) is negatively associated with independence and confidence throughout childhood (for a summary of these arguments, see Narvaez, 2011). Indeed, in a recent paper that serves as the focus of this commentary, the authors acknowledged that a lack of detrimental effects due to 'cry it out' found in their work was surprising in the context of both attachment theory and learning theory (Bilgin & Wolke, 2020a). ...
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In their recent paper published in JCPP, Bilgin and Wolke (2020a) argue that leaving an infant to ‘cry it out’, rather than responding to the child’s cries, had no adverse effects on mother–infant attachment at 18 months. This finding opposes evidence across a wide range of scientific fields. Here, we outline several concerns with the article and argue against some of the authors’ strong claims, which have already gained media attention, including a report on the NHS website. We suggest that the authors’ conclusions should be considered one piece of a larger scientific whole, where ‘cry it out’ seems, overall, to be of detriment to both attachment and development. Crucially, we are concerned that this study has issues regarding power and other analytical decisions. More generally, we fear that the authors have overstated their findings and we hope that members of the public do not alter their parenting behaviours in line with such claims without further research into this controversial topic.
... As a first step, we conducted descriptive statistics and partial correlations between cortisol values for parents and infants across the three times of measurement (see Table 1). Examining within-time intercorrelations between parent and infant cortisol is one means used in previous research to assess attunement (Middlemiss et al., 2012;Thompson & Trevathan, 2008). Mothers' and infants' cortisol levels were significantly correlated at all three time points, as were fathers' and infants' cortisol, providing preliminary evidence for parent and infant cortisol attunement. ...
... However, there is no empirical evidence that leaving infants to cry it out actually induces stress to the infant. The only study on the stress levels of infants after a 5-day intervention programme including leaving infants to cry it out gradually revealed no change in infant cortisol levels (Middlemiss, Granger, Goldberg, & Nathans, 2012). Short-and long-term chronic stress impacts humans differently (Monaghan & Haussmann, 2015), and early stress may increase adaptive strategies (Ellis & Del Giudice, 2019). ...
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Background: Leaving infant to cry it out has been the subject of discussion among researchers and parents. Nevertheless, there is paucity of empirical research investigating the association between leaving infant to cry it out and consequent crying duration and frequency, mother-infant attachment and behavioural development. Methods: The sample with complete longitudinal data comprised 178 infants and their caretakers. Parental use of 'leaving infant to cry out' and cry duration were assessed with maternal report at term, 3, 6 and 18 months, and frequency of crying was assessed at term, 3 and 18 months of age. Attachment was measured at 18 months using the strange situation procedure. Behavioural development of the infant was assessed with two observational measures and a parent-report questionnaire at 18 months. Results: The use of 'leaving infant to crying' was rare at term and increased over the next 18 months. 'Leaving infants to cry it out' at term was associated with a decrease in crying frequency at 3 months. Furthermore, leaving infants to cry it out a few times at term and often at 3 months was associated with shorter fuss/cry duration at 18 months of age. No adverse impacts of leaving infants to cry it out in the first 6 months on infant-mother attachment and behavioural development at 18 months were found. Conclusions: Contemporary practice of some parents in the United Kingdom to occasionally or often 'leaving infant to cry it out' during the first 6 months was not associated with adverse behavioural development and attachment at 18 months. Increased use of 'leaving to cry it out' with age may indicate differential responding by parents related to infant self-regulation.
... In behaviorally hypoaroused babies, affectdriven sensory-motor cues are partially extinguished, either due to biological propensity or early 'learned helplessness' or both, resulting in less parental engagement and shortened reciprocity chains. These infants may be particularly vulnerable to the developmental impacts of suboptimal environmental stimulation and disrupted parent-infant biobehavioral synchrony (Middlemiss et al., 2012). ...
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Autism spectrum disorders (ASD) are an emergent public health problem, placing significant burden upon the individual, family and health system. ASD are polygenetic spectrum disorders of neural connectome development, in which one or more feedback loops amplify small genetic, structural, or functional variations in the very early development of motor and sensory-motor pathways. These perturbations trigger a ‘butterfly effect’ of unpredictable cascades of structural and functional imbalances in the global neuronal workspace, resulting in atypical behaviors, social communication, and cognition long-term. The first 100 days post-term are critically neuroplastic and comprise an injury-sensitive developmental window, characterized by a neural biomarker, the persistence of the cortical subplate, and a behavioral biomarker, the crying diathesis. By the time potential diagnostic signs are identified, from 6 months of age, ASD neuropathy is already entrenched. The International Society for Autism Research Special Interest Group has called for pre-emptive intervention, based upon rigorous theoretical frames, and real world translation and evaluation. This paper responds to that call. It synthesizes heterogenous evidence concerning ASD etiologies from both psychosocial and biological research literatures with complexity science and evolutionary biology, to propose a theoretical framework for pre-emptive intervention. This paper hypothesizes that environmental factors resulting from a mismatch between environment of evolutionary adaptedness and culture initiate or perpetuate early motor and sensory-motor lesions, triggering a butterfly effect of multi-directional cascades of atypical developmental in the complex adaptive system of the parent and ASD-susceptible infant. Chronic sympathetic nervous system/hypothalamic-pituitary-adrenal axis hyperarousal and disrupted parent-infant biobehavioral synchrony are the key biologic and behavioral mechanisms perpetuating these atypical developmental cascades. A clinical translation of this evidence is proposed, for application antenatally and in the first 6 months of life, as pre-emptive intervention for ASD.
... Das Kind lernt, dass es mit seinem Schreien nichts bewirken kann und in einem hilflosen Zustand allein gelassen wird [6,10]. So zeigt beispielsweise die Studie von Middlemiss et al. [11], dass im Rahmen eines 5-tägigen Schlaftrainings die Stresslevel der schreienden Säuglinge und auch das Stresserleben der Mütter sehr hoch waren. Nach 3 Tagen hatten die Säuglinge zwar aufgehört zu schreien, ihre Stresslevel waren jedoch unverändert hoch -lediglich der Stress der Mütter ließ nach. ...
... • Medical organizations should advocate for social equity as a means to health but have missed opportunities to do so. remain high when infants are separated from their mothers at night, and maternal-infant cortisol asynchrony occurs (Middlemiss, Granger, Goldberg, & Nathans, 2012). ...
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Sudden unexpected infant death (SUID) and sudden infant death syndrome (SIDS) prevention has focused on modifying individual behavioural risk factors, especially bedsharing. Yet these deaths are most common among poor and marginalized people in wealthy countries, including U.S. Blacks, American Indians/Alaskan Natives, New Zealand Māori, Australian Aborigines, indigenous Canadians, and low‐income British people. The United States now has the world's highest prevalence of SUID/SIDS, where even Whites' SIDS prevalence now approaches that of the Māori. Using public databases and the literature, we examine SUID/SIDS prevalence and the following risk factors in selected world populations: maternal smoking, preterm birth, alcohol use, poor prenatal care, sleep position, bedsharing, and formula feeding. Our findings suggest that risk factors cluster in high‐prevalence populations, many are linked to poverty and discrimination and have independent effects on perinatal outcomes. Moreover, populations with the world's lowest rates of SUID/SIDS have low‐income inequality or high relative wealth, yet have high to moderate rates of bedsharing. Employing syndemics theory, we suggest that disproportionately high prevalence of SUID/SIDS is primarily the result of socially driven, co‐occurring epidemics that may act synergistically to amplify risk. SUID must be examined through the lens of structural inequity and the legacy of historical trauma. Emphasis on bedsharing may divert attention from risk reduction from structural interventions, breastfeeding, prenatal care, and tobacco cessation. Medical organizations play an important role in advocating for policies that address the root causes of infant mortality via poverty and discrimination interventions, tobacco control, and culturally appropriate support to families.
... Breastsleeping, a term coined by James McKenna, refers to the sleeping-feeding interactions of breastfeeding mothers and infants at night and presumes a shared sleep surface. Throughout the article, for clarity, I will refer to all of these practices under the heading of ' co-sleeping' in that they are all framed as alternatives to sleep-training, involve parental responsiveness to infants at night, and do not involved early independence training. of attachment also supports many of the claims made by co-sleeping advocates, who are able to cite studies indicating that infants left alone have elevated stress hormones even after they learn not to cry (Middlemiss, Granger, & Nathans 2012) and that over time, that this may impair brain development (Bartick et al. 2017) as a result of 'toxic stress' (Shonkoff et al. 2012). Sleep training practices are based on theories of behaviour modification (Hiscock & Fisher 2015). ...
