Child brain exhibits a multi-rhythmic response to attachment cues

Sensitive infant care tunes a frontotemporal interbrain network in adolescence

Caregiving plays a critical role in children's cognitive, emotional, and psychological well-being. In the current longitudinal study, we investigated the enduring effects of early maternal behavior on processes of interbrain synchrony in adolescence. Mother-infant naturalistic interactions were filmed when infants were 3-4 months old and interactions were coded for maternal sensitivity and intrusiveness with the Coding Interactive Behavior Manual. In early adolescence (Mean = 12.30, SD = 1.25), mother-adolescent interbrain synchrony was measured using hyperscanning EEG during a naturalistic interaction of positive valence. Guided by previous hyperscanning studies, we focused on interbrain connections within the right frontotemporal interbrain network. Results indicate that maternal sensitivity in early infancy was longitudinally associated with neural synchrony in the right interbrain frontotemporal network. Post-hoc comparisons highlighted enhancement of mother-adolescent frontal-frontal connectivity, a connection that has been implicated in parent-child social communication. In contrast, maternal intrusiveness in infancy was linked with attenuation of interbrain synchrony in the right interbrain frontotemporal network. Sensitivity and intrusiveness are key maternal social orientations that have shown to be individually stable in the mother-child relationship from infancy to adulthood and foreshadow children's positive and negative social-emotional outcomes, respectively. Our findings are the first to demonstrate that these two maternal orientations play a role in enhancing or attenuating the child's interbrain frontotemporal network, which sustains social communication and affiliation. Results suggest that the reported long-term impact of maternal sensitivity and intrusiveness may relate, in part, to its effects on tuning the child's brain to sociality.

Generation WhatsApp: inter-brain synchrony during face-to-face and texting communication

Texting has become one of the most prevalent ways to interact socially, particularly among youth; however, the effects of text messaging on social brain functioning are unknown. Guided by the biobehavioral synchrony frame, this pre-registered study utilized hyperscanning EEG to evaluate interbrain synchrony during face-to-face versus texting interactions. Participants included 65 mother-adolescent dyads observed during face-to-face conversation compared to texting from different rooms. Results indicate that both face-to-face and texting communication elicit significant neural synchrony compared to surrogate data, demonstrating for the first time brain-to-brain synchrony during texting. Direct comparison between the two interactions highlighted 8 fronto-temporal interbrain links that were significantly stronger in the face-to-face interaction compared to texting. Our findings suggest that partners co-create a fronto-temporal network of inter-brain connections during live social exchanges. The degree of improvement in the partners' right-frontal-right-frontal connectivity from texting to the live social interaction correlated with greater behavioral synchrony, suggesting that this well-researched neural connection may be specific to face-to-face communication. Our findings suggest that while technology-based communication allows humans to synchronize from afar, face-to-face interactions remain the superior mode of communication for interpersonal connection. We conclude by discussing the potential benefits and drawbacks of the pervasive use of texting, particularly among youth.

Attachment Reminders Trigger Widespread Synchrony across Multiple Brains

Infant stimuli elicit widespread neural and behavioral response in human adults, and such massive allocation of resources attests to the evolutionary significance of the primary attachment. Here, we examined whether attachment reminders also trigger cross-brain concordance and generate greater neural uniformity, as indicated by intersubject correlation. Human mothers were imaged twice in oxytocin/placebo administration design, and stimuli included four ecological videos of a standard unfamiliar mother and infant: two infant/mother alone (Alone) and two mother-infant dyadic contexts (Social). Theory-driven analysis measured cross-brain synchrony in preregistered nodes of the parental caregiving network (PCN), which integrates subcortical structures underpinning mammalian mothering with cortical areas implicated in simulation, mentalization, and emotion regulation, and data-driven analysis assessed brain-wide concordance using whole-brain parcellation. Results demonstrated widespread cross-brain synchrony in both the PCN and across the neuroaxis, from primary sensory/somatosensory areas, through insular-cingulate regions, to temporal and prefrontal cortices. The Social context yielded significantly more cross-brain concordance, with PCNs striatum, parahippocampal gyrus, superior temporal sulcus, ACC, and PFC displaying cross-brain synchrony only to mother-infant social cues. Moment-by-moment fluctuations in mother-infant social synchrony, ranging from episodes of low synchrony to tightly coordinated positive bouts, were tracked online by cross-brain concordance in the preregistered ACC. Findings indicate that social attachment stimuli, representing evolutionary-salient universal cues that require no verbal narrative, trigger substantial interbrain concordance and suggest that the mother-infant bond, an icon standing at the heart of human civilization, may function to glue brains into a unified experience and bind humans into social groups.SIGNIFICANCE STATEMENT Infant stimuli elicit widespread neural response in human adults, attesting to their evolutionary significance, but do they also trigger cross-brain concordance and induce neural uniformity among perceivers? We measured cross-brain synchrony to ecological mother-infant videos. We used theory-driven analysis, measuring cross-brain concordance in the parenting network, and data-driven analysis, assessing brain-wide concordance using whole-brain parcellation. Attachment cues triggered widespread cross-brain concordance in both the parenting network and across the neuroaxis. Moment-by-moment fluctuations in behavioral synchrony were tracked online by cross-brain variability in ACC. Attachment reminders bind humans' brains into a unitary experience and stimuli characterized by social synchrony enhance neural similarity among participants, describing one mechanism by which attachment bonds provide the neural template for the consolidation of social groups.

