Infant Behavior and Development

Published by Elsevier
Online ISSN: 0163-6383
Publications
Article
The present study investigated the degree to which an infants' use of simultaneous gesture-speech combinations during controlled social interactions predicts later language development. Nineteen infants participated in a declarative pointing task involving three different social conditions: two experimental conditions (a) available, when the adult was visually attending to the infant but did not attend to the object of reference jointly with the child, and (b) unavailable, when the adult was not visually attending to neither the infant nor the object; and (c) a baseline condition, when the adult jointly engaged with the infant's object of reference. At 12 months of age measures related to infants' speech-only productions, pointing-only gestures, and simultaneous pointing-speech combinations were obtained in each of the three social conditions. Each child's lexical and grammatical output was assessed at 18 months of age through parental report. Results revealed a significant interaction between social condition and type of communicative production. Specifically, only simultaneous pointing-speech combinations increased in frequency during the available condition compared to baseline, while no differences were found for speech-only and pointing-only productions. Moreover, simultaneous pointing-speech combinations in the available condition at 12 months positively correlated with lexical and grammatical development at 18 months of age. The ability to selectively use this multimodal communicative strategy to engage the adult in joint attention by drawing his attention toward an unseen event or object reveals 12-month-olds' clear understanding of referential cues that are relevant for language development. This strategy to successfully initiate and maintain joint attention is related to language development as it increases learning opportunities from social interactions. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
Infants expect people to direct actions toward objects, and they respond to actions directed to themselves, but do they have expectations about actions directed to third parties? In two experiments, we used eye tracking to investigate 1- and 2-year-olds' expectations about communicative actions addressed to a third party. Experiment 1 presented infants with videos where an adult (the Emitter) either uttered a sentence or produced non-speech sounds. The Emitter was either face-to-face with another adult (the Recipient) or the two were back-to-back. The Recipient did not respond to any of the sounds. We found that 2-, but not 1-year-olds looked quicker and longer at the Recipient following speech than non-speech, suggesting that they expected her to respond to speech. These effects were specific to the face-to-face context. Experiment 2 presented 1-year-olds with similar face-to-face exchanges but modified to engage infants and minimize task demands. The infants looked quicker to the Recipient following speech than non-speech, suggesting that they expected a response to speech. The study suggests that by 1 year of age infants expect communicative actions to be directed at a third-party listener. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
Latent growth modeling (LGM) was used to examine the contribution of changes in infant orienting/regulation (O/R) to the emergence of toddler effortful control (EC), the contributions of maternal EC to the development of infant O/R and the emergence of toddler EC, the influence of maternal time spent in caregiving activities on toddler EC and the slope of infant O/R, and the contribution of maternal EC to subsequent maternal time spent in caregiving activities. Mothers from 158 families completed a self-report measure of EC when their infants were 4 months of age, a measure of infant O/R when their infants were 4, 6, 8, 10, and 12 months of age, and a measure of toddler EC when their children reached 18 months of age. Information concerning maternal time spent in various interactive caregiving activities was collected when infants were 6 months old. Results indicated higher maternal EC predicted interindividual differences in the intercept (i.e., higher intercepts), but not slope, of infant O/R and that higher maternal EC, higher infant O/R intercept, and higher infant O/R slope contributed to higher toddler EC. Furthermore, higher maternal EC predicted greater maternal time spent in interactive caregiving activities with their infants and greater maternal time in interactive caregiving with infants also contributed to higher toddler EC after controlling for maternal EC. These findings contribute to the understanding of the influence of maternal EC, directly and through caregiving, on toddler EC. Additional implications as they are related to early developing regulatory aspects of temperament are discussed.
 
