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Dopamine in the medial amygdala network mediates human bonding

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Abstract

Significance Early life bonding in humans has critical long-term implications for health, productivity, and well-being in society. Nonetheless, neural mechanisms of bonding are typically studied in rodents, and no studies to date had examined the neurochemistry of human social affiliation. This study utilizes a state-of-the-art technology to demonstrate that human maternal bonding is associated with striatal dopamine function and the recruitment of a cortico–striatal–amygdala brain network that supports affiliation. The simultaneous probing of neurochemical responses and whole-brain network function in mothers watching their infants provides a unique observation into an “affiliating brain.” These results advance the mechanistic understanding of human social bonding and promote basic and clinical research in social neuroscience, development, and psychopathology.

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... Kin selection theory tenets that the eagerness to support one's relative is much higher than non-kin, and willingness to help is stronger toward younger kin than older ones. On the other hand, kindchenschema cuteness describes attractive facial features of children that elicit perceptions of cuteness and, when used as stimuli, release hormones such as dopamine, oxytocin, and prolactin, which stimulate social understanding and empathy (Abraham et al., 2014;Atzil et al., 2017). In parallel with kin selection, we expect sports marketing appeals with child images to trigger fans' feelings of kinship; in other words, to see their club as a family and thus behave altruistically. ...
... It is argued that the cute facial features of infants form a "Kindchenschema" (infant schema), a prime example of an "innate releasing mechanism" that unlocks instinctual behaviors (Kringelbach et al., 2016). Cute facial features of children, which elicit perceptions of cuteness and prolonged attention (Doebel et al., 2022) have a crucial role in complex emotional behaviors such as caregiving and facilitate social relations by releasing hormones such as dopamine, oxytocin, and prolactin (Abraham et al., 2014;Atzil et al., 2017) which stimulate social understanding, empathy, and compassion (Parsons et al., 2011;Sherman & Haidt, 2011). Since these hormones are associated with favorable judgments about others and social bonding, they could promote prosocial behaviors. ...
... Evaluating the explanations in kin selection theory (Garcia & Saad, 2008) and empirical findings in kindchenschema cuteness (Abraham et al., 2014;Atzil et al., 2017;Wang et al., 2017) together, we expect that sports marketing appeals with child images (vs. control) would increase fans' prosociality. ...
Article
This study explores the effect of child images in advertisements on financial support provided by team fans -including the intention to buy licensed club products- and reported aggression toward rival team fans. An online experiment was conducted on Turkey’s three largest rival club fans (Fenerbahçe, Galatasaray, and Bes¸iktas¸). Used visual materials were derived from Football (Study 1) and Basketball (Study 2). Fans (N = 496) exposed to the appeals with child images showed a higher intention to support their team financially and buy licensed club products; however, the stated aggression toward rival club fans did not differ. A follow-up experimental study (N = 132) was conducted on Fenerbahçe fans to retest this insignificant effect, in which fans’ state aggression is increased through a motivation video. It is concluded that this approach was only effective on aggression for the fans whose team identification was significantly higher. Findings are discussed within the kin selection theory and kindchenschema cuteness concept.
... While most women in the United States and Europe initiate breastfeeding, many mothers wean the infant within the first few postpartum weeks [27]. In 2019-2020, 83.9% of American women reported starting breastfeeding, yet only 25.8% continued breastfeeding exclusively after six months [28]. Shorter durations of breastfeeding were associated with psychological hardship, lower selfefficacy, and lower self-confidence [29]. ...
... Affect expressions and gaze are key behavioral features exchanged during social interactions [79,80]. Mothers attune their affective expressions to moments of mutual gaze [81,82] when infants are engaged in the interaction [83]. Consequently, with development, infants increase the duration of visual fixation on the mother's face and express more affect during an interaction [84]. ...
... Videos were captured in the families' homes or their local community center. Trained research personnel filmed the interaction based on our previous research [83,85,109,110]. Mothers were instructed to freely interact with their infants as usual, without any restrictions, specific toys, or guidelines; the videos did not include breastfeeding. ...
Article
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Simple Summary Breastfeeding is encouraged worldwide due to its nutritional and bonding benefits, but more attention needs to be given to the potential psychological challenges it poses to new mothers. This study investigated whether breastfeeding pain relates to mothers’ and infants’ bonding behavior. Seventy-one mothers with varying levels of breastfeeding pain were videotaped with their infants during face-to-face interactions. We found that mothers with severe breastfeeding pain express less affect and less infant-directed gaze during interactive moments of engagement and play than mothers with no or moderate pain. Infants of mothers experiencing pain also express less affect and more mother-directed gaze than those of mothers not experiencing pain. These findings suggest that maternal pain can interfere with the behaviors of both mothers and infants, potentially impacting development and bonding. Since the mother–infant dyad is a codependent allostatic unit, the allostatic challenges of one partner can influence both partners. Therefore, nutritional advances should be considered along with additional allostatic consequences of breastfeeding to ensure the well-being of both mothers and infants. Abstract Breast milk is considered the ideal infant nutrition, and medical organizations encourage breastfeeding worldwide. Moreover, breastfeeding is often perceived as a natural and spontaneous socio-biological process and one of the fundamental roles of new mothers. While breastfeeding is beneficial, little scientific consideration has been given to its potential psychological challenges. Here, we investigate the phenomenon of breastfeeding pain in mothers and its association with maternal and infant behavioral regulation. During the postpartum weeks, the mother–infant dyad can be considered one allostatic unit directed at infant regulation and development. We hypothesize that pain comprises an allostatic challenge for mothers and will thus impair the capacity for dyadic regulation. To test this, we recruited 71 mothers with varying levels of breastfeeding pain and videotaped them with their infants (2–35 weeks old) during spontaneous face-to-face interactions. We quantified the individual differences in dyadic regulation by behaviorally coding the second-by-second affective expressions for each mother and infant throughout their interactions. We tested the extent to which breastfeeding pain alters affect regulation during mother–infant interactions. We discovered that mothers with severe breastfeeding pain express less affective expressions and less infant-directed gaze during interactive moments of engagement and play than mothers with no or moderate pain. Moreover, infants of mothers experiencing pain during breastfeeding express less affective expressions and more mother-directed gaze while interacting with their mothers than infants of mothers who are not in pain. This demonstrates that the allostatic challenge of maternal pain interferes with the behavioral regulation of both mothers and infants. Since the mother–infant dyad is a codependent allostatic unit, the allostatic challenges of one partner can impact the dyad and thus potentially impact child development, bonding, and mother and infant well-being. The challenges of breastfeeding should be considered in addition to the nutritional advances.
... However, according to our observations, the GMV alteration follows a much more dynamic pattern, showing already from week 3 that the cerebellum, the thalamus and the dorsal striatum decrease in volume, with the surface of the orbital and lingual gyri becoming thinner. While the interpretation of these results may not be easy, potentially requiring further investigations, establishing a link to maternal behavior is possible given that maternal attachment is associated with the striatal dopamine function and the recruitment of a cortico-striatal-amygdala brain network, which augments the capability for attachment [30]. Furthermore, given that GMV change between 9 and 12 weeks postpartum was found to predict the extent of total maternal attachment (MPAS total score) as well as the absence of hostility, it seems that the maternal brain undergoes further maturation and specialization of the neural network subserving maternal behavior during the delayed postpartum period. ...
... These hormones are thought to induce neuroplasticity primarily by modulating dendritic spine and synapse density [32]. Thus, the considerable shift of estradiol and progesterone during pregnancy [1] is likely involved in the volumetric change in the amygdala during pregnancy and the postpartum period, with the medial and the dorsal amygdala networks [30], including the striatum, the anterior and posterior cingulate, the ventromedial prefrontal cortex and the insula [33] being key elements in human maternal bonding. Less hostile behavior toward the child has been found to be predicted by the volumetric change of the bilateral amygdala, the temporal pole, the right olfactory gyrus, the left anterior cingulate, the bilateral thalamus and the cerebellum, regions involved in socio-emotional processing and social cognition [34][35][36]. ...
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Pregnancy and the postpartum period are characterized by an increased neuroplasticity in the maternal brain. To explore the dynamics of postpartum changes in gray matter volume (GMV), magnetic resonance imaging was performed on 20 healthy postpartum women immediately after childbirth and at 3-week intervals for 12 postpartum weeks. The control group comprised 20 age-matched nulliparous women. The first 6 postpartum weeks (constituting the subacute postpartum period) are associated with decreasing progesterone levels and a massive restructuring in GMV, affecting the amygdala/hippocampus, the prefrontal/subgenual cortex, and the insula, which approach their sizes in nulliparous women only around weeks 3–6 postpartum. Based on the amygdala volume shortly after delivery, the maternal brain can be reliably distinguished from the nulliparous brain. Even 12 weeks after childbirth, the GMV in the dorsomedial prefrontal cortex, and the cortical thickness of the subgenual and lateral prefrontal cortices do not reach the pre-pregnancy levels. During this period, a volume decrease is seen in the cerebellum, the thalamus, and the dorsal striatum. A less hostile behavior toward the child at 6–12 weeks postpartum is predicted by the GMV change in the amygdala, the temporal pole, the olfactory gyrus, the anterior cingulate, the thalamus and the cerebellum in the same period. In summary, the restructuring of the maternal brain follows time-dependent trajectories. The fact that the volume changes persist at 12 weeks postpartum indicates that the maternal brain does not fully revert to pre-pregnancy physiology. Postpartum neuroplasticity suggests that these changes may be particularly significant in the regions important for parenting.
... Functional magnetic resonance imaging (fMRI) studies indicate that the mesolimbic DA system is activated as parents of both sexes view pictures of their own children but not pictures of other children, and this activation is enhanced by IN-OT [40][41][42]. In human mothers, behavioral synchrony between mother and infant is related to changes in endogenous DA and the functional connectivity of the NAc, MeA, and the medial (mPFC), together comprising the MeA network implicated in social functioning [43,44]. Additionally, plasma OT is correlated with the activation of the amygdala and NAc in mothers viewing their own infant [45]. ...
... This network was later expanded as the SDMN to include structures in the mesolimbic DA system involved in detecting and appraising the rewarding aspects of social situations [80]. Many of the structures of the SBN and SDMN have been implicated in human social function [43,46,81]. Cortical regions involved in emotional processing and decision-making, including the mPFC, ACC, and IC, have also been implicated in social function in rodents and humans alike [81][82][83]. ...