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This article proposes to investigate maternal practices concerning infant sleep from a feminist perspective, with particular attention to the growing critical interest in vulnerability. The topic of baby sleep and the practices that should be employed to manage it is one of the most controversial topics of paediatric research and parenting advice. It is also an issue that causes division between mothers. Opinion is polarised into two camps, one recommending independent sleep achieved through practices of sleep-training that involve leaving babies to cry; the other that encourages practices of ‘co-sleeping’ and attentive and responsive night-time care often achieved through mother and baby sharing a bed. In this article, I argue that both advocates of sleep-training and co-sleeping are seeking to offer neoliberally-informed individual solutions to social and political problems. I argue that baby sleep and the maternal practices employed to manage it have to be understood as strategies for managing human vulnerability in a culture and political environment that seeks to ignore it. I suggest that the debate between sleep-training and co-sleeping can be better understood through a consideration of care relations and the care deficit in post-industrial society. I argue that attention also needs to be given to discourses of medicalised childcare, and how the subject positions of mothers and babies are deeply troubled in a society where subjectivity is equated with independence.
... Sleep training involves parents leaving an infant or child alone in a separate room at night, and limiting responsiveness to its cries to the point of extinction, thus encouraging it to self-settle [43]. These practices are arguably disturbing for the infant or child, who is responding to the separation from its caregiver, and the cries are stressful for parents [44]. Although very popular and widely recommended [45], sleep training is counterintuitive to attachment theory and other evolutionary tenets of a responsive parent-offspring relationship. ...
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Night terrors, also known as sleep terrors, are an early childhood parasomnia characterized by screams or cries, behavioral manifestations of extreme fear, difficulty waking and inconsolability upon awakening. The mechanism causing night terrors is unknown, and a consistently successful treatment has yet to be documented. Here, we argue that cultural practices have moved us away from an ultimate solution: cosleeping. Cosleeping is the norm for closely related primates and for humans in non-Western cultures. In recent years, however, cosleeping has been discouraged by the Western medical community. From an evolutionary perspective, cosleeping provides health and safety benefits for developing children. We discuss night terrors, and immediate and long-term health features, with respect to cosleeping, room-sharing and solitary sleeping. We suggest that cosleeping with children (≥1-year-old) may prevent night terrors and that, under certain circumstances, cosleeping with infants (≤11-months-old) is preferable to room-sharing, and both are preferable to solitary sleeping.
... Participants can consciously change their behavioral response to a stressor event, but this does not necessarily indicate a similar change in their physiological experience of stress. This dissociation between physiological and behavioral markers of stress was evidenced as early as 4 to 6 months of age (Middlemiss, Granger, Goldberg, & Nathans, 2012). Thus, in this research, the measure of both behavioral (as indicated in the questionnaire data) and physiological (as indicated in the measure of cortisol and heart rate variability) provided a clearer indication of participants' experiences of stressor events and the impact of the intervention for both stressor response and recovery. ...
Thesis
Considerable psycho-physiological research on empathy examines biological structures such as the hypothalamic-pituitary-adrenal axis (HPA-axis) and oxytocin systems as efficacious methods for strengthening positive emotional responses. This study recruited 76 adult participants (54 female, 23 male) for the purpose of evaluating the effects oxytocin and fiction reading have on empathetic responses. Participants completed a measure of trauma and received either intranasal oxytocin, a story created to induce emotional responses, or a neutral non-fiction story. Results supported existing research stating that heart rate variability (HRV) is a more sensitive measure of stress. HRV statistically significantly interacted between type of stressor and PTSD symptomology Fa×b (1, 70) = 5.018, p = .028, η2 =0.06. Scores on the Interpersonal Reactivity Index (IRI) indicated there were increases in empathy across time, but were not impacted by exposure to stress or treatment condition. Trauma was identified as a statistically significant factor on heart rate variability F(1, 70) = 8.39, p = .005, η2 = .10. Treatment condition did not impact cortisol levels across time F(2, 71) = .2.532, p = .087, η2 = .11. Taken together, these results suggest support for the use of biomarkers in measuring the rate of stress and recovery for those with and without trauma. These findings suggest potential avenues for translational research and implications for theory and practice.
... However, after a few nights of separation for sleep, the infant cortisol levels remained high, indicating physiologic stress, even though they no were no longer crying and appeared to "self-settle." In contrast, the mothers' cortisol levels decreased and were no longer correlated with those of their infants, reflecting that they were unaware of their infants' stress and were out of sync with them (Middlemiss, Granger, Goldberg, & Nathans, 2012). Prolonged childhood stress can create long-term changes in brain architecture and behaviours that could even be passed on to the next generation, in a phenomenon known as "toxic stress" (Shonkoff et al., 2012). ...
... As reviewed, specific hypotheses regarding which GxE model would emerge could not be made a priori due to the dearth of research differentiating the different models with statistical rigor and the variety of confounding variables that may impact the manifestation of the models (Del Giudice, 2016). Given that mothers consistently show declines in cortisol secretion (following anticipatory anxiety) throughout both potent and mild infant stress paradigms (Atkinson et al., 2013;Davis & Granger, 2009;Hibel, Granger, Blair, & Cox, 2009;Laurent, Ablow, & Measelle, 2011;Middlemiss, Granger, Goldberg, & Nathans, 2012;Sethre-Hofstad, Stansbury, & Rice, 2002;van Bakel & Riksen-Walraven, 2008), lower baseline cortisol levels (i.e., intercepts in our statistical model) and/or buffered cortisol reactivity (i.e., slopes in our statistical model) to the current mother-infant separation stressor were considered to be ideal maternal cortisol patterns in this study. ...
Article
A mother's cortisol secretion is importantly associated with her own mental health and her infant's cortisol secretion. This study investigated the influences of maternal history of care and maternal DRD2, SLC6A3, and OXTR genotypes on maternal cortisol in the context of infant stress. A community sample of 296 mother-infant dyads completed a maternal separation at infant age 17 months. Maternal salivary cortisol, buccal cells, and self-reported history of care were collected. Multilevel models revealed that history of care had a greater influence on maternal baseline cortisol (but not cortisol trajectory) for mothers with more plasticity alleles of SLC6A3 (10R) and OXTR (G), relative to mothers with fewer or no plasticity alleles. Findings indicate that a mother's history of care is related to her cortisol secretion in anticipation of infant stress, but that this relation depends on her genetic characteristics. Findings are discussed in relation to the maternal protective system and anticipatory cortisol secretion.
... Parent-child adrenocortical attunement, or the coordination of hypothalamicpituitary-adrenal (HPA) axis activity between individuals, is one aspect of a bidirectional system that facilitates child learning of their social environment (Hibel et al. 2015). Maternal and child cortisol levels are Battuned^or Bcoregulated^at across the day and at multiple points in development (Granger et al. 1998;Hibel et al. 2014;Laurent et al. 2012;Middlemiss et al. 2012;Ruttle et al. 2011). Research examining physiological attunement between the child and their parents has largely been conducted in animal models, and has only recently been conducted in human models (Sethre-Hofstad et al. 2002). ...
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Physiological attunement between mothers and infants is emerging as an important indicator of infant information processing, emotion regulation, and health outcomes. Far less understood is the role of paternal support and maternal satisfaction with her partner in facilitating the mother-infant biorhythm. This exploratory study evaluated the impact of maternal satisfaction with her romantic partner and mother-infant communication features on mother-infant hypothalamic-pituitary-adrenal (HPA) axis attunement. Mothers were asked to complete a series of questionnaires in the presence of her infant, requiring approximately 45 min, occupying maternal attention and serving as a mild challenge for the infant. After completion of the questionnaires, mothers’ and infants’ saliva were collected and later assayed for cortisol. Maternal reports of couple satisfaction (n = 33) impacted mother-infant adrenocortical attunement such that those reporting more satisfaction with their partner showed more attunement with their infants. Maternal reports of couple satisfaction (n = 33) were associated with lower infant, but not lower maternal cortisol levels. Finally, mothers who reported engaging in more infant-directed speech (n = 47), a potential index of maternal sensitivity, showed more attunement with their infants. Removal of an outlier (infant cortisol) reduced the findings to marginal significance in the predicted direction. Though this study is exploratory and the findings are tentative, we conclude that one way that fathers may indirectly contribute to infant outcomes is through social support of the mother, and that infant-directed speech may facilitate mother-infant attunement.
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Introduction In Western cultures, parents often view infant sleep as problematic. Family, friends, and doctors may advise parents to “sleep train” assuming it is safe and effective, without considering its possible side effects, including its impact on breastfeeding. Unfortunately, it may reduce night feeds and result in earlier supplementation or weaning. The larger question is whether sleep training is worth the risk (i.e., does it improve infant sleep?). Our goal was to examine the data on the effectiveness of sleep training interventions on infant/toddler sleep. Methods PubMed and Google Scholar were searched for specific terms to identify articles that included behavioral sleep interventions and objective measures of sleep pre-and postntervention. Two objective infant sleep measures were examined: Night wakings and total sleep duration. Articles were then reviewed for evidence of the effectiveness of these interventions to reduce night wakings and increase total sleep duration. Results Five articles were identified that met the criteria for inclusion. Overall, there was no evidence that sleep training improves infant sleep. Applications for Practice The claim that sleep training is effective in changing infant sleep is not warranted. Given the potential side effects on breastfeeding, parents should be cautioned about engaging these behavioral sleep interventions if they have breastfeeding goals they want to achieve.