Developmental Cascades Link Maternal-Newborn Skin-to-Skin Contact with Young Adults' Psychological Symptoms, Oxytocin, and Immunity; Charting Mechanisms of Developmental Continuity from Birth to Adulthood

Premature birth disrupts the continuity of maternal-newborn bodily contact, which underpins the development of physiological and behavioral support systems. Utilizing a unique cohort of mother-preterm dyads who received skin-to-skin contact (Kangaroo Care, KC) versus controls, and following them to adulthood, we examined how a touch-based neonatal intervention impacts three adult outcomes; anxiety/depressive symptoms, oxytocin, and secretory immunoglobulin A (s-IgA), a biomarker of the immune system. Consistent with dynamic systems' theory, we found that links from KC to adult outcomes were indirect, mediated by its effects on maternal mood, child attention and executive functions, and mother-child synchrony across development. These improvements shaped adult outcomes via three mechanisms; (a) "sensitive periods", where the infancy improvement directly links with an outcome, for instance, infant attention linked with higher oxytocin and lower s-IgA; (b) "step-by-step continuity", where the infancy improvement triggers iterative changes across development, gradually shaping an outcome; for instance, mother-infant synchrony was stable across development and predicted lower anxiety/depressive symptoms; and (c) "inclusive mutual-influences", describing cross-time associations between maternal, child, and dyadic factors; for instance, from maternal mood to child executive functions and back. Findings highlight the long-term impact of a birth intervention across development and provide valuable insights on the mechanisms of "developmental continuity", among the key topics in developmental research.

Mother-Infant Brain-to-Brain Synchrony Patterns Reflect Caregiving Profiles

Biobehavioral synchrony, the coordination of physiological and behavioral signals between mother and infant during social contact, tunes the child's brain to the social world. Probing this mechanism from a two-brain perspective, we examine the associations between patterns of mother-infant inter-brain synchrony and the two well-studied maternal behavioral orientations-sensitivity and intrusiveness-which have repeatedly been shown to predict positive and negative socio-emotional outcomes, respectively. Using dual-electroencephalogram (EEG) recordings, we measure inter-brain connectivity between 60 mothers and their 5- to 12-month-old infants during face-to-face interaction. Thirty inter-brain connections show significantly higher correlations during the real mother-infant face-to-face interaction compared to surrogate data. Brain-behavior correlations indicate that higher maternal sensitivity linked with greater mother-infant neural synchrony, whereas higher maternal intrusiveness is associated with lower inter-brain coordination. Post hoc analysis reveals that the mother-right-frontal-infant-left-temporal connection is particularly sensitive to the mother's sensitive style, while the mother-left-frontal-infant-right-temporal connection indexes the intrusive style. Our results support the perspective that inter-brain synchrony is a mechanism by which mature brains externally regulate immature brains to social living and suggest that one pathway by which sensitivity and intrusiveness exert their long-term effect may relate to the provision of coordinated inputs to the social brain during its sensitive period of maturation.