Article
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Simple Summary Being in love is a powerful emotional experience that is uniquely human; however, animal models of pair bonding provide insights into the neurobiological processes underlying love. Pair bonds are selective associations between two individuals (e.g., individuals in love) and can be studied in monogamous rodents such as prairie voles. Here, we examine pair bonds, from their evolutionary origins in mother–infant bonds, to the stages of bonding, comparing rodent and human literature. We discuss the neural circuits and neuromodulators driving bonding across species, with rodent studies providing insight into our human experiences of love. Abstract Love is a powerful emotional experience that is rooted in ancient neurobiological processes shared with other species that pair bond. Considerable insights have been gained into the neural mechanisms driving the evolutionary antecedents of love by studies in animal models of pair bonding, particularly in monogamous species such as prairie voles (Microtus ochrogaster). Here, we provide an overview of the roles of oxytocin, dopamine, and vasopressin in regulating neural circuits responsible for generating bonds in animals and humans alike. We begin with the evolutionary origins of bonding in mother–infant relationships and then examine the neurobiological underpinnings of each stage of bonding. Oxytocin and dopamine interact to link the neural representation of partner stimuli with the social reward of courtship and mating to create a nurturing bond between individuals. Vasopressin facilitates mate-guarding behaviors, potentially related to the human experience of jealousy. We further discuss the psychological and physiological stress following partner separation and their adaptive function, as well as evidence of the positive health outcomes associated with being pair-bonded based on both animal and human studies.
... This system's activation increases in response to viewing salient social stimuli (e.g., an infants' cry; Gregory et al., 2015). Moreover, individual differences in dopaminergic activation in the nucleus accumbens in response to one's own infant explain individual differences in maternal behavior (Atzil et al., 2017). ...
... Most studies have examined the oxytocin, vasopressin, and dopamine systems separately. However, these systems operate simultaneously, interact, and influence each other (Atzil et al., 2017;Chang et al., 2014). Thus, a full understanding of the relation between empathy and genetic variations in these systems would be accomplished only if they are investigated together (Machin & Dunbar, 2011). ...
Chapter
A range of empirical and theoretical perspectives on the relationship between biology and social cognition from infancy through childhood. Recent research on the developmental origins of the social mind supports the view that social cognition is present early in infancy and childhood in surprisingly sophisticated forms. Developmental psychologists have found ingenious ways to test the social abilities of infants and young children, and neuroscientists have begun to study the neurobiological mechanisms that implement and guide early social cognition. Their work suggests that, far from being unfinished adults, babies are exquisitely designed by evolution to capture relevant social information, learn, and explore their social environments. This volume offers a range of empirical and theoretical perspectives on the relationship between biology and social cognition from infancy through childhood. The contributors consider scientific advances in early social perception and cognition, including findings on the development of face processing and social perceptual biases; explore recent research on early infant competencies for language and theory of mind, including a developmental account of how young children become moral agents and the role of electrophysiology in identifying psychological processes that underpin social cognition; discuss the origins and development of prosocial behavior, reviewing evidence for a set of innate predispositions to be social, cooperative, and altruistic; examine how young children make social categories; and analyze atypical social cognition, including autism spectrum disorder and psychopathy. Contributors Lior Abramson, Renée Baillargeon, Pascal Belin, Frances Buttelmann, Melody Buyukozer Dawkins, Sofia Cardenas, Michael J. Crowley, Fabrice Damon, Jean Decety, Michelle de Haan, Ghislaine Dehaene-Lambertz, Xiao Pan Ding, Kristen A. Dunfield, Rachel D. Fine, Ana Fló, Jennifer R. Frey, Susan A. Gelman, Diane Goldenberg, Marie-Hélène Grosbras, Tobias Grossmann, Caitlin M. Hudac, Dora Kampis, Tara A. Karasewich, Ariel Knafo-Noam, Tehila Kogut, Ágnes Melinda Kovács, Valerie A. Kuhlmeier, Kang Lee, Narcis Marshall, Eamon McCrory, David Méary, Christos Panagiotopoulos, Olivier Pascalis, Markus Paulus, Kevin A. Pelphrey, Marcela Peña, Valerie F. Reyna, Marjorie Rhodes, Ruth Roberts, Hagit Sabato, Darby Saxbe, Virginia Slaughter, Jessica A. Sommerville, Maayan Stavans, Nikolaus Steinbeis, Fransisca Ting, Florina Uzefovsky, Essi Viding
... Infants' ages ranged between 2.5 and 48 weeks and mothers' ages ranged between 22 and 47 years. The sample size was determined with power analysis calculated for multivariate General Linear Model (GLM) using G*Power software 122 , given an effect size of 0.4, and power of 0.8 for comparing mother-infant interactions within two different cultures, relying on data from our previous research on mother-infant bonding behavior 123 , accordingly, all the statistical analyses that compare Jewish to Arab cultures control for variability explained by these variables, unless otherwise stated. The Institution Ethics Committee of the Hebrew University approved the study, the research protocol was performed in accordance with ethics guidelines, and all the mothers signed informed consent before participation and were remunerated for their participation. ...
... Capturing 2-min interactions optimizes the trade-off between the high validity of the data on one hand and minimal intrusion to post-partum women and their infants on the other hand. Accordingly, an experimental setup of 2-min mother-infant interactions is commonly applied 38,[123][124][125][128][129][130][131][132][133][134][135] . While short and thus susceptible to being affected by non-representative events, this data is rich in spontaneous interactive behaviors, providing a multi-dimensional matrix of 120 repeated data points per each behavioral variable for each dyadic partner. ...
Article
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Maternal care is considered a universal and even cross-species set of typical behaviors, which are necessary to determine the social development of children. In humans, most research on mother–infant bonding is based on Western cultures and conducted in European and American countries. Thus, it is still unknown which aspects of mother–infant behaviors are universal and which vary with culture. Here we test whether typical mother–infant behaviors of affect-communication and affect-regulation are equally represented during spontaneous interaction in Palestinian-Arab and Jewish cultures. 30 Palestinian-Arab and 43 Jewish mother–infant dyads were recruited and videotaped. Using AffectRegulation Coding System (ARCS), we behaviorally analyzed the second-by-second display of valence and arousal in each participant and calculated the dynamic patterns of affect co-regulation. The results show that Palestinian-Arab infants express more positive valence than Jewish infants and that Palestinian-Arab mothers express higher arousal compared to Jewish mothers. Moreover, we found culturally-distinct strategies to regulate the infant: increased arousal in Palestinian-Arab dyads and increased mutual affective match in Jewish dyads. Such cross-cultural differences in affect indicate that basic features of emotion that are often considered universal are differentially represented in different cultures. Affect communication and regulation patterns can be transmitted across generations in early-life socialization with caregivers.
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
Full-text available
Machine learning (ML) is a subarea of artificial intelligence which uses the induction approach to learn based on previous experiences and make conclusions about new inputs (Mitchell, Machine learning. McGraw Hill, 1997). In the last decades, the use of ML approaches to analyze neuroimaging data has attracted widening attention (Pereira et al., Neuroimage 45(1):S199–S209, 2009; Lemm et al., Neuroimage 56(2):387–399, 2011). Particularly interesting recent applications to affective and social neuroscience include affective state decoding, exploring potential biomarkers of neurological and psychiatric disorders, predicting treatment response, and developing real-time neurofeedback and brain-computer interface protocols. In this chapter, we review the bases of the most common neuroimaging techniques, the basic concepts of ML, and how it can be applied to neuroimaging data. We also describe some recent examples of applications of ML-based analysis of neuroimaging data to social and affective neuroscience issues. Finally, we discuss the main ethical aspects and future perspectives for these emerging approaches.
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
Full-text available
Several studies have demonstrated sex differences in empathy and social abilities. This chapter reviews studies on sex differences in the brain, with particular reference to how women and men process faces and facial expressions, social interactions, pain of others, infant faces, faces in things ( pareidolia ), living vs. non-living information, purposeful actions, biological motion, erotic vs. emotional information. Sex differences in oxytocin-based attachment response and emotional memory are also discussed. Overall, the female and male brains show some neuro-functional differences in several aspects of social cognition, with particular regard to emotional coding, face processing and response to baby schema that might be interpreted in the light of evolutionary psychobiology.
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
Full-text available
Embodiment has been discussed in the context of social, affective, and cognitive psychology, and also in the investigations of neuroscience in order to understand the relationship between biological mechanisms, body and cognitive, and social and affective processes. New theoretical models have been presented by researchers considering not only the sensory–motor interaction and the environment but also biological mechanisms regulating homeostasis and neural processes (Tsakiris M, Q J Exp Psychol 70(4):597–609, 2017). Historically, the body and the mind were comprehended as separate entities. The body was considered to function as a machine, responsible for providing sensory information to the mind and executing its commands. The mind, however, would process information in an isolated way, similar to a computer (Pecher D, Zwaan RA, Grounding cognition: the role of perception and action in memory, language, and thinking. Cambridge University Press, 2005). This mind and body perspective (Marmeleira J, Duarte Santos G, Percept Motor Skills 126, 2019; Marshall PJ, Child Dev Perspect 10(4):245–250, 2016), for many years, was the basis for studies in social and cognitive areas, in neuroscience, and clinical psychology.
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
Full-text available
Emotions modulate behavioral priorities via central and peripheral nervous systems. Understanding emotions from the perspective of specific neurotransmitter systems is critical, because of the central role of affect in multiple psychopathologies and the role of specific neuroreceptor systems as corresponding drug targets. Here, we provide an integrative overview of molecular imaging studies that have targeted the human emotion circuit at the level of specific neuroreceptors and transmitters. We focus specifically on opioid, dopamine, and serotonin systems, given their key role in modulating motivation and emotions, and discuss how they contribute to both healthy and pathological emotions.Keywords Molecular imaging Human emotions Dopamine systemSerotonin systemOpioid system
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
Full-text available
Emotions play a very important role in moral judgments. Hume argues that morality is determined by feelings that make us define whether an attitude is virtuous or criminal. This implies that an individual relies on their past experience to make a moral judgment, so that when the mind contemplates what it knows, it may trigger emotions such as disgust, contempt, affection, admiration, anger, shame, and guilt (Hume D. An enquiry concerning the principles of morals, 1777 ed. Sec. VI, Part I, para, 196, 1777). Thus, even so-called “basic” emotions can be considered as moral emotions. As Haidt (The moral emotions. In: Handbook of affective sciences, vol 11, 852–870, Oxford University Press, 2003) points out, all emotional processing that leads to the establishment and maintenance of the integrity of human social structures can be considered as moral emotion. Consequently, the construct of “morality” is often characterized by a summation of both emotion and cognitive elaboration (Haidt J. Psychol Rev, 108(4):814, 2001).