Article
Human infants spend most of their time sleeping, but over the first few years of life their sleep becomes regulated to coincide more closely with adult sleep (Galland et al., 2012; Paavonen et al., 2020). Evidence shows that co-sleeping played a role in the evolution of infant sleep regulation, as it is part of an ancient behavioral complex representing the biopsychosocial microenvironment in which human infants co-evolved with their mothers through millions of years of human history (Ball, 2003; McKenna 1986, 1990). This paper is a conceptual, interdisciplinary, integration of the literature on mother-infant co-sleeping and other mother-infant co-regulatory processes from an evolutionary (biological) perspective, using complexity science. Viewing the mother-infant dyad as a “complex adaptive system” (CAS) shows how the CAS fits assumptions of regulatory processes and reveals the role of the CAS in the ontogeny of mother-infant co-regulation of physiological (thermoregulation, breathing, circadian rhythm coordination, nighttime synchrony, and heart rate variability) and socioemotional (attachment and cortisol activity) development.
Article
Bedsharing is controversial for nighttime caregiving in the U.S. today, as in most of the West. However, from the standpoint of evolutionary pediatrics, anthropology, and cultural psychology, bedsharing is not controversial at all, representing the context for human infant evolution and conferring a host of physiological benefits to the infant as well as the mother. In an effort to understand the rise in Western bedsharing in recent decades (and following Ball, 2002; McKenna & Volpe, 2007), Salm Ward (2015) systematically reviewed the literature on mother-infant bedsharing and identified ten reasons why mothers choose to bedshare: (1) breastfeeding, (2) comforting for mother or infant, (3) better/more sleep for infant or parent, (4) monitoring, (5) bonding/ attachment, (6) environmental reasons, (7) crying, (8) cultural or familial traditions, (9) disagree with danger, and (10) maternal instinct. The current paper offers the “review behind the review,” highlighting the scientific evidence behind the reasons mothers give for their decision to bedshare, focusing on how mothers’ decisions about infant sleep location influence infant behavior and development.
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Infants evolved in the context of close contact (including co-sleeping). Evolutionary context is rarely considered in psychological infant sleep research, and Western sleep researchers make assumptions about what optimal “normal” infant sleep is and how to achieve early, deep, infant sleep consolidation and avoid infant sleep problems. However, an evolutionary and anthropological view of infant sleep as species-typical recognizes that human evolution likely prepared the infant brain for optimal development within its evolutionary context – co-sleeping. Thus, “normal” infant sleep, sleep consolidation, and sleep problems should all be understood within the framework of co-sleeping infants, not the historically new-phenomenon of solitary-sleeping infants. Much work needs to be done in order to understand “normal” infant sleep as species-typical and how adaptive infants are to environments that stray from their evolutionary norm.
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Extensive research has established a positive association between caregiver-child behavioral synchrony and child developmental functioning. Burgeoning research examining physiological synchrony has yet to elucidate its impact for children’s developing self-regulation. The objectives of this systematic review were to: 1) determine whether there is evidence that caregiver-child physiological synchrony promotes positive child development, 2) examine developmental differences in physiological synchrony and its correlates, and 3) explore whether context, risk, and/or stress influence patterns of synchrony. Sixty-nine studies met the following criteria on PubMed and PsycINFO: 1) peer-reviewed empirical articles in English that 2) examine autonomic, hypothalamic-pituitary-adrenocortical, and/or central nervous system activity 3) for caregivers and children 4) in response to a task and 5) directly examine the association between caregiver and child physiology. Findings varied based on developmental period and current behavioral context. Functional differences may exist across physiological systems and contexts. Synchrony may have different developmental consequences for dyads with and without certain risk factors. Few studies examine physiological synchrony across multiple systems or contexts, nor do they measure child characteristics associated with synchrony. Statistical and methodological challenges impede interpretation. Findings generally support the idea that physiological synchrony may support children’s developing self-regulation. Longitudinal research is needed to examine child developmental outcomes over time.
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Objective: To describe the changes in temporal characteristics of sleep-wake cycle, which can serve as non-motor manifestations of an early stage of Parkinson's disease (PD), using the model of preclinical PD in rats of two age groups. Material and methods: A prolonged (up to 21 days) model of preclinical PD in middle-aged (7-8 month) and aged (19-20 month) rats was created. The model was based on cumulative inhibition of proteasomal system of the brain caused by intranasal administration of lactacystin, a specific proteasome inhibitor. Polysomnographic data were recorded daily using telemetric Dataquest A.R.T. System (DSI, USA) in unrestrained animals. Results and conclusion: Aging was accompanied with increased sleepiness during the active (dark) phase of the day (as was implied by a two-fold increase in the total time of drowsiness) and with 1.5-fold growth of light sleep during the inactive phase of the day. A common feature of sleep disturbances in the model of preclinical PD in both middle-aged and aged rats was hypersomnia during the active phase of the day. It was suggested to be similar to the excessive daytime sleepiness in humans. Hypersomnolence was more pronounced in aged rats because it added to sleepiness developing with aging. In both age groups, the model of preclinical PD was also associated with a decrease in EEG delta power during slow-wave sleep. It is considered dangerous because it might represent the decrease in protein synthesis rate and the weakening of restorative processes in neurons, occurring with the prolonged inhibition of proteasomal system of the brain. Sleep disturbances, identified the model of preclinical PD in rats of different age, may be recommended for clinical validation as low-cost early signs indicating the initial stage of PD.
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Behavioral insomnia is the most common sleep disorder in young children. It significantly reduces the quality of parent's life and is one of the common complaints to a pediatrician or neurologist. The basis treatment of childhood insomnia is behavioral therapy, which includes sleep hygiene, age-appropriate daily routine and sleep associations, stable bedtime routines, positive reinforcement, bedtime fading, scheduled awakenings. Although a systematic ignoring («crying it out») is effective and widely used in behavioral therapy, it has low compliance and its safety is insufficiently studied. Therefore, a systematic ignoring is not a priority method of behavioral therapy and should not be used in children under 6 months of age. Behavioral therapy of childhood insomnia is complemented by psychological and informational support from parents, and in some cases, drug therapy. Prevention includes education of expectant parents on baby sleep hygiene.
Article
The human need for sleep is universal and unquestioned; however, humans vary in their sleep needs according to age, individual differences, as well as cultural and social norms and practices. Therefore, what is “normal” in infant sleep and the development of sleep architecture in humans is highly dependent on biological and sociocultural variables as well as socially constructed assumptions about what infant sleep “should” look like. This paper uses a multidisciplinary approach to review papers from fields including pediatrics, anthropology, psychology, medicine, and sociology to understand “normal” infant sleep. Because human culture and behavioral practice changes much more quickly than evolved human biology, and because human evolutionary history occurred in the context of breastfeeding and cosleeping, new work in the field of infant sleep architecture development would benefit from a multidisciplinary approach. To come to a consensus about what is “normal” infant sleep, researchers must agree on underlying basic assumptions of infant sleep from which to ask question and interpret findings.
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Although most people want children to thrive, many adults in industrialized nations have forgotten what that means and how to foster thriving. We review the nature and effects of the evolved developmental system for human offspring, a partnership system that fosters every kind of wellbeing. The environment and the type of care received, particularly in early life, shape neurobiological process that give rise to social and moral capacities. A deep view of history sheds light on converging evidence from the fields of neuroscience, developmental psychology, epigenetics, and ethnographic research that depicts how sociomoral capacities are not hardwired but are biosocially constructed. The Evolved Nest is the ecological system of care that potentiates both physical and psychological thriving, the foundations of cooperative and egalitarian societies. Deprivation of the evolved nest thwarts human development, resulting in sub-optimal, species-atypical outcomes of illbeing, high stress reactivity, dysregulation, and limited sociomoral capabilities. Utilizing a wider lens that incorporates humanity’s deep ancestral history, it becomes clear that deprivation of the evolved nest cuts against the development of human nature and humanity’s cultural heritage. Returning to providing the evolved nest to families and communities holds the potential to revise contemporary understandings of wellbeing and human nature. It can expand current metrics of wellness, beyond resilience to optimization.