Article
There has been increasing interest in the direct and indirect effects of parental self-regulation on children's outcomes. In the present investigation, the effects of maternal self-regulation, home chaos, and inter-parental relationship adjustment on broad and specific indicators of infant negative emotionality (NE) were examined. A sample of maternal caregivers and their 4-month-old infants (N=85) from a rural community participated. Results demonstrated that better maternal self-regulation was associated with lower infant NE broadly, as well as with lower infant sadness and distress to limitations/frustration and better falling reactivity (i.e., emotion regulation), specifically. Maternal self-regulation also predicted less chaotic home environments and better maternal inter-parental relationship adjustment. Findings also supported the indirect effects of maternal self-regulation on broad and specific indicators of infant NE through home chaos and maternal relationship adjustment. Some differential effects were also identified. Elevated home chaos appeared to specifically affect infant frustration/distress to limitations whereas maternal relationship adjustment affected broad infant NE, as well as several specific indicators of infant NE: frustration/distress to limitations, sadness, and falling reactivity. In conjunction with other recent investigations that have reported the effects of maternal self-regulation on parenting, the findings in the present investigation suggest that parental self-regulation may influence children's outcomes through several proximal environmental pathways.
 
Article
Eighty-three mother-infant dyads participated in this study. Positive affect (PA) broadly, along with fine-grained aspects of PA, was measured at 10 months of age. Language was measured at 14 months. Infant PA predicted expressive, but not receptive, language. The implications of these findings are discussed.
 
Article
Caregivers modify their communication when interacting with infants, and these modifications have been related to children's language development. However, the factors influencing caregivers' modification of gestures are understudied. This study examined whether infants' object knowledge, considered as common ground shared with the caregiver, relates to caregivers' gesturese. Six caregiver-infant dyads were videotaped every two months for 15min in their homes, from child age 8-to-16 months, while they played with two separate objects (i.e. toys). Results indicated that the changes in infants' object knowledge were paralleled by associated changes in caregivers' gestures: parents increased both the amount and the complexity of their gestures.
 
Article
Infants and children have difficulty categorizing objects in new contexts. However, learning in both same and varied contexts can help young word learners overcome contextual learning difficulties. We examined the relation between infants' visual attention to the category member and background context during learning and their ability to generalize a new category member in a new context. Of particular interest is how this relation is affected by learning in various contextual conditions. Infants (16-20 months; n=48) were presented with eight novel noun categories in one of three contextual conditions (same context, varied context, or a combination of same and varied contexts), and tested for their generalization ability in a new context. Context was defined as the colored and patterned fabric upon which the object was presented. Results suggest that visual attention during learning is associated with category generalization ability in a new context only for infants whose learning took place in a combination of same and varied background contexts. The results are discussed in terms of the mechanisms by which context affects generalization. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
Although the relationship between biological motion perception as depicted by point-light displays and social cognition has been investigated in recent decades, the developmental course of the integration of social cognition and the perception of biological motion is not well understood. To better understand this development, we investigated the ability of 9- and 12-month-old infants to shift their gaze toward a point-light upright human figure using a paradigm similar to that used by Yoon and Johnson (2009). We found that 12-month-old, but not 9-month-old, infants were able to follow the direction of attention of the upright point-light figure (Experiments 1 and 2). However, both the younger and older infants were able to follow the attentional shift of others under the full-view condition (Experimental 3). These results suggest that the ability to process the higher-level information provided by biological motion patterns, such as the attentional direction of others, develops by 12 months, but not by 9 months, of age. The relationship between the development of social cognition and that of biological motion perception is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
In the current study, latent growth modeling (LGM) was used to: (1) identify the developmental trajectories of infant negative emotions (NE) and regulatory capacity (RC) from 4 to 12 months of age, (2) examine maternal and family factors that may affect NE and RC trajectories, (3) examine transactional associations between developing NE and RC, and (4) examine the effect of infant temperament trajectories on negative parenting when toddlers reached 18 months of age. Mothers from 156 families completed a measure of infant temperament when infants were 4, 6, 8, 10, and 12 months of age and completed maternal relationship stress, depression, and family demographics measures when infants were 4 months of age. Information regarding negative parenting was collected when toddlers reached 18 months of age. LGM results suggest that maternal relationship stress and depression influence infant NE development, that high NE early in infancy may compromise the development of infant regulation, and that steeper decreases of infant RC contribute the greatest amount of variance to negative parenting in toddlerhood. The implications for models of early emotion regulation and incorporating changes in temperament over time into developmentally sensitive models (e.g., emerging parenting practices and developmental psychopathology) are discussed.
 