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
Chapter
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Social cognition refers to a wide range of cognitive abilities that allow individuals to understand themselves and others and also communicate in social interaction contexts (Adolphs, Curr Opin Neurobiol 11(2):231–239, 2001). According to Adolphs (Annu Rev Psychol 60(1):693–716, 2009), social cognition deals with psychological processes that allow us to make inferences about what is happening inside other people—their intentions, feelings, and thoughts. Although the term can be defined in many ways, it is clear that it must be safeguarded for the mental operations underlying social interactions. The most investigated cognitive processes of social cognition are emotion recognition and theory of mind (ToM), given that a whole range of socio-affective and interpersonal skills, such as empathy, derive from them (Mitchell RL, Phillips LH, Neuropsychologia, 70:1–10, 2015). Theory of mind is an intuitive ability to attribute thoughts and feelings to other people, and this ability usually matures in children in preschool age (Wellman HM, The child’s theory of mind. Bradford Books/MIT, 1990), whereas emotional recognition refers to an individual’s ability to identify others’ emotions and affective states, usually based on their facial or vocal expressions, it is a critical skill that develops early and supports the development of other social skills (Mitchell RL, Phillips LH, Neuropsychologia, 70:1–10, 2015).
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
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Transcranial brain stimulation (TBS) is a term that denotes different noninvasive techniques which aim to modulate brain cortical activity through an external source, usually an electric or magnetic one. Currently, there are several techniques categorized as TBS. However, two are more used for scientific research, the transcranial magnetic stimulation (TMS) and the transcranial direct current stimulation (tDCS), which stimulate brain areas with a high-intensity magnetic field or a weak electric current on the scalp, respectively. They represent an enormous contribution to behavioral, cognitive, and social neuroscience since they reveal how delimited brain cortical areas contribute to some behavior or cognition. They have also been proposed as a feasible tool in the clinical setting since they can modulate abnormal cognition or behavior due to brain activity modulation. This chapter will present the standard methods of transcranial stimulation, their contributions to social and affective neuroscience through a few main topics, and the studies that adopted those techniques, also summing their findings.
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
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No matter how hard you try—pinching different parts of your body, slapping your face, or moving restlessly in your seat—you cannot prevent your mind from occasionally escaping from the present experience as you enter into a mental navigation mode. Sometimes spontaneously, others deliberately, your mind may move to a different time—you may see yourself running an experiment inspired by the chapter you just finished reading or you may imagine yourself on a quantum leap into the future as you fantasize about the delivery of your Nobel Prize acceptance speech. Your mind may move to a distinct space, for example, as you replay last weekend’s party or anticipate a most desirable date, and may even venture into the mind of another (e.g., as you embody the mind of the author you are currently reading). Our minds can accomplish all this mental navigation in fractions of a second, allowing us to see ourselves or even impersonate different people across space and time. While teleportation and time travel may never be physically possible, our wandering minds are indeed very accomplished “time machines” (Suddendorf T, Corballis MC, Behav Brain Sci 30(3), 2007).
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
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This chapter provides information about facial electromyography (EMG) as a method of investigating emotions and affect, including examples of application and methods for analysis. This chapter begins with a short introduction to emotion theory followed by an operationalisation of facial emotional expressions as an underlying requirement for their study using facial EMG. This chapter ends by providing practical information on the use of facial EMG.KeywordsElectromyographyFacial EMGFacial emotional expressionsFacial muscles
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. ...
... There is less evidence for DA processing of other primary reward signals, but some studies suggest that romantic (Takahashi et al., 2015) and maternal attachmentrelated rewards (Atzil et al., 2017) are processed via the dopamine system in humans. However, these studies are difficult to interpret as the latter (Atzil et al., 2017) reported dopamine activations in regions where [11C]raclopride has either low or no specific binding and no sensitivity to even D2/D3R antagonist challenge (Svensson et al., 2019), and the former was based on an individual-differences approach (Takahashi et al., 2015) and failed to show significant main effects of DA release across the whole group of subjects. In addition, murine models typically show a decrease in DA release in response to social contact seeking (Manduca et al., 2014), rather than an increase as suggested by human PET data; this might however be due to cross-species differences in attachment circuits. ...
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The neurocognitive mechanism of emotion without conscious awareness has long been a subject of great interest (Pribram KH, Gill MM, Freud’s “project” re-assessed: preface to contemporary cognitive theory and neuropsychology. Basic Books, 1976). Several pervious psychological studies have used subliminal presentations of emotional facial expressions in the context of the affective priming paradigm to investigate unconscious emotional processing (e.g., Murphy ST, Zajonc RB, J Person Soc Psychol 64:723–739, 1993; for a review, see Eastwood JD, Smilek D, Conscious Cognit 14:565–584, 2005). In a typical application of this paradigm, a facial expression depicting a negative or positive emotion is flashed briefly as a prime, then an emotionally neutral target (e.g., an ideograph) is presented. Participants are asked to make emotion-related judgments about the target. The studies reported that evaluations of the target were negatively biased by unconscious negative primes, compared to positive primes. This effect has been interpreted as evidence that unconscious emotion can be elicited and that it affects the evaluation of unrelated targets.
... (Motivation ROI) (Fig. 2a). To test the robustness of our main findings, we also created (i) a structural ROI mask spanning the same regions and (ii) an extended ROI mask including an additional brain region (i.e. the subgenual ACC) known to receive strong projections from the hypothalamic and striatal regions, supporting human bonding and social cognition (Öngür et al., 1998;Atzil et al., 2017;Lockwood and Wittmann, 2018). In addition, as described in the result section, we defined two a posteriori ROIs using the terms "Empathy" (Empathy ROI) and "theory of mind" (Mentalizing ROI). ...
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Grandmothers enhances grandchild survival and maternal health through caregiving. Comparative evidence suggests that human grandmotherhood reflects a unique life history strategy promoting the inclusive fitness of post-reproductive females. Despite its evolutionary importance, the proximate neural mechanisms supporting grandmaternal caregiving remain unclear. This study uses functional magnetic resonance imaging (fMRI) and multivariate approaches to investigate how grandmaternal brains encode information about grandchildren and translate it into caregiving. Forty-seven grandmothers (Age = 59.1±7) completed an fMRI task viewing photos of a grandchild, the grandchild's parent, unfamiliar individuals, and non-human objects. Multi-voxel activation patterns associated with these stimuli were analyzed using representational similarity analysis, focusing on the hypothalamic and mesolimbic regions critical for mammalian parenting. Results reveal that grandchildren had most distinct multi-voxel pattern of activation within these regions, potentially reflecting the grandmothers’ motivational readiness to engage in grandmaternal caregiving. Indeed, greater neural dissimilarity between the grandchild and other social categories correlated with higher self-reported affection and supportive behaviors towards grandchildren, particularly in paternal grandmothers. Our findings provide novel insights into the mechanisms of grandmaternal caregiving that enhances inclusive fitness.
... Within the VTA, OT has been shown to enhance the activity of DA neurons and to stimulate DA release [44][45][46][47][48] . Studies in rodents [48][49][50] and humans 51,52 have shown that interactions between the OT and DA systems regulate maternal care, that if disrupted can derail mothering 48,52 . OT itself has also been implicated in depressive behavior including PPD [53][54][55] . ...
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Postpartum depression (PPD) affects up to 20% of new mothers and has adverse consequences for the well-being of both mother and child. Exposure to stress during pregnancy as well as dysregulation in the mesolimbic dopamine (DA) reward system and its upstream modulator oxytocin (OT) have been independently linked to PPD. However, no studies have directly examined DA or OT signaling in the postpartum brain after gestational stress. Here we employed a chronic variable stress procedure during pregnancy and evaluated behavioral measures of mood and reward along with assessments of DA and OT signaling in postpartum rats. Our results show that gestational stress induced postpartum depressive-like and anxiety-like behavior in addition to producing reward-related deficits including anhedonia, impaired maternal care, and reduced maternal motivation. Consistent with a hypodopaminergic state, histological analysis revealed reduced expression of tyrosine hydroxylase in the NAc shell and core as well as reduced expression of the dopamine transporter and dopamine D2 receptor in the NAc shell of postpartum females exposed to gestational stress. A reduction in accumbal DA content as determined by liquid chromatography-mass spectrometry was also observed in gestationally-stressed dams. Lastly, we assessed mRNA expression of OT and OT receptors (OTR) and found that gestational stress increased OT expression in the hypothalamus but reduced OTR expression in the postpartum ventral tegmental area (VTA), a target of hypothalamic OT neurons. In the VTA, a reduction in OT-immunoreactive fibers following gestational stress was also seen. Taken together, these data demonstrate that the DA and OT systems within the postpartum reward circuit are sensitive to gestational stress and suggest that mood and maternal disruptions in PPD may arise from dysfunctional oxytocinergic regulation of the dopaminergic reward system.
... Alone condition vs. anti-phase and in-phase Contextualizing these results is a challenge due to the wide variation in control tasks used across the literature. Nonetheless, our primary source for such comparisons is drawn from the Mogan et al. (2017) meta-analysis. Their control conditions fell under two categories: "socially coordinated" or "no action"; our Alone condition would fall neatly under their "no action" category, whereas our Anti-Phase condition would fall under the socially coordinated category. ...