Article
Co-sleeping is a complex familial phenomenon that has yet to be well understood by Western scientists. This paper provides an interdisciplinary review of research from anthropology, nursing, pediatrics, sociology, social work, public health, family studies, and psychology to focus on the role of physical touch in the context of co-sleeping, and how close physical contact in this context affects infants and their caregivers. Including an anthropological, evolutionary view of co-sleeping with other perspectives highlights it as an experience-expectant proximal context for infant growth and development. From this view, the importance of physical contact and touch in the nighttime caretaking microenvironment of co-sleeping becomes a central question, rather than an artifactual byproduct of "unhealthy" sleep arrangements. Rather than trying to eliminate co-sleeping, public health messages for parents would likely benefit from a more culturally-sensitive approach that focuses on advising how to co-sleep safely for families choosing it. For families trying to retain physical closeness between parent(s) and infants in the context of modern (especially Western) infant care practices that have reduced this physical contact, co-sleeping can be an important developmental context for encouraging and engaging in sensitive and responsive caregiving and providing a context for maternal-infant physiological synchrony and regulation.
Chapter
Following their infant’s birth, parents in many societies in the global North experience acute sleep disruption for which few are adequately prepared, and which may result in profound and enduring negative outcomes such as parental depression and anxiety. For some babies, their parent’s inability to cope with sleep disruption results in harmful short-term outcomes (such as infants being medicalised, medicated, and abused); long-term consequences are more difficult to identify and therefore are understudied. Yet other parents, and indeed whole nations of parents, seem resilient to infant-related sleep disruption and take it all in their stride—so what differs? This chapter considers parental perceptions and experiences of night-time infant care and the strategies that are promoted and used for coping with infant-related sleep disruption. The potential consequences of these for parents, their babies, and society in general will be explored with suggestions for future research to fill current evidence gaps.
Article
Understanding maternal mental health and cortisol regulation across pregnancy and the relationship to the development of the offspring’s stress regulation is critical to a range of health outcomes. The aim of this study was to investigate infant and maternal cortisol in women with depression. Data were obtained from 241 pregnant women within Mercy Pregnancy and Emotional Wellbeing Study (MPEWS), a selected pregnancy cohort study. Depression was measured using the Structured Clinical Interview for DSM-IV (SCID-IV) and repeat Edinburgh Postnatal Depression Scale (EPDS). Repeated measures of antidepressant use, stressful events, anxiety symptoms and maternal hair cortisol concentrations (HCC) and infant cortisol at 12 months postpartum in saliva and hair. Socio-emotional outcomes were measured at 12 months by maternal report on the Brief Infant and Toddler Socio-emotional Assessment (BITSEA). This study found that maternal depression was not associated with maternal HCC. Anxiety, stress and antidepressant use were not associated with maternal HCC. Independently higher maternal 3rd trimester maternal depressive and anxiety symptoms were associated with lower infant cortisol response at 12 months of age. A higher number of postpartum stressful events was associated with lower infant cortisol response. Lower infant stress reactivity was associated with higher externalizing symptoms at 12 months of age. Future studies are required to understand implications for later mental health. Keywords: Depression, Antidepressants, Pregnancy, Cortisol, Hair, Child Mental Health
Chapter
During the developmental period of 6–12 months, infants deepen and solidify their developing relationships. By 6 or 7 months of age, attachments to and preference for primary caregivers are observable. Infants also begin to exhibit fear of strangers and actively seek proximity to attachment figures during this time. Chapter 4 presents research on typical and atypical social and emotional development for infants between the ages of 6 months and 12 months. It discusses how infants’ new capacity for mobility impacts social and emotional development, particularly in the areas of joint attention, social referencing, stranger anxiety, and understanding of the minds of others. The biobehavioral context of development at this age is discussed as well as caregiver practices that promote healthy social and emotional growth during this time period.
Article
In the current study, we examined the attunement and transmission of mother–child diurnal cortisol among maltreating (N = 165) and nonmaltreating (N = 83) mothers and their preschool-aged children. Over half of the families had a substantiated child maltreatment case with the mother as the perpetrator. Mothers collected three saliva samples (waking, midday, and bedtime) on themselves and their child on two consecutive days, which were later assayed for cortisol. This design allows for the examination of concurrent attunement, as well as cross-lagged transmission, across the day. Results from actor–partner interdependence models revealed significant differences in mother–child cortisol attunement and transmission between the maltreating and nonmaltreating groups. Specifically, only maltreating mothers transmitted cortisol to their children and were attuned at first waking; only nonmaltreating dyads were attuned at midday. Implications of these results for sociocultural models of stress physiology and for our understanding of how child maltreatment affects diurnal cortisol regulation are discussed.
Chapter
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Humanity’s evolutionary inheritances include many things beyond genes, such as self-organization and a developmental system for raising the young (evolved developmental niche or evolved nest). We present an evolutionary understanding of human species-typical and atypical development and need provision, as well as adult outcomes in species-typical contexts. Maslow noted that thwarting of basic needs fulfillment in early life has effects over the long term but he did not describe what a positive experience in early life looks like. We provide an evolutionary picture here. We describe the development of a retrospective basic needs fulfillment measure based on the Basic Needs Satisfaction Survey whose validation was described in Chapter 2. We tested the usefulness of basic needs history against an existing measure of evolved developmental niche history which were highly correlated in two studies. Hierarchical regression indicated that the measure Basic Needs History explained more of the variance than Evolved Developmental Niche History.
Article
Employing an experimental design, mother-to-infant transmission of stress was examined. Mothers (N = 117) were randomized to either have a positive or conflictual discussion with their marital partners, after which infants (age = 6 months) participated in a fear and frustration task. Saliva samples were collected to assess maternal cortisol responses to the discussion and infant cortisol responses to the challenge task. Results indicate maternal cortisol reactivity and recovery to the conflict (but not positive) discussion predicted infant cortisol reactivity to the infant challenge. Mothers’ positive affect during the discussion buffered, and intrusion during the free-play potentiated, mother-to-infant adrenocortical transmission. These findings advance our understanding of the social and contextual regulation of adrenocortical activity in early childhood.
Article
Many parents cite lack of sleep as the single hardest aspect of becoming a parent (Mindell et al, 2009). Chronic sleep deprivation has numerous well-known physical, emotional and psychological effects on children and adults (Orzel-Gryglewska, 2010). Parents who are seeking support for their child's sleep may turn to social media, the internet or popular parenting literature for strategies to deal with disrupted or shortened duration of sleep, and may be unaware of the potential negative consequences this could have on their child's psychological, emotional, and physical wellbeing in the short, medium and long term. Health professionals working with families with young children need to be educated and well-informed about the range of strategies available to parents, and to be able to support them to choose options that are protective of infant and maternal mental health and wellbeing.
Book
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Research guided by attachment theory as formulated by Bowlby and Ainsworth is branching out in exciting new directions. The 12 chapters collected together in this Monograph present theoretical and methodological tools that will facilitate further research on attachment across the life span, across generations, and across cultures. The Monograph is divided into 4 parts. Part 1 provides the theoretical framework, emphasizing the ethological and the psychoanalytic roots of attachment theory. Part 2 is concerned with translating theory into measurement (presenting the Attachment Q-sort and the Adult Attachment Interview that raised attachment research to the level of representation). Part 3 chapters examine short-term and long-term adaptations to nonmaternal care. Part 4 is devoted to cross-national research on attachment in infancy (Germany, Japan, and Israel).
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In this study, the authors examined parent-adolescent cortisol associations in 45 families with adolescent children (24 girls; M age = 15.78 years, SD = 1.44 years). Family members' salivary cortisol levels were measured seven times a day on 2 typical weekdays. Family members provided reports of demographic and health variables, and adolescents rated parent-child relationship characteristics. After accounting for the effects of time of day and relevant demographic and health control variables on cortisol levels, hierarchical linear models indicated the presence of significant covariation over time in mother-adolescent cortisol (i.e., physiological synchrony). Furthermore, moderating tests revealed that mother-adolescent cortisol synchrony was strengthened among dyads characterized by mothers and adolescents spending more time together, and in families rated higher on levels of parent-youth shared activities and parental monitoring or supervision. Analysis of momentary characteristics indicated that maternal presence at the time of cortisol sampling lowered adolescent cortisol levels but did not account for mother-adolescent cortisol synchrony. Within-family physiological synchrony was amplified in momentary contexts of elevated maternal negative affect and elevated adolescent negative affect.