Article
This study investigated the factor structure of observational indicators of children's temperament that were collected across the first three years of life in the Family Life Project (N=1205) sample. A four-factor model (activity level, fear, anger, regulation), which corresponded broadly to Rothbart's distinction between reactivity and regulation, provided an acceptable fit the observed data. Tests of measurement invariance demonstrated that a majority of the observational indicators exhibited comparable measurement properties for male vs. female, black vs. white, and poor vs. not-poor children, which improved the generalizability of these results. Unadjusted demographic group comparisons revealed small to moderate sized differences (Cohen ds=|.23-.42|) in temperamental reactivity and moderate to large sized differences (Cohen ds=-.64--.97) in regulation. Collectively, demographic variables explained more of the variation in regulation (R(2)=.25) than in reactivity (R(2)=.02-.06). Follow-up analyses demonstrated that race differences were substantially diminished in magnitude and better accounted for by poverty. These results help to validate the distinction between temperamental reactivity and regulation using observational indicators. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
Positive engagement activities support children's adaptive development and new parents are encouraged to be highly engaged with infants. Yet, fathers' engagement is widely understudied and maternal engagement quantity is frequently overlooked. Our study contributes to growing knowledge on associations between infant temperament and parental engagement by testing transactional and moderation models in a recent sample of first-time parents when infants were 3, 6, and 9 months old. Stringent longitudinal, reciprocal structural equation models partially confirmed an engagement "benefit". Mothers' engagement marginally contributed to their children's gains in effortful control from 3 to 6 months regardless of child gender. Further, mothers' engagement reduced infant negative affect from 6 to 9 months regardless of child gender. Mothers' ratings of infant negative affect were gendered; mothers' ratings of infant negative affect increases more from 3 to 6 months for boys. Fathers' engagement was contextually sensitive; child gender moderated the link between negative affect and engagement from 6 to 9 months, such that fathers became more engaged with boys whom they rated higher on negative affect; there was no effect for daughters. Finally, we found that effortful control moderated associations between negative affect and maternal engagement; mothers' engagement increases from 3 to 6 months were greater for children initially rated lower in effortful control. Implications for future research and parenting education and support services are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.
 
Article
Although "late preterm" (LP) newborns (33-36 weeks of gestational age) represent more than 70% of all preterm labors, little is known about the relation between certain risk factors and developmental outcomes in LP compared to "very preterm" (≤32 weeks) children (VP). This study investigates: (1) LP and VP infants' development at 12 months of corrected age (CA) using the Bayley Scales of Infant Development - 3rd Edition (BSID-III); (2) correlation between BSID-III performances and maternal stress (using Parenting Stress Index-Short Form, PSI-SF) among LP and VP at 12 months CA; and (3) the link between known neonatal and demographic risk factors and developmental outcomes of LP and VP infants. For both LP and VP infants the Mean Cognitive (LP: 102.69±7.68; VP: 103.63±10.68), Language (LP: 96.23±10.08; VP: 99.10±10.37) and Motor (LP: 91.11±10.33; VP: 93.85±10.17) composite scores were in the normal range, without significant differences between the groups. Correlations between PSI-SF and BSID-III showed that in the VP group (but not LP), Language score was negatively related to the PSI-SF 'Difficult Child' scale (r=-.34, p<.05). Regression models revealed that cognitive performance was significantly predicted by physical therapy in LP and by cesarean section in VP infants. For VP only maternal education and length of stay predicted Language score, whereas physical therapy predicted Motor score. Results of the study underline the importance of considering cognitive, language and motor developments separately when assessing a preterm child's development. Prediction models of developmental performance confirm the influence of some known neonatal risk factors and indicate the need for further research on the role of sociodemographic risk factors. Copyright © 2015 Elsevier Inc. All rights reserved.
 
Article
This study explores whether transitional skills and sitting correlate with locomotion onset. The development of eight infants was followed. Most transitional skills correlated with locomotor skills. Sitting and rolling did not. Transitional skills may resemble the control needed for locomotion more closely than sitting. Copyright © 2014 Elsevier Inc. All rights reserved.
 