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Purpose Music performance facilitates prosociality across many cultures and contexts. Interestingly, the relationship between prosociality and sensorimotor synchronization (SMS) has so far primarily been demonstrated in the context of in-phase synchrony with only a few mixed results for anti-phase coordination. In anti-phase coordination, participants move at the same rate, at opposite phases, which also requires high levels of coordination and attention. This case is particularly relevant for music and prosociality, as music regularly involves naturalistic anti-phase coordination. We thus tested whether anti-phase synchronization is as effective as in-phase synchronization at eliciting prosocial behavior. Methods Dyads ( N = 50 dyads) were randomly assigned to complete four trials of a drumming sensorimotor synchronization-continuation task (SCT) either alone, synchronously or in anti-phase. Before and after the drumming task, dyads completed a behavioral economics game involving trust. Additionally, a questionnaire about trust, cooperation, affect, and similarity was given after the drumming task. Results Cooperation rates in the stag-hunt game were near ceiling (~87%) across all conditions pre-SCT, with negligible change after the drumming task. Questionnaire items were analyzed using Bayesian probit mixed effects models to account for dyadic sampling and ordinal data, and to provide evidence in favor of the null hypothesis. Models provided moderate to extremely strong evidence that the anti-phase and in-phase coordination conditions rated their affect, trust, similarity, and cooperation more strongly than dyads in the alone condition (all BF 10 > 3). When only comparing the anti-phase and in-phase conditions, moderate evidence in favor of the null (i.e., that phase does not affect ratings) was found for all questions (all BF 10 < 0.3). Descriptions of the posterior, as well as leave-one-out cross validation (LOO) results, were in general accordance with the Bayes Factor results. Conclusion Evidence indicates anti-phase drumming coordination is as effective as in-phase in increasing perceived trust, cooperation, affect, and similarity. Future analyses will examine how other characteristics of the drumming coordination, such as the lag-1 autocorrelation and variability of the inter-tap interval time-series, relate to prosocial behavior and ratings of trust and cooperation.
... The MeA is closely linked to the accessory olfactory system in rodents and projects abundantly to the hypothalamus (162). These projections are important for multiple olfactory-guided social behaviors in rodents, including mating, aggression, and parenting (9,132,133,163). Although few studies exist on the MeA in humans (128), it likely receives direct projections from the human olfactory bulb (164), suggesting conservation of function across species. ...
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Reasoning about someone’s thoughts and intentions—i.e., forming a “theory of mind”—is a core aspect of social cognition and relies on association areas of the brain that have expanded disproportionately in the human lineage. We recently showed that these association zones comprise parallel distributed networks that, despite occupying adjacent and interdigitated regions, serve dissociable functions. One network is selectively recruited by social cognitive processes. What circuit properties differentiate these parallel networks? Here, we show that social cognitive association areas are intrinsically and selectively connected to anterior regions of the medial temporal lobe that are implicated in emotional learning and social behaviors, including the amygdala at or near the basolateral complex and medial nucleus. The results suggest that social cognitive functions emerge through coordinated activity between internal circuits of the amygdala and a broader distributed association network, and indicate the medial nucleus may play an important role in social cognition in humans.
... 17,47 However, very little research has compared mothers' and fathers' brain activity in the same study, making it challenging to understand how factors such as the time with the child, or pregnancy and lactation, may alter parental brain plasticity. 17,48,49 One study, comparing the brain response to a child in primary caregiver mothers and primary caregiver fathers, shows that primary caregiver mothers and primary caregiver fathers have similar activation levels in the amygdala, a central hub of the parental brain, in response to a video of them interacting with their infant versus a video of an unfamiliar parent interacting with an unfamiliar infant. 50 Furthermore, this amygdala activation is higher in primary caregivers than in secondary caregiver fathers. ...
... PET-MRI fusion imaging work has shown that specifically MOR but not D2R system is involved in empathy for pain (Karjalainen et al., 2017). However, in monkeys, access to social contact increases D2R levels and in humans social bonding may be mediated via D2R (Atzil et al., 2017;Morgan et al., 2002). Accordingly, the presently observed D2R downregulation might pertain atypical socioemotional functioning in psychopathy. ...
... The copyright holder for this preprint this version posted April 12, 2024. ; https://doi.org/10.1101/2024.04.09.588651 doi: bioRxiv preprint been recognized in earlier studies [69,71,82,83]. PET studies suggest a largely similar interaction between endogenous opioid and dopamine signaling in humans than observed in animals [36][37][38]. ...
Preprint
Opioid and dopamine receptor systems are implicated in the pathoetiology of autism, but in vivo human brain imaging evidence for their role remains elusive. Here, we investigated regional type 2 dopamine and mu-opioid receptor (D2R and MOR, respectively) availabilities and regional interactions between the two neuromodulatory systems associated with autism spectrum disorder (ASD). In vivo positron emission tomography (PET) with radioligands [11C]raclopride (D2R) and [11C]carfentanil (MOR) was carried out in 16 adult males with high functioning ASD and 19 age and sex matched controls. Regional group differences in D2R and MOR receptor availabilities were tested with linear mixed models and associations between regional receptor availabilities were examined with correlations. There were no group differences in whole-brain voxel-wise analysis of DR2 but ROI analysis presented a lower overall mean D2R availability in striatum of the ASD versus control group. Post hoc regional analysis revealed reduced D2R availability in nucleus accumbens of the ASD group. The whole-brain voxel-wise analysis of MOR revealed precuneal up-regulation in the ASD group, but there was no overall group difference in the ROI analysis for MOR. MOR down-regulation was observed in the hippocampi of the ASD group in a post hoc analysis. Regional correlations between D2R and MOR availabilities were weaker in the ASD group versus control group in the amygdala and nucleus accumbens. These alterations may translate to disrupted modulation of social motivation and reward in ASD.
... Parents are predisposed to respond emotionally to their infants and infants may detect even subtle emotional cues from parents (Atzil et al., 2017;Bornstein et al., 2012;Feldman, 2007;Murray et al., 2016). In fact, frank violations of parental still-face instructions (e.g., smiling) range from 1.8% to 5.8% of the duration of the still-face (Toda & Fogel, 1993;Tronick et al., 2005;Weinberg & Tronick, 1996). ...
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In the still‐face episode of the Face‐to‐Face/Still‐Face (FFSF), parents are asked to become unresponsive. However, infant–parent interaction may be irrepressible, and there is some evidence that interaction during the still‐face is associated with attachment outcome. To explore these questions, we independently coded the continuous affective valence (negative to positive) of seventy‐three 6‐month‐old infants (45 males; 36 Hispanic/Latinx; 38 White, 3 Black/African‐American, 2 Asian, 30 multiracial) and their parents (Mage = 36 years; 5 males; 30 Hispanic/Latinx; 65 White, 3 Black/African‐American, 2 Asian, 2 unknown) during the FFSF and assessed attachment at 15 months with the Strange Situation Procedure (n = 66). There was a mean positive correlation between moment‐to‐moment parent and infant affective valence, indicating synchronous affective interaction during the still‐face (d = 0.63). Higher levels of affect interaction during the still‐face episode were detected in infants later classified as disorganised compared to securely attached (d = 0.97). Findings underscore the importance of testing for still‐face interaction and suggest that this interaction may be an unappreciated predictor of infant attachment outcomes.
... The MeA receives direct and indirect input from the olfactory system, as well as DA neurons in the VTA. Dopaminergic signaling within the MeA mediates social reward and has even been implicated in human bonding (Atzil et al., 2017;Hu et al., 2021;Takahashi 2014). D1 receptor-expressing MeA neurons are activated by cat urine, and facilitating VTA dopaminergic transmission or activating D1 MeA GABAergic outputs to the BNST causes animals to display increased approach to a predator odor threat (McGregor et al., 2004;Miller et al., 2019;Vincenz et al., 2017). ...
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In rodents, exposure to predator odors such as cat urine acts as a severe stressor that engages innate defensive behaviors critical for survival in the wild. The neurotransmitters norepinephrine (NE) and dopamine (DA) modulate anxiety and predator odor responses, and we have shown previously that dopamine β-hydroxylase knockout (Dbh −/−), which reduces NE and increases DA in mouse noradrenergic neurons, disrupts innate behaviors in response to mild stressors such as novelty. We examined the consequences of Dbh knockout on responses to predator odor (bobcat urine) and compared them to Dbh-competent littermate controls. Over the first 10 min of predator odor exposure, controls exhibited robust defensive burying behavior, whereas Dbh −/− mice showed high levels of grooming. Defensive burying was potently suppressed in controls by drugs that reduce NE transmission, while excessive grooming in Dbh −/− mice was blocked by DA receptor antagonism. In response to a cotton square scented with a novel “neutral” odor (lavender), most control mice shredded the material, built a nest, and fell asleep within 90 min. Dbh −/− mice failed to shred the lavender-scented nestlet, but still fell asleep. In contrast, controls sustained high levels of arousal throughout the predator odor test and did not build nests, while Dbh −/− mice were asleep by the 90-min time point, often in shredded bobcat urine-soaked nesting material. Compared with controls exposed to predator odor, Dbh −/− mice demonstrated decreased c-fos induction in the anterior cingulate cortex, lateral septum, periaqueductal gray, and bed nucleus of the stria terminalis, but increased c-fos in the locus coeruleus and medial amygdala. These data indicate that relative ratios of central NE and DA signaling coordinate the type and valence of responses to predator odor.
... Neither can this association be explained by familiarity, as the familiarity difference between the owner and the control person is presumably similar in case of each dog, but at least does not differ systematically. Thus, it seems that the neural mechanisms mediating interspecific attachment to the owner are connected to the reward processing system in the dog brain, similarly to neural mechanisms for intraspecific attachment in other mammals ( Numan and Young, 2016 ), including humans ( Abrams et al., 2016 ;Atzil et al., 2017 ). An interesting indirect consequence of the present findings is that secondary auditory regions of the dog brain may play an important role in individual recognition of owners based on voice alone. ...
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Sine-wave f0 fMRI Dog Human a b s t r a c t Voice-sensitivity in the auditory cortex of a range of mammals has been proposed to be determined primarily by tuning to conspecific auditory stimuli, but recent human findings indicate a role for a more general tuning to voicelikeness. Vocal emotional valence, a central characteristic of vocalisations, has been linked to the same basic acoustic parameters across species. Comparative neuroimaging revealed that during voice perception, such acoustic parameters modulate emotional valence-sensitivity in auditory cortical regions in both family dogs and humans. To explore the role of voicelikeness in auditory emotional valence-sensitivity across species, here we constructed artificial emotional sounds in two sound categories: voice-like vs. sine-wave sounds, parametrically modulating two main acoustic parameters, f0 and call length. We hypothesised that if mammalian auditory systems are characterised by a general tuning to voicelikeness, voice-like sounds will be processed preferentially, and acoustic parameters for voice-like sounds will be processed differently than for sine-wave sounds-both in dogs and humans. We found cortical areas in both species that responded stronger to voice-like than to sine-wave stimuli, while there were no regions responding stronger to sine-wave sounds in either species. Additionally, we found that in bilateral primary and emotional valence-sensitive auditory regions of both species, the processing of voice-like and sine-wave sounds are modulated by f0 in opposite ways. These results reveal functional similarities between evolutionarily distant mammals for processing voicelikeness and its effect on processing basic acoustic cues of vocal emotions.