Technologically-assisted communication attenuates inter-brain synchrony

The transition to technologically-assisted communication has permeated all facets of human social life; yet, its impact on the social brain is still unknown and the effects may be particularly intense during periods of developmental transitions. Applying a two-brain perspective, the current preregistered study utilized hyperscanning EEG to measure brain-to-brain synchrony in 62 mother-child pairs at the transition to adolescence (child age; M = 12.26, range 10-14) during live face-to-face interaction versus technologically-assisted remote communication. The live interaction elicited 9 significant cross-brain links between densely inter-connected frontal and temporal areas in the beta range [14-30 Hz]. Mother's right frontal region connected with the child's right and left frontal, temporal, and central regions, suggesting its regulatory role in organizing the two-brain dynamics. In contrast, the remote interaction elicited only 1 significant cross-brain-cross-hemisphere link, attenuating the robust right-to-right-brain connectivity during live social moments that communicates socio-affective signals. Furthermore, while the level of social behavior was comparable between the two interactions, brain-behavior associations emerged only during the live exchange. Mother-child right temporal-temporal synchrony linked with moments of shared gaze and the degree of child engagement and empathic behavior correlated with right frontal-frontal synchrony. Our findings indicate that human co-presence is underpinned by specific neurobiological processes that should be studied in depth. Much further research is needed to tease apart whether the "Zoom fatigue" experienced during technological communication may stem, in part, from overload on more limited inter-brain connections and to address the potential cost of social technology for brain maturation, particularly among youth.

Rodent models of early adversity: Impacts on developing social behavior circuitry and clinical implications

Flexible and context-appropriate social functioning is key for survival across species. This flexibility also renders social behavior highly plastic, particularly during early development when attachment to caregiver can provide a template for future social processing. As a result, early caregiving adversity can have unique and lasting impacts on social behavior and even confer vulnerability to psychiatric disorders. However, the neural circuit mechanisms translating experience to outcome remain poorly understood. Here, we consider social behavior scaffolding through the lens of reward and threat processing. We begin by surveying several complementary rodent models of early adversity, which together have highlighted impacts on neural circuits processing social cues. We next explore these circuits underlying perturbed social functioning with focus on dopamine (DA) and its role in regions implicated in social and threat processing such as the prefrontal cortex (PFC), basolateral amygdala (BLA) and the lateral habenula (LHb). Finally, we turn to human populations once more to examine how altered DA signaling and LHb dysfunction may play a role in social anhedonia, a common feature in diagnoses such as schizophrenia and major depressive disorder (MDD). We argue that this translational focus is critical for identifying specific features of adversity that confer heightened vulnerability for clinical outcomes involving social cue processing.

Investigating default mode network connectivity disruption in children of mothers with depression

BACKGROUND

Exposure to maternal major depressive disorder (MDD) bears long-term negative consequences for children's well-being; to date, no research has examined how exposure at different stages of development differentially affects brain functioning.

AIMS

Utilising a unique cohort followed from birth to preadolescence, we examined the effects of early versus later maternal MDD on default mode network (DMN) connectivity.

METHOD

Maternal depression was assessed at birth and ages 6 months, 9 months, 6 years and 10 years, to form three groups: children of mothers with consistent depression from birth to 6 years of age, which resolved by 10 years of age; children of mothers without depression; and children of mothers who were diagnosed with MDD in late childhood. In preadolescence, we used magnetoencephalography and focused on theta rhythms, which characterise the developing brain.

RESULTS

Maternal MDD was associated with disrupted DMN connectivity in an exposure-specific manner. Early maternal MDD decreased child connectivity, presenting a profile typical of early trauma or chronic adversity. In contrast, later maternal MDD was linked with tighter connectivity, a pattern characteristic of adult depression. Aberrant DMN connectivity was predicted by intrusive mothering in infancy and lower mother-child reciprocity and child empathy in late childhood, highlighting the role of deficient caregiving and compromised socio-emotional competencies in DMN dysfunction.

CONCLUSIONS

The findings pinpoint the distinct effects of early versus later maternal MDD on the DMN, a core network sustaining self-related processes. Results emphasise that research on the influence of early adversity on the developing brain should consider the developmental stage in which the adversity occured.