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The importance of understanding which environmental and biological factors are involved in determining individual differences in physiological response to stress is widely recognized, given the impact that stress has on physical and mental health. The child-mother attachment relationship and some genetic polymorphisms (5-HTTLPR, COMT and GABRA6) were tested as predictors of salivary cortisol and alpha amylase concentrations, two biomarkers of hypothalamic-pituitary-adrenocortical (HPA) axis and sympathetic adrenomedullary (SAM) system activity, during the Strange Situation (SS) procedure in a sample of more than 100 healthy infants, aged 12 to 18 months. Individual differences in alpha amylase response to separation were predicted by security of attachment in interaction with 5-HTTLPR and GABRA6 genetic polymorphisms, whereas alpha amylase basal levels were predicted by COMT x attachment interaction. No significant effect of attachment, genetics and their interaction on cortisol activity emerged. These results help to disentangle the role played by both genetic and environmental factors in determining individual differences in stress response in infancy. The results also shed light on the suggestion that HPA and SAM systems are likely to have different characteristic responses to stress.
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Attachment research has shown the emergence of individual differences in the security of infant-mother attachment during the first year of life as well as their importance for later social-emotional development. A biobehavioral perspective may help settle disagreements about the validity and interpretation of 12-month-old infants' different behavioral patterns of attachment assessed by Ainsworth's Strange Situation. It was shown that, despite less overt distress in insecure-avoidant infants after short separations from the mother, overall cardiac measures indicate arousal patterns similar to the secure infants during separation. However, differences in cardiac response emerged with regard to object versus person orientation during reunion. Additionally, findings of increased cortisol in both insecure-avoidant and disorganized infants support the theoretical interpretation that these infants, in contrast to secure infants, lack an appropriate coping strategy.
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The role of the mother-toddler attachment relationship in moderating the relations between behavioral inhibition and changes in salivary cortisol levels in response to novel events was examined in 77 18-month-olds. Behavioral inhibition was determined by observing toddler inhibition of approach to several novel events. Attachment security to mother was assessed using the Ainsworth Strange Situation. Changes in salivary cortisol were used to index activity of the stress-sensitive hypothalamic-pituitary-adrenocortical (HPA) system. In addition, toddler coping behaviors and the behaviors used by mothers to help toddlers manage novel events were examined. Elevations in cortisol were found only for inhibited toddlers in insecure attachment relationships. Mothers in these relationships appeared to interfere with their toddlers' coping efforts. These results are discussed in the context of a coping model of the relations between temperament and stress reactivity.
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Cortisol has a pivotal role in physical and mental health, but relatively few studies have paid attention to individual differences in cortisol levels and the etiology of these differences, in particular their possible genetic basis. In this article we review the existing literature on the heritability of cortisol levels. Most of the studies, which have been carried out in genetically informative samples, lack methodological consistency with regard to frequency and timing of sample collection. The circadian rhythm in cortisol levels was often not taken into account. A power analysis shows that none of these studies used adequate sample sizes to distinguish genetic from shared environmental influences as a cause for familial aggregation. Results of a simultaneous analysis of 5 comparable twin studies suggest a heritability of 62%. Hence, we conclude that, to understand the contribution of genetic and (shared) environmental influences to variation in basal cortisol levels, future studies should be designed more rigorously with strict collection and sampling protocols, sufficient sample size and repeated measures across multiple days.
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Bedtime problems and frequent night wakings are highly prevalent in infants, toddlers, and preschoolers. Evidence suggests that sleep disruption and/or insufficient sleep have potential deleterious effects on children's cognitive development, regulation of affect, attention, health outcomes, and overall quality of life, as well as secondary effects on parental and family functioning. Furthermore, longitudinal studies have demonstrated that sleep problems first presenting in infancy may become chronic, persisting into the preschool and school-aged years. A solid body of literature now exists supporting the use of empirically-based behavioral management strategies to treat bedtime problems and night wakings in infants, toddlers, and preschoolers. The following practice parameters present recommendations for the use of behavioral (i.e., non-pharmacological) treatments of bedtime problems and night wakings in young children (aged 0 - 4. years 11 months). A companion review paper on which the recommendations are based was prepared by a taskforce appointed by the Standards of Practice Committee (SPC) of the American Academy of Sleep Medicine (AASM), and summarizes the peer-reviewed scientific literature on this topic. The authors of the review paper evaluated the evidence presented by the reviewed studies according to modified Sackett criteria. Using this information and a grading system described by Eddy (i.e., standard, guideline or option), the Standards of Practice Committee and Board of Directors of the American Academy of Sleep Medicine determined levels of treatment recommendation presented in the practice parameters below. These practice parameters provide 3 types of recommendations. First, recommendations are provided indicating that behavioral interventions are effective in the treatment of bedtime problems and night wakings in young children, producing reliable and significant clinical improvement in sleep parameters. Second, recommendations are made regarding specific behavioral therapies, including: (1) unmodified extinction, extinction with parental presence, and preventive parent education are all rated as individually effective therapies in the treatment of bedtime problems and night wakings (Standards), and (2) graduated extinction, bedtime fading/positive routines and scheduled awakenings are rated as individually effective therapies in the treatment of bedtime problems and night wakings but with less certainty (Guidelines). There was insufficient evidence to recommend standardized bedtime routines and positive reinforcement as single therapies. In addition, although behavioral therapies for bedtime problems and night wakings are often combined, there was insufficient evidence available to recommend one individual therapy over another or to recommend an individual therapy over a combination of therapies. Finally, recommendations are provided regarding the beneficial effects of behavioral treatments on secondary outcomes, including daytime functioning (child) and parental well-being.
Article
The article defines and assesses individual differences in attachment relationships, by referring to Q-methodology and the organization of behavior in infancy and early childhood. Evidence that infants who are secure with one parent are not necessarily secure with the other is particularly decisive on the distinction between attachment and temperament. Reports on attachment behavior outside the 12- 18 month age range have also been few and far between. Questions about what is learned during the formation of attachment relationships about the course of attachment after infancy and about individual differences beyond security and anxiety have received little attention.
Article
Synchrony—a construct used across multiple fields to denote the temporal relationship between events—has been applied to the study of mother–infant interaction and is suggested here as a framework for the study of interpersonal relationships. Defined as the temporal coordination of micro-level social behavior, parent–infant synchrony is charted in its development across infancy from the initial consolidation of biological rhythms during pregnancy to the emergence of symbolic exchange between parent and child. Synchrony is shown to depend on physiological mechanisms supporting bond formation in mammals—particularly physiological oscillators and neuroendocrine systems such as those involving the hormone oxytocin. Developmental outcomes of the synchrony experience are observed in the domains of self-regulation, symbol use, and the capacity for empathy across childhood and adolescence. Specific disruptions to the parameters of synchrony that may be observed in various pathological conditions, such as prematurity or maternal affective disorder, are detailed. A time-based, micro-analytic behavioral approach to the study of human relationship may offer new insights on intersubjectivity across the lifespan.
Article
Mother-infant separation from the maternal perspective is the focus of 2 studies reported here. First, a questionnaire, the Maternal Separation Anxiety Scale (MSAS), was developed and administered to 620 mothers soon after their infants were born and again 3 months later. The scale was highly reliable; factor analytic studies supported a 3-factor solution that served as the basis for forming 3 subscales labeled (1) Maternal Separation Anxiety, (2) Perception of Separation Effects on the Child, and (3) Employment-related Separation Concerns. In Study 2, maternal separation anxiety was assessed using the MSAS and other methods: an interview, an emotional status index (taken at the point of actual separation), and an observational index based on mothers' behavior during departure and reunion from their infants in a structured laboratory setting. Data from this multiple-measures approach supported the validity of the MSAS and verified the strength of the construct.
Article
The purpose of the current study was to investigate the development of sleep–wake and melatonin diurnal rhythms over the first 3 months of life, and the potential effect of bed-sharing on their development. It was hypothesized that increased maternal contact through bed-sharing would affect the development of rhythms in human infants. Ten solitary-sleeping and 8 bed-sharing infants' sleep–wake patterns and melatonin secretion were examined for 72 h at 1 and 3 months of age in their homes. Infants wore actigraphs on their ankles to study sleep–wake patterns. 6-Sulphatoxymelatonin was obtained through urine extracted from each diaper used over the 72-h study period. No significant differences were apparent in the timing of appearance or magnitude of sleep–wake or melatonin rhythms between bed-sharing and solitary-sleeping infants. Sleep–wake results were in the expected direction, with bed-sharing infants displaying more robust rhythms. A large degree of individual variability was evident in both rhythms, especially at 1 month. Three infants' parents regularly used a bright light source at night for feedings and diaper changes; the rhythms of these infants were less robust than the rest of the sample. Trends were mostly in the hypothesized direction and deserve attempts at replication with a larger sample. Copyright © 2007 John Wiley & Sons, Ltd.