Article
The purpose of the current study was to longitudinally examine the relations between general characteristics of maternal behavior and the degree to which infants demonstrate an ability to regulate arousal. Thirty-two infant-mother dyads were visited at home and videotaped in two 3-min episodes of face-to-face interaction at 1 and 4 months infant age. Infant gaze behavior, head orientation, and facial expressions provided a composite index of infant arousal regulation. Results revealed positive within- and across-time associations between maternal interactive behaviors and infants' arousal-regulating abilities. Two features of 1-month maternal beahavior—state and physical activity—were highlighted in the prediction of 4-month infant arousal regulation. More specifically, hierarchical regression analyses revealed that these 1-month maternal behaviors accounted for a significant percent of the variance in 4-month infant arousal regulation, whereas earlier infant arousal regulation and concurrent maternal behaviors made insignificant contributions.
 
Article
The visual-tactual knowledge of 8, 9½, and 11-month-old infants was assessed by comparing their responses on two sorts of “trick” trials to those on matched control trials. On the virtual object task, the infants felt nothing at all where they could see an object on the trick trial, and they felt the visible object on the control trial. On two cross-modal tasks, the infants felt something different in shape and texture from what they could see in a certain place on trick trials, and they felt an object identical to the one seen an control trials. The two older groups of infants responded differentially to the trick and control trials, while the 8-moth-olds did not. It is concluded that 9½ and 11-month-old infant posses visual tactual knowledge about both object existence and object feature. The failure of 8-month-olds to similarly evidence such knowledge is discussed with reference to their less mature information processing abilities and reaching skills
 
Article
Response decrement and recovery were compared using fixed-trial and infant-control habituation procedures. Infants who had experienced perinatal difficulties (e.g., respiratory distress, jaundice) were tested at 6 to 13 months of age. Post hoc rescoring of the fixed-trial data according to infant-control rules showed similar baseline responding and decrement scores for two procedures, although the infant-control group made more frequent and longer looks at the stimulus. A response to novelty was obtained only for the infant-control procedure. Risk severity did not emerge as a significant factor. The findings are discussed with reference to contingency effects operating in infant-control and procedure-specific sensitization. It was concluded that infant-control and fixed-trial habituation paradigms offer alternative procedural routes for studying representational competence in infancy.
 
Article
Five times between early pregnancy and 13.5 months postpartum, 29 primiparous and 40 multiparous parents completed the Infant Characteristics Questionnaire (ICQ). Stability was evident for all factors within pregnancy, especially for Factors I and II within the postpartum period, and most consistently for Factors II and IV between pregnancy and postpartum phases. All significant correlations were between .46 and .89. Differences between multiparous and primiparous parents, and between mothers and fathers, in the magnitude and pattern of stability coefficients were found.
 
Article
Attachment at 14 months of age was examined in a sample of infants who had been selected for high or low levels of positive or negative affective reactivity and motor activity at 4 months of age. The type of early emotional reactivity was not clearly associated with attachment security or insecurity. The proposal of Belsky and Rovine [Belsky, J., & Rovine, M. (1987). Temperament and attachment security in the strange situation: An empirical rapprochement. Child Development, 58, 787–795] that infants classified as B3/B4 or C1/C2 are temperamentally more negatively reactive than those classified as A1/A2 or B1/B2 was supported. Compared with infants who showed high levels of positive affect and infants who scored low on affective reactivity, infants who showed high levels of negative affect in response to stimulation at 4 months of age were significantly more likely to be classified as B3/B4 or C1/C2 in the Strange Situation at 14 months of age. These findings are discussed in the context of prior inconsistent findings about the relations between temperament and groups of attachment sub-classifications. The role of different methods of assessing temperament and the importance of selected samples in clarifying such relations is discussed.
 