Neural Representation of the Parent-Child Attachment from Infancy to Adulthood

Attachment theory is built on the assumption of consistency; the mother–infant bond is thought to underpin the life-long representations individuals construct of attachment relationships. Still, consistency in the individual’s neural response to attachment-related stimuli representing his or her entire relational history has not been investigated. Mothers and children were followed across two decades and videotaped in infancy (3–6 months), childhood (9–12 years) and young adulthood (18–24 years). In adulthood, participants underwent functional magnetic resonance imaging while exposed to videos of own mother–child interactions (Self) vs unfamiliar interactions (Other). Self-stimuli elicited greater activations across preregistered nodes of the human attachment network, including thalamus-to-brainstem, amygdala, hippocampus, anterior cingulate cortex (ACC), insula and temporal cortex. Critically, self-stimuli were age-invariant in most regions of interest despite large variability in social behavior, and Bayesian analysis showed strong evidence for lack of age-related differences. Psycho–physiological interaction analysis indicated that self-stimuli elicited tighter connectivity between ACC and anterior insula, consolidating an interface associating information from exteroceptive and interceptive sources to sustain attachment representations. Child social engagement behavior was individually stable from infancy to adulthood and linked with greater ACC and insula response to self-stimuli. Findings demonstrate overlap in circuits sustaining parental and child attachment and accord with perspectives on the continuity of attachment across human development.

Effects of familiarity on child brain networks when listening to a storybook reading: A magneto-encephalographic study

Parent-child book reading is important for fostering the development of various lifelong cognitive and social abilities in young children. Despite numerous reports describing the effects of familiarity on shared reading for children, the exact neural basis of the functional network architecture remains unclear. We conducted Magnet-Encephalographic (MEG) experiments using graph theory to elucidate the role of familiarity in shared reading in a child's brain network and to measure the connectivity dynamics of a child while Listening to Storybook Reading (LSBR), which represents the daily activity of shared book reading between the child and caregiver. The LSBR task was performed with normally developing preschool- and school-age children (N = 15) under two conditions: reading by their own mother (familiar condition) vs. an experimenter (unfamiliar condition). We used the phase lag index (PLI), which captures synchronization of MEG signals, to estimate functional connectivity. For the whole brain network topology, an undirected weighted graph was produced using 68 brain regions as nodes and interregional PLI values as edges for five frequency bands. Behavioral data (i.e., the degree of attention and facial expressions) were evaluated from video images of the child's face during the two conditions. Our results showed enhanced widespread functional connectivity in the alpha band during the mother condition. In the mother condition, the whole brain network in the alpha band exhibited topographically high local segregation with high global integration, indicating an increased small-world property. Results of the behavioral analysis revealed that children were more attentive and showed more positive facial expressions in the mother condition than in the experimenter condition. Behavioral data were significantly correlated with graph metrics in the mother condition but not in the experimenter condition. In this study, we identified the neural correlates of a familiarity effect in children's brain connectivity dynamics during LSBR. Furthermore, these familiarity-related brain dynamics were closely linked to the child's behavior. Graph theory applied to MEG data may provide useful insight into the familiarity-related child brain response in a naturalistic setting and its relevance to child attitudes.

The Embodied-Enactive-Interactive Brain: Bridging Neuroscience and Creative Arts Therapies

The recognition and incorporation of evidence-based neuroscientific concepts into creative arts therapeutic knowledge and practice seem valuable and advantageous for the purpose of integration and professional development. Moreover, exhilarating insights from the field of neuroscience coincide with the nature, conceptualization, goals, and methods of Creative Arts Therapies (CATs), enabling comprehensive understandings of the clinical landscape, from a translational perspective. This paper contextualizes and discusses dynamic brain functions that have been suggested to lie at the heart of intra- and inter-personal processes. Touching upon fundamental aspects of the self and self-other interaction, the state-of-the-art neuroscientific-informed views will shed light on mechanisms of the embodied, predictive and relational brain. The conceptual analysis introduces and interweaves the following contemporary perspectives of brain function: firstly, the grounding of mental activity in the lived, bodily experience will be delineated; secondly, the enactive account of internal models, or generative predictive representations, shaped by experience, will be defined and extensively deliberated; and thirdly, the interpersonal simulation and synchronization mechanisms that support empathy and mentalization will be thoroughly considered. Throughout the paper, the cross-talks between the brain and the body, within the brain through functionally connected neural networks and in the context of agent-environment dynamics, will be addressed. These communicative patterns will be elaborated on to unfold psychophysiological linkage, as well as psychopathological shifts, concluding with the neuroplastic change associated with the formulation of CATs. The manuscript suggests an integrative view of the brain-body-mind in contexts relevant to the therapeutic potential of the expressive creative arts and the main avenues by which neuroscience may ground, enlighten and enrich the clinical psychotherapeutic practice.