Article
This study investigated the relationship between sleep arrangements and claims regarding possible problems and benefits related to co-sleeping. Participants were 83 mothers of preschool-aged children. Data were collected through parent questionnaires. Early co-sleepers (who began co-sleeping in infancy), reactive co-sleepers (children who began co-sleeping at or after age one), and solitary sleepers were compared on the dimensions of maternal attitudes toward sleep arrangements; night wakings and bedtime struggles; children's self-reliance and independence in social and sleep-related behaviours; and maternal autonomy support. The hypothesis that co-sleeping would interfere with children's independence was partially supported: solitary sleepers fell asleep alone, slept through the night, and weaned earlier than the co-sleepers. However, early co-sleeping children were more self-reliant (e.g. ability to dress oneself) and exhibited more social independence (e.g. make friends by oneself). Mothers of early co-sleeping children were least favourable toward solitary sleep arrangements and most supportive of their child's autonomy, as compared to mothers in other sleep groups. Reactive co-sleepers emerged as a distinct co-sleeping sub-type, with parents reporting frequent night wakings and, contrary to early co-sleepers, experiencing these night wakings as highly disruptive. Implications for parents and pediatricians are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Article
Salivary cortisol levels were assessed in 19-month-old infants following the Ainsworth Strange Situation procedure. 38 infants participating in Project Steep at the University of Minnesota served as subjects. Project Steep is a longitudinal intervention program designed to promote healthy parent-child relationships and to prevent emotional problems among children born to mothers who are at high risk for parenting problems. Following the Strange Situation, saliva samples were collected and assayed for cortisol, a steroid hormone frequently examined in studies of stress. Behavior during the Strange Situation was coded by trained coders, and attachment classifications were determined for each infant. Cortisol concentrations did not differ between the 6 Avoidant/Resistant (A/C) and 17 Securely Attached (B) toddlers. Toddlers (n= 11) who were classified as having Disorganized/Disoriented (Type D) attachments exhibited higher cortisol concentrations than toddlers in the traditional (ABC) classifications. Results of this study were consistent with a model of stress reactivity that conceptualizes the organization of coping behaviors as a factor that mediates physiological stress responses.
Article
To examine the coregulation of positive affect during mother–infant and father–infant interactions, 100 couples and their first-born child were videotaped in face-to-face interactions. Parents' and infant's affective states were coded in one-second frames, and synchrony was measured with time-series analysis. The orientation, intensity, and temporal pattern of infant positive arousal were assessed. Synchrony between same-gender parent–infant dyads was more optimal in terms of stronger lagged associations between parent and infant affect, more frequent mutual synchrony, and shorter lags to responsiveness. Infants' arousal during mother–infant interaction cycled between medium and low levels, and high positive affect appeared gradually and was embedded within a social episode. During father–child play, positive arousal was high, sudden, and organized in multiple peaks that appeared more frequently as play progressed. Mother–infant synchrony was linked to the partners' social orientation and was inversely related to maternal depression and infant negative emotionality. Father–child synchrony was related to the intensity of positive arousal and to father attachment security. Results contribute to research on the regulation of positive emotions and describe the unique modes of affective sharing that infants coconstruct with mother and father. ©2003 Michigan Association for Infant Mental Health.
Article
The role of the mother-toddler attachment relationship in moderating the relations between behavioral inhibition and changes in salivary cortisol levels in response to novel events was examined in 77 18-month-olds. Behavioral inhibition was determined by observing toddler inhibition of approach to several novel events. Attachment security to mother was assessed using the Ainsworth Strange Situation. Changes in salivary cortisol were used to index activity of the stress-sensitive hypothalamic-pituitary-adrenocortical (HPA) system. In addition, toddler coping behaviors and the behaviors used by mothers to help toddlers manage novel events were examined. Elevations in cortisol were found only for inhibited toddlers in insecure attachment relationships. Mothers in these relationships appeared to interfere with their toddlers' coping efforts. These results are discussed in the context of a coping model of the relations between temperament and stress reactivity.
Article
The long-term consequences of early environmental experiences for development have been explored extensively in animal models to better understand the mechanisms mediating risk of psychopathology in individuals exposed to childhood adversity. One common feature of these models is disruption of the mother–infant relationship which is associated with impairments in stress responsivity and maternal behavior in adult offspring. These behavioral and physiological characteristics are associated with stable changes in gene expression which emerge in infancy and are sustained into adulthood. Recent evidence suggests that these long-term effects may be mediated by epigenetic modification to the promoter regions of steroid receptor genes. In particular, DNA methylation may be critical to maternal effects on gene expression and thus generate phenotypic differentiation of offspring and, through effects on maternal behavior of offspring, mediate the transmission of these effects across generations. In this review we explore evidence for the influence of mother–infant interactions on the epigenome and consider evidence for and the implications of such epigenetic effects for human mental health.
Article
Both attachment insecurity and maternal depression are thought to affect infants' emotional and physiological regulation. In the current study, Strange Situation Procedure (SSP) attachment classifications, and cortisol stress reactivity and diurnal rhythm were assessed at 14 months in a prospective cohort study of 369 mother-infant dyads. Maternal lifetime depression was diagnosed prenatally using the Composite International Diagnostic Interview (CIDI). Insecure-resistant infants showed the largest increase in cortisol levels from pre- to post-SSP; the effect was even stronger when they had depressive mothers. Disorganized children showed a more flattened diurnal cortisol pattern compared to nondisorganized children. Findings are discussed from the perspective of a cumulative risk model.
Article
This study sought to replicate previous work in testing the hypothesis that interactions of dyads developing secure attachment relationships would be characterized by disproportionately synchronous and those of dyads developing insecure relationships by disproportionately asynchronous exchanges. Additionally, a priori hypotheses were tested regarding expected differences in the interactional histories of dyads developing insecure-avoidant and insecure-resistant attachments. Results supported the study's predictions in all cases. Dyads developing secure attachments were observed at 3 and 9 months to interact in a disproportionately well-timed, reciprocal, and mutually rewarding manner; dyads developing insecure relationships were disproportionately characterized by interactions in which mothers were minimally involved, unresponsive to infant signals, or intrusive. Within the insecure group, as predicted, 3- and 9-month interactions of avoidant dyads were characterized by maternal intrusiveness and overstimulation; resistant dyads were characterized at both ages by poorly coordinated interactions in which mothers were underinvolved and inconsistent. These findings are discussed as they lend to a growing body of evidence concerning associations between differential interactional histories and attachment quality.
Article
The purpose of this study was to quantify social interaction rhythms in 3- and 5-month-old term and preterm infants and their mothers. Infant-mother dyads were videotaped in a 3-min face-to-face paradigm. For each second of the interaction, separate scores were assigned to infant and mother indicating levels of affective involvement, creating 2 180-sec time series. Spectral and cross-spectral techniques were used to quantify periodicities in each member of the dyad and to estimate the synchrony or coherence of interactional rhythms between each infant and mother. Results showed the existence of periodicities in the behavior of each infant and mother at 3 and 5 months, with most subjects showing spectral peaks between .022 and .10 Hz. Increases from 3 to 5 months in behavioral periodicities were found for infants and mothers as well as for the coherence between infant-mother dyads. Term dyads showed higher coherence than preterm dyads at both 3 and 5 months. Term infants more often led the interaction at both ages. These results were taken as evidence that behavioral periodicities, which may be biologically based, underlie early mother-infant interaction and provide a temporal structure for the organization of cognitive and affective experience. Differences in synchrony between term and preterm infants may explain later reported differences in language between these groups.
Article
Salivary cortisol levels were assessed in 19-month-old infants following the Ainsworth Strange Situation procedure. 38 infants participating in Project STEEP at the University of Minnesota served as subjects. Project STEEP is a longitudinal intervention program designed to promote healthy parent-child relationships and to prevent emotional problems among children born to mothers who are at high risk for parenting problems. Following the Strange Situation, saliva samples were collected and assayed for cortisol, a steroid hormone frequently examined in studies of stress. Behavior during the Strange Situation was coded by trained coders, and attachment classifications were determined for each infant. Cortisol concentrations did not differ between the 6 Avoidant/Resistant (A/C) and 17 Securely Attached (B) toddlers. Toddlers (n = 11) who were classified as having Disorganized/Disoriented (Type D) attachments exhibited higher cortisol concentrations than toddlers in the traditional (ABC) classifications. Results of this study were consistent with a model of stress reactivity that conceptualizes the organization of coping behaviors as a factor that mediates physiological stress responses.
Article
Recent findings from both animal and human research have clearly demonstrated connections between behavioral coping mechanisms and adrenocortical function. The aim of this study was to address the role of maternal sensitivity as an external organizer of psychobiological function in infants during the first year of life. Forty-one infants and their mothers were observed during play at 3, 6, and 9 months of age. Age-specific patterns of relation between maternal sensitivity and infant behavioral organization were found indicating contextual dependence of infant behavior at 3 months and experience-related behavioral function at 9 months. An affect of maternal sensitivity on adrenocortical function during the free play was demonstrated at 3 and 6 months, because an increase in cortisol was most frequently observed in infants of highly insensitive mothers. The findings indicate the importance of maternal behavior for infant biobehavioral organization.