... A similar interpretation could be that connectedness between participants can increase as the time of FtF interaction increases. This is consistent with a study where bonding has been associated with the social reward system managed by vmPFC, amygdala and other regions of the medial frontal cortex (Atzil et al., 2017). Indeed, a study measuring bonding during FtF and CMC conditions reported that the FtF condition showed the highest rated level of bonding and text messaging the lowest (Sherman et al., 2013). ...
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Through evolution, humans have adapted their interactions to face-to-face communication, supported by a network of neural systems which facilitate the transmission and interpretation of social signals for successful communication. However, emerging methods of mediated communication are rapidly shifting our communication habits. For instance, text messaging has become a dominant mode of communication, surpassing face-to-face interaction in some contexts. This study explored differences in neural activation between face-to-face (FtF) and text-based computer-mediated communication (CMC) during a conversation between two communication partners. Seventeen pairs of participants were recruited and each pair undertook a ten-minute conversation in each communication condition. Functional near-infrared spectroscopy was utilized to measure neural activity in two relevant neural structures involved in social cognition: the ventro-medial prefrontal cortex (vmPFC), and the dorsomedial prefrontal cortex (dmPFC). The results indicated that text-based CMC generated more activity in dmPFC relative to FtF. No overall differences were observed between text-based CMC and FtF conditions in the vmPFC, although a linear trend existed across time showing increasing activation through the conversation in the FtF condition only. The results suggest there are differences in neural activations in key brain regions involved in social cognition and highlight the utility of brain imaging to reveal the way neural systems are engaged in different communication contexts. Understanding these differences in neural activation can provide insight into how the brain processes different communication methods and guide us to build tools that will aid text-based communication to provide more naturalistic experiences.
... In addition, CDC may have functions in addition to vocal learning, such as the promotion of long-term social bonds, as has been suggested for humans (3,49). Dopamine in the medial amygdala of humans has recently been found to mediate mother-infant behavioral synchronization and bonding (50). In juvenile zebra finches, social tutoring increased the activity of noradrenergic and dopaminergic midbrain neurons (26). ...
Article
Human caregivers interacting with children typically modify their speech in ways that promote attention, bonding, and language acquisition. Although this "motherese," or child-directed communication (CDC), occurs in a variety of human cultures, evidence among nonhuman species is very rare. We looked for its occurrence in a nonhuman mammalian species with long-term mother-offspring bonds that is capable of vocal production learning, the bottlenose dolphin (Tursiops truncatus). Dolphin signature whistles provide a unique opportunity to test for CDC in nonhuman animals, because we are able to quantify changes in the same vocalizations produced in the presence or absence of calves. We analyzed recordings made during brief catch-and-release events of wild bottlenose dolphins in waters near Sarasota Bay, Florida, United States, and found that females produced signature whistles with significantly higher maximum frequencies and wider frequency ranges when they were recorded with their own dependent calves vs. not with them. These differences align with the higher fundamental frequencies and wider pitch ranges seen in human CDC. Our results provide evidence in a nonhuman mammal for changes in the same vocalizations when produced in the presence vs. absence of offspring, and thus strongly support convergent evolution of motherese, or CDC, in bottlenose dolphins. CDC may function to enhance attention, bonding, and vocal learning in dolphin calves, as it does in human children. Our data add to the growing body of evidence that dolphins provide a powerful animal model for studying the evolution of vocal learning and language.
... For example, oxytocin exposure has been shown to increase activity in this reward network of the brain in men viewing photographs of their romantic partners (Scheele et al. 2013) and mothers viewing videos of their own (vs. other) infants (Atzil et al. 2017). Learning and habituation likely encourages reinforcement of in-character liking even under conditions of mere exposure (Montoya et al. 2017). ...
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This paper investigates the psychology of bleed-out, in which in-character dynamics spill over into out-of-character thoughts and feelings (Montola, 2011). We pair emerging neuroscience theory and research with classic models of emotion and motivation to examine the causes and consequences of this important larp phenomenon. Regarding positive bleed, hormones associated with trust and love may promote social bonding between players through shared in-character experiences (Kosfeld et al. 2005). Negative interpersonal dynamics could also develop, however, during antagonistic character interaction via “neural alarm bells” -- increased activation in brain areas associated with social rejection (Eisenberger, Leiberman, and Williams 2003). Such neural activity could in turn set off defensive aggression or social withdrawal (Twenge et al. 2001), behaviors that could bleed over into out-of-game interactions. The impact of these and other neuropsychological reactions on players’ behavior may be determined by the degree to which the line between self and character becomes blurred during play. According to Lankoski and Järvelä (2012), however, such blurring is a baked-in feature of human embodied cognition. Therefore, we propose that compartmentalizing “in-character” reactions requires immense self-regulatory control – a limited resource which is known to be depleted through many activities common to larp, e.g., effortful decision making and self-presentation (Vohs, Baumeister, and Ciarocco 2005; Vohs et al. 2014). Connecting self-regulatory resource models with bleed in this way is especially important since negative bleed-out can be a source of conflict in player communities (Bowman 2013). As such, we offer proactive solutions for those players or designers who wish to tailor a particular larp experience in order to avoid bleed-out, building on pre-existing best practices: informed consent, safe-spaces, and debriefing (Burns 2014; Atwater 2016; Brown 2016; Bowman, Brown, Atwater, and Rowland 2017).
... Increased serotonin reduces oxytocin levels, indirectly producing OT deficits [36]. A dysfunctional midbrain dopaminergic system [37,38,39], mutations in dopamine transporter protein [40], and perturbations in dopamine signaling [37,41,42] contribute to central executive deficits observed in ASD [43]. Endorphins (endogenous opioid system) play a key Chauhan N MedPress Publications LLC role in enhancing the rewarding properties of dopamine and therefore observed deficits of endorphin in ASD indirectly reduce dopamine, adding to the effects of dopamine deficiency in ASD [32]. ...
Article
Autism spectrum disorder (ASD) is a global health crisis. There is an increasing prevalence of ASD not only in US but throughout the world mainly affecting children and adolescents. ASD exhibits compromised quality of life characterized by persistent deficits in two core areas of functioning including social communication and interaction, and restricted/repetitive patterns of motor activities.
Article
This study explores the diagnostic value of dopamine system imaging characteristics in children with autism spectrum disorder. Functional magnetic resonance data from 551 children in the Autism Brain Imaging Data Exchange database were analyzed, focusing on six dopamine-related brain regions as regions of interest. Functional connectivity between these ROIs and across the whole brain was assessed. Machine learning techniques then evaluated the ability of the dopamine system’s imaging features to predict autism spectrum disorder. Functional connectivity was significantly higher in autism spectrum disorder children between the ventral tegmental area and substantia nigra, prefrontal cortex, nucleus accumbens, and between the substantia nigra and hypothalamus compared to typically developing children. Additionally, clustering methods identified two autism spectrum disorder subtypes, achieving over 0.8 accuracy. Subtype 1 showed higher stereotyped behavior scores than subtype 2 in both genders, with subtype-specific functional connectivity differences between male and female autism spectrum disorder groups. These findings suggest that abnormal functional connectivity in the dopamine system serves as a diagnostic biomarker for autism spectrum disorder and can support clinical decision-making and personalized treatment optimization.
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What does it mean to become attached? Three longitudinal studies established the empirical basis for the existing four‐phase model of attachment formation, a model that has remained unmodified and unexamined for over half a century. In this paper, I revisit the research questions, methods, and findings from the seminal studies to reevaluate the current model. The evidence indicates two distinct definitions of attachment onset. In the first two phases of the model, becoming attached is defined by changes in within‐subject behaviors leading to the selection of a discriminated figure. Defined this way, attachment onset is analogous to how bond formation is currently defined in other mammals and how imprinting is understood in birds. In contrast, the third and fourth phases of the model define attachment onset by forming a goal‐corrected relationship. This second definition is human‐centric and relies on secure base behavior as the signature criterion, the same criteria used to classify secure and insecure patterns of attachment. I argue for a narrower definition of attachment by removing goal‐corrected behavior as a criterion and focusing on the normative process of selection. In addition, I integrate contemporary work on pair bonding in humans and other animals to propose new avenues for conceptualizing and studying attachment formation in infancy and beyond in filial and sexual bonds.
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We aim to provide an overview of technical and clinical unmet needs in deep learning (DL) applications for quantitative and qualitative PET in PET/MR, with a focus on attenuation correction, image enhancement, motion correction, kinetic modeling, and simulated data generation. (1) DL-based attenuation correction (DLAC) remains an area of limited exploration for pediatric whole-body PET/MR and lung-specific DLAC due to data shortages and technical limitations. (2) DL-based image enhancement approximating MR-guided regularized reconstruction with a high-resolution MR prior has shown promise in enhancing PET image quality. However, its clinical value has not been thoroughly evaluated across various radiotracers, and applications outside the head may pose challenges due to motion artifacts. (3) Robust training for DL-based motion correction requires pairs of motion-corrupted and motion-corrected PET/MR data. However, these pairs are rare. (4) DL-based approaches can address the limitations of dynamic PET, such as long scan durations that may cause patient discomfort and motion, providing new research opportunities. (5) Monte-Carlo simulations using anthropomorphic digital phantoms can provide extensive datasets to address the shortage of clinical data. This summary of technical/clinical challenges and potential solutions may provide research opportunities for the research community towards the clinical translation of DL solutions.
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Mammalian parental care is highly mother-biased, prompting researchers to presume its connection to female reproductive behavior and physiology, not male. However, recent findings in neurobiological studies suggest the opposite. Considering the evolutionary path of mammalian parental care, the ancestral form of vertebrate parental care appears to be male-biased as in living teleosts (bony fish), and originated from egg guarding as an extension of territorial behavior. Phylogenetic analyses suggest that in basal tetrapods, the harsh reproductive environments have facilitated terrestrial adaptation and extensive parental investment in females, and salamander-like basal amniotes exhibited extended egg retention in female bodies. Molecular and fossil evidence indicates that synapsids that have later evolved into mammals have already performed extensive maternal care including egg/offspring hydration in the Carboniferous period. Then the nocturnal adaptation in Jurassic mammaliaforms promoted endothermy and prolonged maternal care for thermal control and lactation. This situation may have added nutritional gate control to the offspring care circuit to balance parental provisioning with maternal homeostatic needs. Combining these paleontological, comparative ecological, and neuromolecular findings, we propose that the mammalian parenting circuit may be derived from MPOA neurons controlling reproductive behaviors during the terrestrial adaptation in anamniotes, either by divergent or parallel evolution. Next, we discuss another long-postulated hypothesis that complex affiliative sociality among adults, including group living, cooperative infant care, empathy, and altruism, may have emerged primarily for extended support of the offspring growth, utilizing the established maternal care circuit in mammals. These evolution-informed working hypotheses may also help dissect the neural basis of the complex cognitive functions in mammals.