Article
The influence of changes in context and object characteristics on deferred imitation was assessed in 14-month-old infants. In Experiment 1, infants in the imitation group saw an adult demonstrate target acts on miniature objects in an unusual context (an orange polka-dot tent). When later presented with larger objects in a normal laboratory room, these infants performed significantly more target acts than did controls. In Experiment 2, three groups of infants were tested. Infants in an imitation(no change) group saw an adult demonstrate target acts and were subsequently tested in the same room using the same objects as the adult. Infants in the imitation (context + object size & color change) group followed the same procedure, but both the context and two salient featural characteristics of the objects (size and color) were changed between encoding and the recall test of deferred imitation. Control infants did not see the target demonstrations. Results showed that the combined changes in context and object features led to a significant decrease in imititive performance. Nonetheless, in comparison to the controls, infants exhibited significant recall as indexed by deferred imitation. The results show that imitation generalizes across changes in object size, object color, and test context. The implications for theories of memory and representational development are discussed.
 
Article
Measures of respiratory sinus arrhythmia (RSA) in R-R intervals were calculated from a 5-min recording of 3- to 6-month-old full-term infants. The reliability of the measures was estimated with Cronbach's α for sampling durations of 5, 15, 25, or 60 s, for single or multiple samples from each of the five baseline periods. Reliability of RSA was good (>.8) for samples of 25 s or greater but decreased with smaller sampling durations. The sensitivity of the measures in detecting an age effect between 14-, 20-, and 26 week-old infants correlated positively with the reliability of the measure. This study suggests that reliability of RSA measures in young infants is acceptable.
 
Article
This study reports on maternal perceptions of emotion in their own infants. Concurrent and retrospective estimates of emotion onset were obtained from 597 mothers of infants who varied in age from 1 through 18 months. Information was also obtained about the frequency with which mothers perceived emotions in themselves and in their infants. Unexpectedly, a substantial number of emotions were reported in young infants. During the first three postnatal infant months, a majority of mothers reported the presence of five of the 11 emotion categories studied (interest, joy, surprise, anger, and distress). Another study of 26 mothers of newborns found similar results concerning the prevalence of perceived emotions. Age trends and possible explanations for the high frequency of perceived emotions in early infancy are discussed. An important issue is to what extent mothers relied on infant behaviors and to what extent they made use of contextual cues.
 
Article
The current study was a replication and extension of a study of infant imitative learning by Meltzoff (1995). Unlike the 18-month-old infants in that study (and other 18-month-olds in the current study), the 12-month-olds in this study did not frequently imitate unsuccessful goal-directed actions. Also, both 12- and 18-month-old infants reproduced actions more often when they observed the entire action and its result than when they observed the result only.
 
Article
Competing data exist regarding the influence of child care arrangements on infant social development. Yet, a large amount of within-group variability for both nonmaternally cared for infants and infants cared for in their homes by their mothers has been found with regard to such social developmental outcomes as attachment. The present study assessed coping as a mediator in the relationship between parenting stress and attachment for 32 families consisting of a mother, father, and their 18-month-old infant. The Attachment Q-Set, Parenting Stress Index, and Ways of Coping were administered. Parenting stress was significantly associated with insecure attachment to mothers and fathers. It was indicated that psychological separation (due to stress) more than actual physical separation (due to child care arrangements) may be a salient variable in considering the impact of child care on the relationship between infants and their parents. Positive reappraisal, as a coping strategy, was related to substantial reductions in the associations between parenting stress and attachment security. Although the results are not causal, implications for prevention efforts were suggested based on the coping strategies that were adaptive in mediating parenting stress versus those that were not.
 
Article
In recent years, the investigation of social transactional factors in early language and prelinguistic development have played an important role in reshaping concepts of communication and its ontogenesis. The present study reports findings concerning young infants' dispositions to follow the conversational interchanges of spontaneous adult dialogues. Two of 13 12-week-old infants (15%) and 8 of 12 18-week-old infants (67%) showed organized shifts in visual attentiveness that were co-incident with shifts in speaking that occurred between adult speakers. Conversation monitoring of this sort went on in some instances for as long as 2 to 3 min. The data are discussed from the standpoints of cognition-attention, affect, and subjectivity.
 
Article
This study explored infants' ability to discriminate between, and their tendency to reproduce, the accidental and intentional actions of others. Twenty 14- through 18-month-olds watched an adult perform a series of two-step actions on objects that made interesting results occur. Some of the modeled actions were marked vocally as intentional (“There!”), some were marked vocally as accidental (“Woops!”). Following each demonstration, infants were given a chance to make the result occur themselves. Overall, infants imitated almost twice as many of the adult's intentional actions as her accidental ones. Infants before age 18 months thus may understand something about the intentions of other persons. This understanding represents infants' first step toward adult-like social cognition and underlies their acquisition of language and other cultural skills.
 