Towards understanding neurocognitive mechanisms of parenting: Maternal behaviors and structural brain network organization in late childhood

A substantial body of knowledge suggests that exposure to adverse family environments - including violence and neglect - influences many aspects of brain development. Relatively less attention has been directed toward the influence of "normative" differences in parenting behaviors. Given the rapid brain reorganization during late childhood, parenting behaviors are particularly likely to impact the structure of the brain during this time. This study investigated associations between maternal parenting behaviors and the organization of structural brain networks in late childhood, as measured by structural covariance. One hundred and forty-five typically developing 8-year-olds and their mothers completed questionnaire measures and two observed interaction tasks; magnetic resonance imaging (MRI) scans were obtained from the children. Measures of maternal negative, positive, and communicative behavior were derived from the interaction tasks. Structural covariance networks based on partial correlations between cortical thickness estimates were constructed and estimates of modularity were obtained using graph theoretical analysis. High levels of negative maternal behavior were associated with low modularity. Minimal support was found for an association between positive maternal behaviors and modularity and between maternal communicative behaviors and modularity. Our findings suggest that variation in negative maternal behavior is associated with the structural organization of brain networks in children.

Synchronous caregiving from birth to adulthood tunes humans' social brain

A birth-to-adulthood study tested the effects of maternal–newborn contact and synchronous caregiving on the social processing brain in human adults. For two decades, we followed preterm and full-term neonates, who received or lacked initial maternal bodily contact, repeatedly observing mother–child social synchrony. We measured the brain basis of affect-specific empathy in young adulthood to pinpoint regions sensitive to others’ distinct emotions. Maternal–newborn contact enhanced social synchrony across development, which, in turn, predicted amygdalar and insular sensitivity to emotion-specific empathy. Findings demonstrate the long-term effects of maternal caregiving in humans, similar to their role in other mammals, particularly in tuning core regions implicated in salience detection, simulation, and interoception that sustain empathy and human attachment.

Mammalian young are born with immature brain and rely on the mother’s body and caregiving behavior for maturation of neurobiological systems that sustain adult sociality. While research in animal models indicated the long-term effects of maternal contact and caregiving on the adult brain, little is known about the effects of maternal–newborn contact and parenting behavior on social brain functioning in human adults. We followed human neonates, including premature infants who initially lacked or received maternal–newborn skin-to-skin contact and full-term controls, from birth to adulthood, repeatedly observing mother–child social synchrony at key developmental nodes. We tested the brain basis of affect-specific empathy in young adulthood and utilized multivariate techniques to distinguish brain regions sensitive to others’ distinct emotions from those globally activated by the empathy task. The amygdala, insula, temporal pole (TP), and ventromedial prefrontal cortex (VMPFC) showed high sensitivity to others’ distinct emotions. Provision of maternal–newborn contact enhanced social synchrony across development from infancy and up until adulthood. The experience of synchrony, in turn, predicted the brain’s sensitivity to emotion-specific empathy in the amygdala and insula, core structures of the social brain. Social synchrony linked with greater empathic understanding in adolescence, which was longitudinally associated with higher neural sensitivity to emotion-specific empathy in TP and VMPFC. Findings demonstrate the centrality of synchronous caregiving, by which infants practice the detection and sharing of others’ affective states, for tuning the human social brain, particularly in regions implicated in salience detection, interoception, and mentalization that underpin affect sharing and human attachment.

The integration of social and neural synchrony: a case for ecologically valid research using MEG neuroimaging

The recent decade has seen a shift from artificial and environmentally deprived experiments in neuroscience to real-life studies on multiple brains in interaction, coordination and synchrony. In these new interpersonal synchrony experiments, there has been a growing trend to employ naturalistic social interactions to evaluate mechanisms underlying synchronous neuronal communication. Here, we emphasize the importance of integrating the assessment of neural synchrony with measurement of nonverbal behavioral synchrony as expressed in various social contexts: relaxed social interactions, planning a joint pleasurable activity, conflict discussion, invocation of trauma, or support giving and assess the integration of neural and behavioral synchrony across developmental stages and psychopathological conditions. We also showcase the advantages of magnetoencephalography neuroimaging as a promising tool for studying interactive neural synchrony and consider the challenge of ecological validity at the expense of experimental rigor. We review recent evidence of rhythmic information flow between brains in interaction and conclude with addressing state-of-the-art developments that may contribute to advance research on brain-to-brain coordination to the next level.