Article
This study examined relations between mother-infant affect synchrony and the emergence of children's self-control. Mother-infant face-to-face play and infant difficult temperament were examined at 3 and 9 months. Maternal and infant affective states at play were coded in 0.25-s frames, and synchrony was computed with cross-correlation functions. Self-control, verbal IQ, and maternal warm discipline were assessed at 2 years. Maternal synchrony with infant affect at 3 months (infant-leads-mother-follows relation) and mutual synchrony at 9 months (cross-dependence between maternal and infant affect) were each related to self-control at 2 years when temperament, IQ, and maternal style were partialed. Infant temperament moderated the relations of synchrony and self-control, and closer associations were found between mutual synchrony and self-control for difficult infants. Shorter lags to maternal synchrony at 3 months were independently related to self-control. The mutual regulation of affect in infancy, as moderated by temperament, is proposed as an important contributor to the emergence of self-regulation.
Article
Individuals with lower socioeconomic status report greater exposure to stressful life events and a greater impact of these events on their lives than individuals with higher socioeconomic status, and this relationship between socioeconomic status and health begins at the earliest stages of life. To extend on these results, we performed a psychoneuroendocrine study of 217 children and 139 mothers. Salivary cortisol levels and cognitive function were assessed in children, and a semistructured phone interview measuring symptoms of stress and depression was conducted with their mothers. Children with low socioeconomic status present significantly higher salivary cortisol levels than children with high socioeconomic status, and this socioeconomic status effect emerges as early as age 6. We also report that a child's cortisol level is significantly correlated with his or her mother's extent of depressive symptomatology. These results offer a neurobiological determinant to the well-known association between socioeconomic status and health that begins early in life.
Article
The phenomenon of infant responsiveness to the caregiver during feeding interactions has been of interest to researchers for many years, because of its associated implications for child growth and development. Although many studies have examined feeding responsiveness in caregiver-infant dyads, it is infrequently and inconsistently defined in the literature. The purpose of this paper is to clarify the concept of infant feeding responsiveness through the provision of a working definition of the concept for further study and usage. Medline, CINAHL, and PschInfo databases from the year 1970 to the present were searched for English articles containing the keywords 'infant', 'feeding', 'responsiveness', 'synchrony', and/or 'interaction'. Articles were selected for inclusion according to whether or not the phenomenon of infant feeding responsiveness was defined or assessed. Walker and Avant's (1995) method for concept analysis was employed for the development of defining attributes, case examples, antecedents, and consequences for further clarification of the concept of infant feeding responsiveness. Infant feeding responsiveness was defined as the manifestation of physiologically influenced visual, expressive, vocal and motor reactive behaviours expressed by an infant in reaction to a caregiver's feeding attempts, indicating a readiness to feed. Implications for nursing are explored as well as the need for refinement of measures of this concept.
Article
Although a great deal is known about physiological responding to stress in nonhuman animals, and also about individual differences in behavioral attunement in humans, physiological attunement between human mothers and their children has never been studied. The current study examined attunement in adrenocortical response between mother and child in the context of the child's exposure to a novel and potentially challenging task. Children ranging in age from two to four years of age walked on a balance beam for the first time while mothers watched on a monitor from the next room. Saliva samples were collected from both mothers and children before and 30 minutes following the beam walk. Individual differences in behavioral attunement were assessed from a videotaped mother-child teaching task, and coded for maternal sensitivity. We expected that mothers rated as highly sensitive would show better physiological attunement with their children's adrenocortical response to the balance beam walk than less sensitive mothers. We did not expect that all children would show a cortisol elevation in response to the task. Rather, we were interested in the degree to which mothers "matched" children's adrenocortical fluctuations, regardless of elevations or decreases in cortisol. Results supported the hypothesis. In the highly sensitive group, mothers' and children's adrenocortical responses to the child beam walk were significantly correlated, and in the less sensitive group the responses were not significantly related. Findings suggest that physiological attunement may co-occur with behavioral sensitivity in normal mother-child relationships.
Article
This study examined infant response and recovery from a social challenge and parent responses. Behavioral and physiological responses were measured from forty-three 5- and 6-month-olds infants during a modified still-face procedure that used an additional still-face reunion sequence. Results confirm the hypothesis that infants of more responsive parents show more regulation than infants of less responsive parents. Infants of more responsive parents showed greater regulation of heart rate and negative affect during the final episode of the procedure than infants of less responsive parents. In addition, this procedure elicited a cortisol response (from .22 microg/dl to .31 microg/dl). Findings suggest important links between parent behavior and infant stress reactivity and regulation.
Article
In mammals the neonatal period is a time of significant social interaction. This is true even in solitary species as females spend a significant amount of time nursing and caring for their offspring. In social species interactions may also include the father, older siblings and extended family members. This period is a time of significant development, including organization of the central nervous system, and therefore a time when the degree and type of social interaction influences the development and expression of social behavior in adulthood. The purpose of this review is to examine the possible mechanisms for the epigenetic effects of early social experience on the subsequent expression of social behavior. We propose that social interactions during the neonatal period organize the subsequent expression of behavior by altering sensitivity to neuropeptides and steroids. Both neuropeptides (e.g. oxytocin and arginine vasopressin) and steroids (e.g. estrogen) regulate or influence the expression of behaviors such as affiliation, aggression, sociosexual behavior, parental behavior, and responses to stress. Therefore, changes in sensitivity to these hormones via reorganization of receptors or changes in hormone production and secretion are potentially powerful mechanisms through which early social experience can mold subsequent social behaviors.
Article
Links between neonatal biological rhythms and the emergence of interaction rhythms were examined in 3 groups (N = 71): high-risk preterms (HR; birth weight <1,000 g), low-risk preterms (LR; birth weight =1,700-1,850 g), and full-term (FT) infants. Once a week for premature infants and on the 2nd day for FT infants, sleep-wake cyclicity was extracted from 4-hr observations and cardiac vagal tone was measured. At term age, infant orientation was tested with the Neonatal Behavior Assessment Scale. At 3 months, arousal modulation and emotion regulation were assessed, and mother-infant synchrony was computed from microanalysis of face-to-face interactions using time-series analysis. Sleep-wake amplitudes showed a developmental leap at 31 weeks gestation, followed by a shift in vagal tone at 34 weeks gestation. At term, differences among FT, LR, and HR infants were observed for biological rhythms in a linear-decline pattern. Sleep-wake cyclicity, vagal tone, newborn orientation, and arousal modulation were each uniquely predictive of mother-infant synchrony. The organization of physiological oscillators appears to lay the foundation for the infant's capacity to partake in a temporally matched social dialogue.
Article
This study used a multiple physiological systems measurement approach to test the hypothesis that asymmetry between the major components of the psychobiology of stress is associated with atypical behavior in youth [Bauer, A.M., Quas, J.A., Boyce, W.T., 2002. Associations between physiological reactivity and children's behavior: advantages of a multisystem approach. J. Dev. Behav. Pediatr. 23, 102-113]. Adolescents (N=67; ages 10-14; 52% male) provided 2 saliva samples before, and 4 samples after, a modified Trier Social Stress Test (TSST; Kirschbaum, C., Pirke, K., Hellhammer, D.H., 1993. The "Trier Social Stress Test": a tool for investigating psychobiological stress responses in a laboratory setting. Neuropsychobiology 28, 76-81). Samples were assayed for cortisol (C) and alpha-amylase (A-A), a surrogate marker of sympathetic nervous system (SNS) activity. Parents/guardians and adolescents reported on adolescents' aggressive behavior. Both salivary A-A and C increased in response to the TSST, with a peak response for A-A immediately post-TSST and for C 10 min post-TSST. A-A and C stress reactivity were estimated using area under the curve (AUC). Asymmetrical C and A-A reactivity accounted for 7% of the variance in parent-reported adolescent aggression. At lower levels of A-A reactivity, lower C reactivity corresponded to higher aggression ratings, but at high A-A reactivity levels, C reactivity was not related to aggression. These results support the hypothesis of Bauer et al. and underscore the importance of a multiple systems measurement approach in biosocial models of adolescent aggression.
Article
Modest genetic effects on morning, but not late-day, cortisol levels have been established. Environmental demands may influence basal cortisol levels later in the day. Thus, we anticipated that individuals in the same family would have similar afternoon cortisol levels to the extent that they share aspects of their environment. We examined afternoon basal cortisol levels measured across 3 consecutive days in mothers and fathers and in multiple offspring in two separate large and longitudinal studies. Study I involved 321 families with singletons while study II involved 233 families with twins. Modest family similarity was apparent for afternoon basal cortisol levels in both studies. Spouses' cortisol levels were also correlated. Data from study II demonstrated that family resemblance in afternoon cortisol was accounted for by underlying shared environmental factors, but not underlying genetic factors. Shared environment accounted for 62% of the variation in twin afternoon basal cortisol levels and 14% of the variation in parent afternoon basal cortisol levels. We used pooled data from the two studies to examine whether parental depression, socioeconomic status (SES), and offspring sex and age impacted cortisol levels. Female offspring had higher cortisol levels than males, and cortisol decreased with age until about 9 years of age, after which cortisol increased with age. Family similarity persisted after accounting for parental depression, SES, time of day, and offspring sex and age, which suggests that the shared family environment influences parent and offspring stress hormone levels throughout the childhood years.