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Parental responsiveness and synchronization during early face-to-face interactions between mother and infant have been theorized to affect a broad spectrum of positive developmental outcomes in social and cognitive infant growth and to facilitate the development of a sense of self in the baby. Here we show that being imitated can significantly affect the behavior of nursery-reared infant monkeys, which are at an increased risk for developing aberrant social behaviors. Infants look longer and lipsmack more at an experimenter both during imitation and after being imitated. These results demonstrate that from early in life imitation might be used as a privileged form of communication by adults to enhance infants' visual engagement and their social communication. Imitation may therefore be useful to counteract the negative effects of early social adversities.
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Significance Oxytocin promotes positive social behaviors in several species and therefore may be a therapeutic tool for neurodevelopmental disorders. It remains untested, however, whether oxytocin may affect infants, and whether effects may vary depending on infants’ social skills or interest. To test these predictions, we administered nebulized oxytocin to rhesus macaque newborns. Macaques, like humans, engage in complex face-to-face mother–infant interactions. Oxytocin increased infants’ affiliative communicative gestures and decreased salivary cortisol, and higher oxytocin levels were associated with greater social interest. Infants with stronger imitative skills were most positively influenced by oxytocin, suggesting that oxytocin sensitivity may underlie early social motivation. These results suggest that oxytocin may be a promising early intervention for infants at risk for abnormal social functions.
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Eight low-functioning and non-verbal children with autism were presented with a modified version of the ‘still face’ paradigm (still face/imitative interaction/still face) performed by a stranger. The children’s reactions illustrate the development of expectancies concerning human social behaviour. While they ignored the stranger and did not show any concern about her odd behaviour during the first still episode, they all focused on the adult during the second still episode. In this episode, they exhibited a mixed social pattern of positive overtures and negative emotional expressions which resembles the still face effect found in normally developing infants. These findings suggest that low-functioning children with autism are able to integrate their previous experience with a partner and detect social contingency, but that they are not able to form a generalized expectancy for social contingency in human beings with whom they have not yet had contact. This may explain why they generally ignore strangers.
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Using resting-state functional magnetic resonance imaging data from two independent samples of healthy adults, we parsed the amygdala's intrinsic connectivity into three partially distinct large-scale networks that strongly resemble the known anatomical organization of amygdala connectivity in rodents and monkeys. Moreover, in a third independent sample, we discovered that people who fostered and maintained larger and more complex social networks not only had larger amygdala volumes, but also amygdalae with stronger intrinsic connectivity within two of these networks: one putatively subserving perceptual abilities and one subserving affiliative behaviors. Our findings were anatomically specific to amygdalar circuitry in that individual differences in social network size and complexity could not be explained by the strength of intrinsic connectivity between nodes within two networks that do not typically involve the amygdala (i.e., the mentalizing and mirror networks), and were behaviorally specific in that amygdala connectivity did not correlate with other self-report measures of sociality.
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Research on the neurobiology of parenting has defined biobehavioral synchrony, the coordination of biological and behavioral responses between parent and child, as a central process underpinning mammalian bond formation. Bi-parental rearing, typically observed in monogamous species, is similarly thought to draw on mechanisms of mother-father synchrony. We examined synchrony in mothers' and fathers' brain response to ecologically valid infant cues. Thirty mothers and fathers, comprising 15 couples parenting 4- to 6-month-old infants, were visited at home, and infant play was videotaped. Parents then underwent functional magnetic resonance imaging scanning while observing own-infant compared with standard-infant videos. Coordination in brain response between mothers and fathers was assessed using a voxel-by-voxel algorithm, and gender-specific activations were also tested. Plasma oxytocin and arginine vasopressin, neuropeptides implicated in female and male bonding, were examined as correlates. Online coordination in maternal and paternal brain activations emerged in social-cognitive networks implicated in empathy and social cognition. Mothers showed higher amygdala activations and correlations between amygdala response and oxytocin. Fathers showed greater activations in social-cognitive circuits, which correlated with vasopressin. Parents coordinate online activity in social-cognitive networks that support intuitive understanding of infant signals and planning of adequate caregiving, whereas motivational-limbic activations may be gender specific. Although preliminary, these findings demonstrate synchrony in the brain response of two individuals within an attachment relationship, and may suggest that human attachment develops within the matrix of biological attunement and brain-to-brain synchrony between attachment partners.
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Building on animal research, the past decade has witnessed a surge of interest in the effects of oxytocin on social cognition and prosocial behavior in humans. This work has generated considerable excitement about identifying the neurochemical underpinnings of sociality in humans, and discovering compounds to treat social functioning deficits. Inspection of the literature, however, reveals that the effects of oxytocin in the social domain are often weak and/or inconsistent. We propose that this literature can be informed by an interactionist approach in which the effects of oxytocin are constrained by features of situations and/or individuals. We show how this approach can improve understanding of extant research, suggest novel mechanisms through which oxytocin might operate, and refine predictions about oxytocin pharmacotherapy.
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Social psychological and developmental research revealed that imitation serves a fundamental social function. It has been shown that human beings have the tendency to automatically mirror the behavior of others-the so-called chameleon effect. Furthermore, it has been demonstrated that being imitated leads to positive feelings toward the imitator. But why do we feel more positive about someone who imitates us? In the current fMRI study we aimed at exploring the neural correlates of the positive consequences of being imitated by means of an observation paradigm. Our results indicate that being imitated compared to not being imitated activates brain areas that have been associated with emotion and reward processing, namely medial orbitofrontal cortex/ventromedial prefrontal cortex (mOFC/vmPFC, GLM whole-brain contrast). Moreover mOFC/vmPFC shows higher effective connectivity with striatum and mid-posterior insula during being imitated compared to not being imitated.
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There is good evidence that interference with the mesolimbic dopamine (DA) system results in impaired maternal responding in postpartum female rats. However, whether activation of the mesolimbic DA system is capable of promoting maternal behavior has not been investigated. This study examined whether increasing DA activity in various brain regions of pregnancy-terminated, naive female rats would stimulate the onset of maternal behavior. Experiments 1 and 2 examined the effects of microinjection of various doses (0, 0.2, or 0.5 microg/0.5 microl/side) of a D1 DA receptor agonist, SKF 38393, or a D2 DA receptor agonist, quinpirole, into the nucleus accumbens (NA) on latency to show full maternal behavior, and Experiment 3 determined the effects of SKF 38393 injection into a control site. Finally, because the medial preoptic area (MPOA) is also important for maternal behavior, receives DA input, and expresses DA receptors, the authors examined whether microinjection of SKF 38393 into MPOA was capable of stimulating the onset of maternal behavior. Results indicated that microinjection of SKF 38393 into either the NA or the MPOA facilitates maternal responding in pregnancy-terminated rats.
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In the last several decades, sophisticated experimental techniques have been used to elucidate the neurobiology of the oxytocin and vasopressin systems in rodents. Using a suite of methodologies, including electrophysiology, site-specific selective pharmacology, receptor autoradiography, in vivo microdialysis, and genetic and optogenetic manipulations, we have gained unprecedented knowledge about how these neuropeptides engage neural circuits to regulate behavior, particularly social behavior. Based on this foundation of information from rodent studies, we have started generating new hypotheses and frameworks about how the oxytocin and vasopressin systems could be acting in humans to influence social cognition. However, despite the recent inundation of publications using intranasal oxytocin in humans, we still know very little about the neurophysiology of the oxytocin system in primates more broadly. Furthermore, the design and analysis of these human studies have remained largely uninformed of the potential neurobiological mechanisms underlying their findings. While the methods available to study the oxytocin and vasopressin systems in humans are incredibly limited due to practical and ethical considerations, there is great potential to fill the gaps in our knowledge by developing better nonhuman primate models of social functioning. Behavioral pharmacology and receptor autoradiography have been used to study the oxytocin and vasopressin systems in nonhuman primates, and there is now great potential to broaden our understanding of the neurobiology of these systems. In this review, we discuss comparative findings in receptor distributions in rodents and primates, with perspectives on the functionality of conserved regions of expression in these distinct mammalian clades. We also identify specific ways that established technologies can be used to answer basic research questions in primates. Finally, we highlight areas of future research in nonhuman primates that are experimentally poised to yield critical insights into the anatomy, physiology, and behavioral effects of the oxytocin system, given its remarkable translational potential. This article is protected by copyright. All rights reserved.
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Mother-infant bonding is a characteristic of virtually all mammals. The maternal neural system may have provided the scaffold upon which other types of social bonds in mammals have been built. For example, most mammals exhibit a polygamous mating system, but monogamy and pair bonding between mating partners occurs in ~5% of mammalian species. In mammals, it is plausible that the neural mechanisms that promote mother-infant bonding have been modified by natural selection to establish the capacity to develop a selective bond with a mate during the evolution of monogamous mating strategies. Here we compare the details of the neural mechanisms that promote mother-infant bonding in rats and other mammals with those that underpin pair bond formation in the monogamous prairie vole. Although details remain to be resolved, remarkable similarities and a few differences between the mechanisms underlying these two types of bond formation are revealed. For example, amygdala and nucleus accumbens-ventral pallidum (NA-VP) circuits are involved in both types of bond formation, and dopamine and oxytocin action within NA appears to promote the synaptic plasticity that allows either infant or mating partner stimuli to persistently activate NA-VP attraction circuits, leading to an enduring social attraction and bonding. Further, although the medial preoptic area is essential for maternal behavior, its role in pair bonding remains to be determined. Our review concludes by examining the broader implications of this comparative analysis, and evidence is provided that the maternal care system may have also provided the basic neural foundation for other types of strong social relationships, beyond pair bonding, in mammals, including humans. Copyright © 2015. Published by Elsevier Inc.