Article
Amniotic fluid, obtained from 87 pregnant women for routine amniocentesis, was analysed for foetal testosterone (FT) level. Their infants (40 girls and 47 boys) were followed up 18 and 24 months after birth and their vocabulary size was assessed. Girls were found to have a significantly larger vocabulary than boys at both ages. This replicates previous findings of a female advantage in language ability, but reveals this sex difference at the earliest point of development. Additionally, FT was an inverse predictor of vocabulary size when data from both sexes was examined together, but not within sex. The lack of a significant correlation between FT and vocabulary within each sex may reflect the relatively small sample size. However, the significant correlation between FT and vocabulary when the sexes were combined suggests FT might be involved in shaping the neural mechanisms underlying communicative development.
 
Article
Selective impairments have been found in the ability of language impaired (LI) children to process the rapidly changing temporal cues critical to language comprehension and production. Performance on temporal perception and production tasks alone enable correct identification of 98% of LI from normal children. These findings suggest that auditory temporal processing (ATP) deficits might serve as a behavioral “marker” of language impairment and could be useful in early identification. Measures of perceptual-cognitive abilities in infancy such as habituation and recognition memory have been shown to be particularly sensitive to language delays. Specific links have been demonstrated between these measures and language comprehension. We hypothesize that a critical mechanism contributing to “speed of processing,” as measured by rate and amount of habituation and novelty preference on recognition memory tests, may be temporal processing efficiency in infancy. Auditory temporal processing thresholds were examined in two groups of infants from 6 to 10 months of age: infants from families with no known history of LI and infants from families with a positive history of LI. Infants from families with a positive history of LI had significantly lower mean thresholds than control infants. Habituation, ATP thresholds, and recognition memory were found to be significantly associated suggesting that they may be tapping similar processes.
 
Article
The aim of this study was to examine the validity of activity-based monitoring (actigraphy) for the assessment of sleep-wake patterns during the 1st year of life. Forty-one infants were directly observed for sleep-wake state determination by trained observers. Concomitant activity data obtained by actigraphs attached to the infants' ankles during the observation were matched on a minute-by-minute basis, and a scoring algorithm was developed for automatic identification of sleep-wake states. Overall, the automatic scoring algorithm for activity data reached 95.3% agreement rate with the observers' sleep-wake scoring. Distinction of quiet and active sleep reached agreement rates ranging from 54% to 87% at different ages. Significant night-to-night stability was found for several derived sleep-wake measures, and high variability was noted for other measures. It is concluded that actigraphy provides valid sleep-wake measures during the 1st year of life.
 
Article
In Experiment 1, 6-month-old infants looked longer in order to listen to a set of consonant intervals than to a set of dissonant intervals. In Experiment 2, infants preferred to listen to the original version of a Mozart minuet than to a version altered to contain many dissonant intervals. Thus, although infants do not yet have the musical-system-specific knowledge of scale structure that is involved in adults' emotional reactions to music, infants are similar to adults in their evaluative reactions to consonance and dissonance.
 
Article
Developmental changes in imitation were examined in three experiments with 6- to 24-month-old infants. In all experiments, infants in the demonstration condition observed an experimenter perform three specific actions with a puppet. Their ability to reproduce those actions was assessed for the first time during the test in the absence of prior practice. Infants in the control condition received equivalent exposure to the puppet and the experimenter but were not shown the target actions. The results of Experiment 1 showed that 12-, 18-, and 24-month-old infants exhibited clear evidence of imitation following a 24-hour delay (deferred imitation). In addition, the findings of Experiment 1 demonstrated that the 18- and 24-month-old infants reproduced more of the target actions during the test than the 12-month-olds. The results of Experiment 2 showed that 6-month-olds performed as well as 12-month-olds when they were tested in the absence of a delay (immediate imitation). Finally, the results of Experiment 3 showed that, with additional exposure to the target actions, even 6-month-old infants exhibited deferred imitation following a 24-hour delay. Taken together, these findings have important implications for current theories of the development of imitation and memory during the first 2 years of life.
 