Article
In the history of science, technical advances often precede periods of rapid accumulation of knowledge. Within the past three decades, discoveries that enabled the noninvasive measurement of the psychobiology of stress (in saliva) have added new dimensions to the study of health and human development. This widespread enthusiasm has led to somewhat of a renaissance in behavioral science. At the cutting edge, the focus is on testing innovative theoretical models of individual differences in behavior as a function of multilevel biosocial processes in the context of everyday life. Several new studies have generated renewed interest in salivary alpha-amylase (sAA) as a surrogate marker of the autonomic/sympathetic nervous system component of the psychobiology of stress. This article reviews sAA's properties and functions; presents illustrative findings relating sAA to stress and the physiology of stress, behavior, cognitive function, and health; and provides practical information regarding specimen collection and assay. The overarching intent is to accelerate the learning curve such that investigators avoid potential pitfalls associated with integrating this unique salivary analyte into the next generation of biobehavioral research.
Article
Synchrony, a construct used across multiple fields to denote the temporal relationship between events, is applied to the study of parent-infant interactions and suggested as a model for intersubjectivity. Three types of timed relationships between the parent and child's affective behavior are assessed: concurrent, sequential, and organized in an ongoing patterned format, and the development of each is charted across the first year. Viewed as a formative experience for the maturation of the social brain, synchrony impacts the development of self-regulation, symbol use, and empathy across childhood and adolescence. Different patterns of synchrony with mother, father, and the family and across cultures describe relationship-specific modes of coordination. The capacity to engage in temporally-matched interactions is based on physiological mechanisms, in particular oscillator systems, such as the biological clock and cardiac pacemaker, and attachment-related hormones, such as oxytocin. Specific patterns of synchrony are described in a range of child-, parent- and context-related risk conditions, pointing to its ecological relevance and usefulness for the study of developmental psychopathology. A perspective that underscores the organization of discrete relational behaviors into emergent patterns and considers time a central parameter of emotion and communication systems may be useful to the study of interpersonal intimacy and its potential for personal transformation across the lifespan.
Article
Unfavorable socioeconomic status (SES) circumstances early in life are associated with heightened vulnerability to respiratory and cardiovascular diseases in adulthood. However, little is known about mechanisms underlying this phenomenon. This study examined whether early-life SES predicts future activity of two genes involved in regulating inflammation. An ethnically diverse cohort of 136 adolescent females was enrolled in the study. SES was measured by home ownership. The messenger ribonucleic acid (mRNA) for glucocorticoid receptor (GR) and toll-like receptor 4 (TLR4) was quantified in peripheral blood leukocytes using real-time reverse transcriptase polymerase chain reaction (RT-PCR). Three findings emerged: a) Years 2 to 3 of life were a critical period: the participants whose families owned homes during these childhood years showed higher GR mRNA and lower TLR4 mRNA during adolescence, a profile that suggests better regulation of inflammatory responses. b) These effects were not mediated through current economic circumstances, life stress, or health practices. C) Changes in SES during later years were unable to "undo" these effects. These findings suggest that unfavorable SES circumstances in the early years of life presage the expression of a proinflammatory phenotype in adolescence. To the extent that this proclivity toward inflammation persists over one's lifespan it could explain the heightened incidence of respiratory and cardiovascular disease in low SES populations.
Article
This study investigated the effects of adrenocortical functioning on infant learning during an emotionally challenging event (brief separation from mother). We also explored possible relationships between maternal sensitivity and both infant and maternal cortisol reactivity during the learning/maternal separation episode. Sixty-three 3-month-olds and their mothers were videotaped for a 10 min normal interaction period, and mother-infant behavioral synchrony was measured using Isabella and Belsky's [Isabella, R. A., & Belsky, J. (1991). Interactional synchrony and the origins of infant-mother attachment: A replication study. Child Development, 62, 373-384] coding scheme. The percentage of synchronous behaviors served as a measure of maternal sensitivity. Learning and short-term memory involved relating the infant's mother's voice with a moving colored block in a preferential looking paradigm. Infants whose cortisol increased during the session showed no learning or memory, infants whose cortisol declined appeared to learn and remember the association, while infants whose cortisol did not change evidenced learning, but not memory for the voice/object correspondence. Sensitivity and cortisol reactivity were correlated for mothers, but not for infants. Infant and maternal cortisol values for the first sampling period were highly correlated, but their cortisol reactivity values were uncorrelated, supporting the notion that infants and mothers have coordinated adrenocortical functioning systems when physically together, but become uncoordinated during a separation/learning event.
Article
Tobacco smoke exposure affects the activity of both the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). Statistics reveal 41 million children in the U.S. are regularly exposed to tobacco smoke, but we know little about the effects of environmental tobacco smoke exposure on HPA and SNS activity in early childhood. This study assayed cotinine (a metabolite of nicotine), cortisol, and alpha-amylase (sAA) in the saliva of mother-infant dyads from 197 low income and ethnically diverse families. The dyads were identified as tobacco smoke exposed (N = 82) or nonexposed (N = 115) based on maternal self-reports of smoking and salivary cotinine levels greater or less than 10 ng/ml. As expected, higher rates of maternal smoking behavior were associated with higher levels of cotinine in mothers' and their infants' saliva. On average, smoking mothers' salivary cotinine levels were 281 times higher compared to their nonsmoking counterparts, and 23 times higher compared to their own infant's salivary cotinine levels. Infants of smoking mothers had salivary cotinine levels that were four times higher than infants with nonsmoking mothers. Mothers who smoked had higher salivary cortisol levels and lower sAA activity compared to nonsmoking mothers. There were no associations between maternal smoking behavior, infant's salivary cotinine levels, or tobacco exposure group, and cortisol or sAA measured in infant's saliva. The findings are discussed in relation to the influence of smoking tobacco on the validity of salivary biomarkers of stress.
Article
Disorganized attachment is an early predictor of the development of psychopathology in childhood and adolescence. Lyons-Ruth et al. (1999) developed the AMBIANCE coding scheme to assess disrupted communication between mother and infant, and reported the link between maternal behavior and disorganized attachment. The Hungarian group found an association between a polymorphism of the DRD4 gene and disorganized attachment (Lakatos et al., 2000; 2002; Gervai et al., 2005). The present collaborative work investigated the interplay between genetic and caregiving contributions to disorganized attachment. 138 mother-infant dyads, 96 from a Hungarian low-social-risk sample and 42 from a US high-social-risk sample, were assessed for infant disorganized attachment behavior, for DRD4 gene polymorphisms, and for disrupted forms of maternal affective communication with the infant. In accord with literature reports, we found a robust main effect of maternal AMBIANCE scores on infant disorganization. However, this relation held only for the majority of infants who carried the short form of the DRD4 allele. Among carriers of the 7-repeat DRD4 allele, there was no relation between quality of maternal communication and infant disorganization. This interaction effect was independent of degree of social risk and maternal DRD4 genotype.
Article
Sethre-Hofstad et al. [2002, Psychoneuroendocrinology 27:731-747] found that behaviorally well-attuned or sensitive parents showed better physiological attunement with their 2- to 4-year-old toddlers' adrenocortical responses to a potentially challenging task than less sensitive parents. In the present study we aimed to replicate this finding in a sample of 83 parents with 15-month-old infants. Parental and infant cortisol responses were assessed using saliva samples collected before and 21 min after the child's confrontation with a stranger and a moving robot. Infant behaviors reflecting distress/uncertainty during the stranger-robot session were rated from videotape. Parental sensitivity was observed during a parent-infant teaching episode. Our findings replicate those of Sethre-Hofstad et al. [2002, Psychoneuroendocrinology 27:731-747] by showing correlated parent-infant cortisol responses for sensitive parents but not for less sensitive parents. Furthermore, sensitive parents cortisol responses were associated with their children's distress/uncertainty during the stranger-robot episode, whereas this was not true for less sensitive parents. Results indicate an important connection between behavior and physiology in parent-infant interactions that deserve more research.
Defining and assessing individual differences in attachment relationships: Q-methodology and the organization of behavior in infancy and early childhood. In: Bretherton I, Waters E, editors. Growing points of attachment theory and research
  • Waters E Deane
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