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Previous research suggests that being imitated by an adult increases the social behaviors of children with an autism spectrum disorder (ASD). In the current study, we examined whether familiarity with the imitating social partner modulates this effect. Ten children with ASD and their mothers participated. The children's social behaviors were observed prior to and following a 3-min period in which an adult social partner imitated everything they did. In one condition the partner was the child's mother, and in the other condition the partner was an unfamiliar experimenter. The results revealed significant increases in distal social behaviors (gazes toward the adult, vocalizing) following imitation by both partners. There was a significantly greater increase in proximal social behaviors (including approach, being physically close, and touching) and a greater decrease in playing alone when the imitator was the child's mother as opposed to the experimenter. The findings suggest that the experience of being imitated creates an atmosphere of mutuality and rapport between children with ASD and their social partners, which increases their sociability even in interactions with already familiar adults. Autism Res 2014, ●●: ●●-●●. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.
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We present a technique for automatically assigning a neuroanatomical label to each voxel in an MRI volume based on probabilistic information automatically estimated from a manually labeled training set. In contrast to existing segmentation procedures that only label a small number of tissue classes, the current method assigns one of 37 labels to each voxel, including left and right caudate, putamen, pallidum, thalamus, lateral ventricles, hippocampus, and amygdala. The classification technique employs a registration procedure that is robust to anatomical variability, including the ventricular enlargement typically associated with neurological diseases and aging. The technique is shown to be comparable in accuracy to manual labeling, and of sufficient sensitivity to robustly detect changes in the volume of noncortical structures that presage the onset of probable Alzheimer's disease.
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Depressed mothers show negatively biased responses to their infants' emotional bids, perhaps due to faulty processing of infant cues. This study is the first to examine depression-related differences in mothers' neural response to their own infant's emotion faces, considering both effects of perinatal depression history and current depressive symptoms. Primiparous mothers (n = 22), half of whom had a history of major depressive episodes (with one episode occurring during pregnancy and/or postpartum), were exposed to images of their own and unfamiliar infants' joy and distress faces during functional neuroimaging. Group differences (depression vs. no-depression) and continuous effects of current depressive symptoms were tested in relation to neural response to own infant emotion faces. Compared to mothers with no psychiatric diagnoses, those with depression showed blunted responses to their own infant's distress faces in the dorsal anterior cingulate cortex. Mothers with higher levels of current symptomatology showed reduced responses to their own infant's joy faces in the orbitofrontal cortex and insula. Current symptomatology also predicted lower responses to own infant joy-distress in left-sided prefrontal and insula/striatal regions. These deficits in self-regulatory and motivational response circuits may help explain parenting difficulties in depressed mothers.
Article
Abstract— The speech of depressed and well mothers during play with their infants at two months was compared on dimensions of structure and semantics. No differences between maternal groups were found on measures of complexity and syntax. However, the speech of depressed women expressed more negative affect, was less focused on infant experience, and tended to show less acknowledgement of infant agency. Speech style of depressed women also varied according to infant gender. Regression analyses indicated that the quality of maternal communication with the infant, and particularly the focus of speech, mediated the association between depression and infant cognitive development in the first 18 months.
Article
To understand the neural basis of human speech control, extensive research has been done using a variety of methodologies in a range of experimental models. Nevertheless, several critical questions about learned vocal motor control still remain open. One of them is the mechanism(s) by which neurotransmitters, such as dopamine, modulate speech and song production. In this review, we bring together the two fields of investigations of dopamine action on voice control in humans and songbirds, who share similar behavioral and neural mechanisms for speech and song production. While human studies investigating the role of dopamine in speech control are limited to reports in neurological patients, research on dopaminergic modulation of bird song control has recently expanded our views on how this system might be organized. We discuss the parallels between bird song and human speech from the perspective of dopaminergic control as well as outline important differences between these species.
Article
The mother-infant bond provides the foundation for the infant's future mental health and adaptation and depends on the provision of species-typical maternal behaviors that are supported by neuroendocrine and motivation-affective neural systems. Animal research has demonstrated that natural variations in patterns of maternal care chart discrete profiles of maternal brain-behavior relationships that uniquely shape the infant's lifetime capacities for stress regulation and social affiliation. Such patterns of maternal care are mediated by the neuropeptide Oxytocin and by stress- and reward-related neural systems. Human studies have similarly shown that maternal synchrony--the coordination of maternal behavior with infant signals--and intrusiveness--the excessive expression of maternal behavior--describe distinct and stable maternal styles that bear long-term consequences for infant well-being. To integrate brain, hormones, and behavior in the study of maternal-infant bonding, we examined the fMRI responses of synchronous vs intrusive mothers to dynamic, ecologically valid infant videos and their correlations with plasma Oxytocin. In all, 23 mothers were videotaped at home interacting with their infants and plasma OT assayed. Sessions were micro-coded for synchrony and intrusiveness. Mothers were scanned while observing several own and standard infant-related vignettes. Synchronous mothers showed greater activations in the left nucleus accumbens (NAcc) and intrusive mothers exhibited higher activations in the right amygdala. Functional connectivity analysis revealed that among synchronous mothers, left NAcc and right amygdala were functionally correlated with emotion modulation, theory-of-mind, and empathy networks. Among intrusive mothers, left NAcc and right amygdala were functionally correlated with pro-action areas. Sorting points into neighborhood (SPIN) analysis demonstrated that in the synchronous group, left NAcc and right amygdala activations showed clearer organization across time, whereas among intrusive mothers, activations of these nuclei exhibited greater cross-time disorganization. Correlations between Oxytocin with left NAcc and right amygdala activations were found only in the synchronous group. Well-adapted parenting appears to be underlay by reward-related motivational mechanisms, temporal organization, and affiliation hormones, whereas anxious parenting is likely mediated by stress-related mechanisms and greater neural disorganization. Assessing the integration of motivation and social networks into unified neural activity that reflects variations in patterns of parental care may prove useful for the study of optimal vs high-risk parenting.
Article
Little is known about neural mechanisms of postpartum depression (PPD). Previous research notes ventral striatal activity and dopamine release increases with maternal attachment but decreases in major depressive disorder. This study tests the hypothesis that striatal response to reward is altered in PPD. Subjects underwent functional magnetic resonance imaging blood oxygenation level-dependent acquisition during a fast event-related card-guessing, monetary reward task. Time series data from an independent sample of 10 healthy mothers were used to establish the ventral striatal region of interest (ROI). Repeated-measures analysis of variance of time series data in the established ROI was then conducted for a discrete group of healthy (n = 12) and depressed, unmedicated mothers (n = 12). Data from the independent sample of 10 healthy mothers established an ROI in the left ventral striatum (-13, 12, -4, 477 mm(3)), with cluster significance p < .01, corrected. There was a significant quadratic interaction of time × group [F(1,22) = 5.22, p = .032] in this ROI in the healthy (n = 12) and depressed mothers (n = 12). This effect represents a nonlinear attenuation of ventral striatal response with time that was greater in depressed than healthy mothers. Rapid attenuation of ventral striatal response to reward receipt in postpartum depression might represent an important neural mechanism of postpartum depression. Additional study with infant stimuli and in relationship to mother-infant behavior is needed.
Article
Social and communication impairments are core deficits and prognostic indicators of autism. We evaluated the impact of supplementing a comprehensive intervention with a curriculum targeting socially synchronous behavior on social outcomes of toddlers with autism spectrum disorders (ASD). Fifty toddlers with ASD, ages 21 to 33 months, were randomized to one of two six-month interventions: Interpersonal Synchrony or Non-Interpersonal Synchrony. The interventions provided identical intensity (10 hours per week in classroom), student-to-teacher ratio, schedule, home-based parent training (1.5 hours per month), parent education (38 hours), and instructional strategies, except the Interpersonal Synchrony condition provided a supplementary curriculum targeting socially engaged imitation, joint attention, and affect sharing; measures of these were primary outcomes. Assessments were conducted pre-intervention, immediately post-intervention, and, to assess maintenance, at six-month follow-up. Random effects models were used to examine differences between groups over time. Secondary analyses examined gains in expressive language and nonverbal cognition, and time effects during the intervention and follow-up periods. A significant treatment effect was found for socially engaged imitation (p = .02), with more than doubling (17% to 42%) of imitated acts paired with eye contact in the Interpersonal Synchrony group after the intervention. This skill was generalized to unfamiliar contexts and maintained through follow-up. Similar gains were observed for initiation of joint attention and shared positive affect, but between-group differences did not reach statistical significance. A significant time effect was found for all outcomes (p < .001); greatest change occurred during the intervention period, particularly in the Interpersonal Synchrony group. This is the first ASD randomized trial involving toddlers to identify an active ingredient for enhancing socially engaged imitation. Adding social engagement targets to intervention improves short-term outcome at no additional cost to the intervention. The social, language, and cognitive gains in our participants provide evidence for plasticity of these developmental systems in toddlers with ASD. http://www.clinicaltrials.gov/ct2/show/NCT00106210?term = landa&rank = 3.
Article
Default mode network (DMN) is characterized by a deactivation of several cortical areas (including medial prefrontal cortex and posterior cingulate cortex) during goal-directed experimental tasks. Few findings are reported on DMN and the involvement of dopaminergic medication on this network in Parkinson's disease (PD). To evaluate the effect of levodopa on DMN deactivation, we conducted a randomized, crossover, placebo-controlled experiment consisting of two fMRI assessments in fourteen non-demented, non-depressed PD patients compared to thirteen healthy volunteers. They received either acute doses of levodopa or placebo in two fMRI sessions. Brain deactivation was evaluated during a facial emotion recognition task. While the control subjects showed a classical brain deactivation pattern during the emotional task, the PD patients taking placebo only deactivated the ventral medial prefrontal cortex. Patients failed to deactivate the posterior midline and lateral parts of DMN network. After levodopa administration, this network was restored conjointly with the improvement of motor dysfunction in PD patients. The levodopa effect on DMN is probably the consequence of a beneficial dopamine (DA) medication effect which leads to a fine tuning of the dopamine level in the motor part of striatum, resulting to a global improvement of physical state of PD patients and consequently an increased attentional resource to external stimuli. The absence of medial prefrontal deactivation impairment may suggest a preserved mesocortical DA system in these patients.
Article
Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli.