Article
Parents' subjective reactions to specific temperament-related behaviors perceived in their young children were assessed in this study as a means of obtaining a parental perspective on the definition of easiness/difficultness. Mothers and fathers of 60 children, either 6 or 24 months old, completed a standardized temperament questionnaire and, subsequently, a follow-up questionnaire that requested ratings of how pleasing they found specific behaviors representing the New York Longitudinal Study (NYLS) easy/difficult dimensions. The highest correlations between temperament ratings and pleasure ratings, for both mothers and fathers, were obtained for Mood and Adaptability, indicating the significance of these dimensions for parents. Examination of the possible moderating effects of child classification variables (age, birth order, and gender) on these relationships indicated that, in general, correlations between temperament and pleasure ratings are not different under different child conditions. The implications of these results for the construct of easiness/difficultness are discussed.
 
Article
To determine the effects of maternal methadone maintenance during pregnancy on the young child we have longitudinally followed 2 groups of children: one born to mothers on methadone maintenance and a second group born to drug-free mothers. The following report describes our findings during a follow-up assessment at 24 months of age and compares them with a previous assessment at 12 months of age. The findings in the methadone children include no differences in somatic growth except a higher incidence of head circumferences below the third percentile; neurological signs of nystagmus/strabismus, tone and coordination abnormalities and developmental delays; lower mean scores on the Bayley MDI and PDI at 12 months of age and PDI scores at 24 months of age with a greater number of scores below 85. Thus, maternal methadone maintenance places the infant at high risk for future neurobehavioral problems.
 
Article
This study describes a revision of a widely used parent-report measure of infant temperament, the Infant Behavior Questionnaire (IBQ; Rothbart, 1981). A rationally derived instrument was developed that included nine new scales and minor modifications of the seven scales of the IBQ. Parents of 360 infants, equally distributed over three age groups: 3–6 months; 6–9 months; and 9–12 months of age, participated. Conceptual and item analyses provided support for 14 of the 16 proposed scales, demonstrating satisfactory internal consistency. Inter-rater reliability was evaluated, with evidence of moderate agreement between primary and secondary caregivers. Monomethod discriminant validity was demonstrated through an examination of correlations among the Infant Behavior Questionnaire—Revised (IBQ-R) scale scores. Results of the factor analytic procedure were consistent with three broad dimensions of Surgency/Extraversion, Negative Affectivity, and Orienting/Regulation. Developmental and gender differences were also noted for a number of the IBQ-R scales. Specifically, older infants received higher scores on Approach, Vocal Reactivity, High Intensity Pleasure, Activity, Perceptual Sensitivity, Distress to Limitations, and Fear, whereas younger infants’ scores were higher for Low Intensity Pleasure, Cuddliness/Affiliation, and Duration of Orienting. Male infants obtained higher scores on Activity and High Intensity Pleasure, and female infants were rated higher on the Fear scale.
 
Article
This article reports the results of an intensive, longitudinal investigation of the development of infants’ ability to shift gaze from a central to a peripheral stimulus. Sixteen infants were followed at 2-week intervals from 6 to 26 weeks of age. A high degree of discontinuity was found in the development of both frequency and latency of shifts of gaze, with rapid improvement between 9 and 16 weeks, followed by more gradual improvement between 16 and 26 weeks. Individual developmental trajectories for frequency were highly similar to the group trajectory. Trajectories for latency cost differed more across infants. Inter-infant differences had not become stable for either measure at 26 weeks. The findings are consistent with explanations of the development of gaze shifting in terms of changes in the relative strength of processes which maintain the focus of attention and gaze, and processes which interrupt and shift it.
 