Article
The distribution volume ratio (DVR), which is a linear function of receptor availability, is widely used as a model parameter in imaging studies. The DVR corresponds to the ratio of the DV of a receptor-containing region to a nonreceptor region and generally requires the measurement of an arterial input function. Here we propose a graphical method for determining the DVR that does not require blood sampling. This method uses data from a nonreceptor region with an average tissue-to-plasma efflux constant k2 to approximate the plasma integral. Data from positron emission tomography studies with [11C]raclopride (n = 20) and [11C]d-threo-methylphenidate ([11C]dMP) (n = 8) in which plasma data were taken and used to compare results from two graphical methods, one that uses plasma data and one that does not. k2 was 0.163 and 0.051 min-1 for [11C]raclopride and [11C]dMP, respectively. Results from both methods were very similar, and the average percentage difference between the methods was -0.11% for [11C]raclopride and 0.46% for [11C]dMP for DVR of basal ganglia (BG) to cerebellum (CB). Good agreement between the two methods was also achieved for DVR images created by both methods. This technique provides an alternative method of analysis not requiring blood sampling that gives equivalent results for the two ligands studied. It requires initial studies with blood sampling to determine the average kinetic constant and to test applicability. In some cases, it may be possible to neglect the k2 term if the BG/CB ratio becomes reasonably constant for a sufficiently long period of time over the course of the experiment.
Article
Schultz, Wolfram. Predictive reward signal of dopamine neurons. is called rewards, which elicit and reinforce approach behav-J. Neurophysiol. 80: 1–27, 1998. The effects of lesions, receptor ior. The functions of rewards were developed further during blocking, electrical self-stimulation, and drugs of abuse suggest the evolution of higher mammals to support more sophistithat midbrain dopamine systems are involved in processing reward cated forms of individual and social behavior. Thus biologiinformation and learning approach behavior. Most dopamine neucal and cognitive needs define the nature of rewards, and rons show phasic activations after primary liquid and food rewards and conditioned, reward-predicting visual and auditory stimuli. the availability of rewards determines some of the basic They show biphasic, activation-depression responses after stimuli parameters of the subject’s life conditions. that resemble reward-predicting stimuli or are novel or particularly Rewards come in various physical forms, are highly variable salient. However, only few phasic activations follow aversive stim-in time and depend on the particular environment of the subject. uli. Thus dopamine neurons label environmental stimuli with appe- Despite their importance, rewards do not influence the brain titive value, predict and detect rewards and signal alerting and motivating events. By failing to discriminate between different
Article
Several groups have provided evidence that positron emission tomography (PET) and single-photon emission computed tomography (SPECT) neuroreceptor imaging techniques might be applied to measure acute fluctuations in dopamine (DA) synaptic concentration in the living human brain. Competition between DA and radioligands for binding to D2 receptor is the principle underlying this approach. This new application of neuroreceptor imaging provides a dynamic measurement of neurotransmission that is likely to be informative to our understanding of neuropsychiatric conditions. This article reviews and discusses the body of data supporting the feasibility and potential of this imaging paradigm. Endogenous competition studies performed in rodents, nonhuman primates, and humans are first summarized. After this overview, the validity of the model underlying the interpretation of these imaging data is critically assessed. The current reference model is defined as the occupancy model, since changes in radiotracer binding potential (BP) are assumed to be directly caused by changes in occupancy of D2 receptors by DA. Experimental data supporting this model are presented. The evidence that manipulation of DA synaptic levels induces change in the BP of several D2 radiotracers (catecholamines and benzamides) is unequivocal. The fact that these changes in BP are mediated by changes in DA synaptic concentration is well documented. The relationship between the magnitude of BP changes measured with PET or SPECT and the magnitude of changes in DA concentration measured by microdialysis supports the use of these noninvasive techniques to measure changes in neurotransmission. On the other hand, several observations remain unexplained. First, the amphetamine-induced changes in the BP of D2 receptor antagonists [123I]IBZM and [11C]raclopride last longer than amphetamine-induced changes in DA extracellular concentration. Second, nonbenzamide D2 receptor antagonists, such as spiperone and pimozide, are not affected by changes in DA release, or are affected in a direction opposite to that predicted by the occupancy model. Similar observations are reported with D1 radiotracers. These results suggest that the changes in BP following changes in DA concentration might not be fully accounted by a simple occupancy model. Specifically, the data are reviewed supporting that agonist-mediated receptor internalization might play an important role in characterizing receptor-ligand interactions. Finally, it is proposed that a better understanding of the mechanism underlying the effects observed with benzamides is essential to develop this imaging technique to other receptor systems.
Article
Compartment models are the basis for most physiologically based quantification of nuclear medicine data. Although some software packages are available for this purpose, many are expensive, run on relatively few types of computers or are of limited capability, and cannot be extended because of the unavailability of source code. Consequently, institutions with modeling expertise often develop software for themselves, which has the disadvantages of lack of standardization and possible replication of effort. Therefore, general-purpose compartment-modeling software distributed with source code would be a welcome resource for the nuclear medicine community. We formulated a mathematic framework within which compartment models containing unimolecular and bimolecular (receptor saturation) kinetics can be described. We implemented this framework within MATLAB and call the resultant software COMKAT (Compartment Model Kinetic Analysis Tool). COMKAT simplifies the process of defining and solving standard blood flow, 18F-FDG, and receptor models as well as models of a user's own design. In particular, COMKAT automatically defines and implements state, analytic sensitivity, and Jacobian equations. Given these, COMKAT can perform simulations in which model outputs are solved for specified parameter values, thereby allowing the user to predict how sensitive data are to these parameters. In addition, COMKAT can be used to estimate values for the parameters by fitting model output to experimental data. COMKAT is equipped with command-line and graphic user interfaces from which the user can access these features. Examples of these applications are presented along with validation and performance summaries. COMKAT is a useful software tool and is available without cost to researchers, at www.nuclear.uhrad.com/comkat.
Article
We present a technique for automatically assigning a neuroanatomical label to each voxel in an MRI volume based on probabilistic information automatically estimated from a manually labeled training set. In contrast to existing segmentation procedures that only label a small number of tissue classes, the current method assigns one of 37 labels to each voxel, including left and right caudate, putamen, pallidum, thalamus, lateral ventricles, hippocampus, and amygdala. The classification technique employs a registration procedure that is robust to anatomical variability, including the ventricular enlargement typically associated with neurological diseases and aging. The technique is shown to be comparable in accuracy to manual labeling, and of sufficient sensitivity to robustly detect changes in the volume of noncortical structures that presage the onset of probable Alzheimer's disease.
Article
Parental caregiving includes a set of highly conserved behaviors and mental states that may reflect both an individual's genetic endowment and the early experience of being cared for as a child. This review first examines the mental and behavioral elements of early parental caregiving in humans. Second, we consider what is known about the neurobiological substrates of maternal behaviors in mammalian species including some limited human data. Third, we briefly review the evidence that specific genes encode proteins that are crucial for the development of the neural substrates that underlie specific features of maternal behavior. Fourth, we review the emerging literature on the "programming" role of the intrauterine environment and postnatal caregiving environment in shaping subsequent maternal behavior. We conclude that there are critical developmental windows during which the genetically determined microcircuitry of key limbic-hypothalamic-midbrain structures are susceptible to early environmental influences and that these influences powerfully shape an individual's responsivity to psychosocial stressors and their resiliency or vulnerability to various forms of human psychopathology later in life.
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.
Conference Paper
A new algorithm for variance reduction on random coincidences (VRR) has been validated for the HRRT. VRR is crucial to achieve quantitation for low statistics dynamic studies reconstructed with iterative methods based on ordinary Poisson model. On HRRT, VRR cannot be performed in projection space since individual LOR's are mixed after histogramming in parallel projection space using nearest neighbor approximation and axial compression. The proposed algorithm uses the classical random rate equation on the 4.5 109LOR's. However, crystal singles are registered at block level and have lower deadtime than coincidences. Variations in layer identification with countrate were reported biasing random estimation from block singles. Our method overcomes these problems by estimating the singles per crystal from delayed coincidences. A singles map is created histogramming every delayed event into 2 singles. Each element represents the number of coincidences between that crystal and the ones in the 5 opposite coincident heads. The algorithm finds iteratively the crystal singles rates compatible with the delayed coincidence events. The method has been validated on decaying phantoms. We compared estimated and measured block singles to identify deadtime difference between singles and coincidences
Article
Reports on a new numerical implementation of the single-scatter simulation scatter correction algorithm for 3D PET. Its primary advantage over tile original implementation is that it is a much faster calculation, currently requiring less than 30 sec execution time per bed position for an adult thorax, thus making clinical whole-body scatter correction more practical. The new code runs on a single processor workstation CPU instead of a vector processor array, making it highly portable. It is modular and independent of any particular reconstruction code. The computed scatter contribution is now intrinsically scaled relative to the emission image and no longer requires normalization to the scatter tails in the sinogram when all activity is contained within the field of view, making it more robust against noise. The new algorithm has been verified against the original code on both phantom and human thorax studies. Initial results indicate that scatter correction may be accurately performed following, instead of prior to, either 3D reprojection or Fourier rebinning. Some evidence is presented that the single-scatter operator, when applied to an uncorrected emission image provides reasonable compensation for multiple scatter
Functional anatomy of the hypothalamus and pituitary. Endotext
  • Rm Lechan
  • R Toni
  • Lj De Groot
Lechan RM, Toni R (2013) Functional anatomy of the hypothalamus and pituitary. Endotext, eds De Groot LJ, et al. (MDText.com, Inc., South Dartmouth, MA).
Reference Module in Neuroscience and Biobehavioral Psychology: Parental Behavior
  • M Numan
Numan M (2017) Reference Module in Neuroscience and Biobehavioral Psychology: Parental Behavior (Elsevier, Amsterdam).
Substituted benzamides as ligands for visualization of dopamine receptor binding in the human brain by positron emission tomography
  • L Farde
Farde L, et al. (1985) Substituted benzamides as ligands for visualization of dopamine receptor binding in the human brain by positron emission tomography. Proc Natl Acad Sci USA 82(11):3863–3867.
Social effects of oxytocin in humans: Context and person matter
  • J A Bartz
  • Zaki
  • Bolger
  • Ochsner
  • Bartz JA
Bartz JA, Zaki J, Bolger N, Ochsner KN (2011) Social effects of oxytocin in humans: Context and person matter. Trends Cogn Sci 15(7):301–309.
Functional anatomy of the hypothalamus and pituitary
  • R M Lechan
  • R Toni
Functional anatomy of the hypothalamus and pituitary. Endotext
  • Rm Lechan
  • Toni
  • Lechan RM