Article
This study examined the effect of stimulus movement on localization probability and latency during attention and inattention. Forty infants, 10 each at 8, 14, 20, and 26 weeks of age were presented with a central stimulus. Then, a peripheral stimulus was presented (static or dynamic checkerboard). Stimulus movement did not affect localization probability. Infants localized the dynamic peripheral stimulus more quickly than the static peripheral stimulus when there was no focal stimulus. Focal stimulus attention attenuated this difference in localization latency between static and dynamic stimuli. Signal detection analysis showed that sensitivity to the peripheral stimulus increased over this age range along with a decrease in the bias against responding. The effects of attention were on response bias rather than stimulus sensitivity. These results imply attention affected the localization response to the peripheral stimulus but did not affect the sensitivity of the sensory and perceptual pathways to peripheral stimuli.
 
Article
Many studies have examined infants perception of the third dimension or the preference for 3-dimensional (3D) vs. 2-dimensional (2D) stimuli. However, little is known about the infant’s capacity for efficient representation of the third dimension in a 2D display. Young infants appear to be able to perceive 3D displays, but whether they are able to use interposition and perspective indices to represent 3D shapes is unknown. The present study examined this issue with a 2D adaptation of Baillargeon, Spelke, and Wasserman’s (1985) drawbridge experiment. The results were similar to those obtained in the original study. In a control experiment where the object was at the side of the screen, no difference in looking duration was observed between the 180 and 112° events. These results provide a replication of Baillargeon et al.’s original experiment. They also show that 4-month-olds use 2D display information in a manner similar to adults.
 
Article
Rossavik models [P = c(t) k+s(t)] were used to characterize behavioral development in 306 infants without evidence of brain injury, evaluated at approximately 3 month interval from 4 to 25 months (age adjusted for prematurity). Mental Development (MD) and Psychomotor Development (PD) raw scores from BSID-I and BSID-II were utilized. Separate Rossavik models specified from raw scores obtained before 418 days were used to predict raw scores after 418 days. Predictability was measured by calculating % Deviations (actual - predicted/predicted × 100). Rossavik models fit complete data sets from individual infants quite well with little variation [R2: BSID-I 98.5 +/- 1.3% (MD), 97.7 +/- 2.0% (PD); BSID-II 98.8 +/- 1.0%, 9 (MD), 98.2 +/- 1.6% (PD)]. Models derived from 1st year raw scores predicted 2nd year raw scores with a random error of +/- 10% or less. Predicting 2nd year development from 1st year data were evaluated using three other models. The results obtained were less accurate and/or more variable than those obtained with Rossavk models. We concluded that Rossavik models accurately characterize behavioral development in the first 2 years and can be used to predict 2nd year scores with sufficient accuracy to allow specification of individualized developmental trajectories.
 
Article
Individual differences in infants’ attentional style at 3.5 months are only moderately stable across the first postnatal year. However, infants designated as short lookers based on a pattern examination pretest task at 3.5 months had better recognition memory at 1 year and were briefer in toy examination on post-habituation tests than were long lookers. When these infants were 8–12 months old, peak-look duration during habituation was a better predictor of concurrent task performance than was the original pattern examination task when given at the follow up. Short and long lookers did not differ on a deferred imitation task.
 
Article
This study evaluates the relation between Type I (symmetrical) intrauterine growth retardation (IUGR) and subsequent growth patterns during the first year of life and cognitive development in a group of children at 36, 48, and 60 months of life. Growth parameters of normal-birthweight children were compared to those of low-birthweight children having symmetrical growth (adequate ponderal index) in relation to cognitive outcome measures. Only at 36 months did IUGR show an independent association with verbal cognitive abilities. At 36 and 48 months, an interaction between IUGR and growth during the first year of life was associated with performance on measures of short-term memory. At 60 months, the effects of IUGR are not evident; however, estimates of low statistical power may also explain the absence of differences at this age.
 
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The behaviors of dual-career parents were compared in face-to-face interactions with their 8-month-old infants who attended on all-day infant nursery. Mothers, as compared to fathers, exhibited more frequent smiling, vocalizing, and touching with their infants. In turn, the infants spent a greater proportion of the interaction time smiling and being motorically active when they were interacting with their mothers versus their fathers.
 
Top-cited authors
Janet F. Werker
  • University of British Columbia - Vancouver
Richard C Tees
  • University of British Columbia - Vancouver
Anne Fernald
  • Stanford University
Anthony J. Decasper
  • University of North Carolina at Greensboro
Andrew N Meltzoff
  • University of Washington Seattle