Interactional synchrony: signals, mechanisms and benefits

Many group-living animals, humans included, occasionally synchronize their behavior with that of conspecifics. Social psychology and neuroscience have attempted to explain this phenomenon. Here we sought to integrate results around three themes: the stimuli, the mechanisms and the benefits of interactional synchrony. As regards stimuli, we asked what characteristics, apart from temporal regularity, prompt synchronization and found that stimulus modality and complexity are important. The high temporal resolution of the auditory system and the relevance of socio-emotional information endow auditory, multimodal, emotional and somewhat variable and adaptive sequences with particular synchronizing power. Looking at the mechanisms revealed that traditional perspectives emphasizing beat-based representations of others' signals conflict with more recent work investigating the perception of temporal regularity. Timing processes supported by striato-cortical loops represent any kind of repetitive interval sequence fairly automatically. Additionally, socio-emotional processes supported by posterior superior temporal cortex help endow such sequences with value motivating the extent of synchronizing. Synchronizing benefits arise from an increased predictability of incoming signals and include many positive outcomes ranging from basic information processing at the individual level to the bonding of dyads and larger groups.

Social Behavior as a Transdiagnostic Marker of Resilience

The recent shift from psychopathology to resilience and from diagnosis to functioning requires the construction of transdiagnostic markers of adaptation. This review describes a model of resilience that is based on the neurobiology of affiliation and the initial condition of mammals that mature in the context of the mother's body and social behavior. The model proposes three tenets of resilience-plasticity, sociality, and meaning-and argues that coordinated social behavior stands at the core sustaining resilience. Two lines in the maturation of coordinated social behavior are charted, across animal evolution and throughout human development, culminating in the mature human reciprocity of empathy, mutuality, and perspective-taking. Cumulative evidence across ages and clinical conditions and based on our behavioral coding system demonstrates that social reciprocity, defined by plasticity at the individual, dyadic, and group levels, denotes resilience, whereas the two poles of disengagement/avoidance and intrusion/rigidity characterize specific psychopathologies, each with a distinct behavioral signature. Attention to developmentally sensitive markers and to the dimension of meaning in human sociality may open new, behavior-based pathways to resilience.

Defining Immediate Effects of Sensitive Periods on Infant Neurobehavioral Function

During a sensitive period associated with attachment, the infant brain has unique circuitry that enables the specialized adaptive behaviors required for survival in infancy. This infant brain is not an immature version of the adult brain. Within the attachment relationship, the infant remains close (proximity seeking) to the caregiver for nurturing and survival needs, but the caregiver also provides the immature infant with the physiological regulation interaction needed before self-regulation matures. Here we provide examples from the human and animal literature that illustrate some of these regulatory functions during sensitive periods, recent advances demonstrating the supporting transient neural mechanisms, and how these systems go awry in the absence of species-expected caregiving.

Human attachments shape interbrain synchrony toward efficient performance of social goals

The human brain has undergone massive expansion across primate evolution through life amidst multi-layered social attachments; within families, among friends, and between clan members and this enabled humans to coordinate their brains with those of others toward the execution of complex social goals.  We examined how human attachments facilitate efficient, resource-sensitive performance of social goals by balancing neural and behavioral synchrony. Using hyperscanning EEG, we collected neural data from male-female pairs in three groups (N=158, 79 pairs); long-term couples, best friends, and unfamiliar group members, during two ecologically-valid naturalistic tasks; motor coordination and empathy giving.  Across groups and tasks, neural synchrony was supported by behavior coordination and orchestrated multiple neural rhythms.  In the goal-directed motor task, interbrain synchrony implicated beta and gamma rhythms localized to sensorimotor areas. Couples showed the highest neural synchrony combined with greatest behavioral synchrony and such brain-behavior linkage resulted in speedy performance, conserving energy in the long run.  The socially-oriented empathy task triggered neural synchrony in widely-distributed sensorimotor and bilateral temporal regions, integrated alpha, beta, and gamma rhythms, and implicated brain-behavior complementarity; couples displayed the highest behavioral synchrony combined with lowest neural synchrony toward greatest felt support while strangers exhibited the opposite pattern.  Findings suggest that human attachments provide a familiar backdrop of temporal regularities, required for the brain's allostatic function, and interbrain and behavioral synchrony are sculpted by familiarity and closeness toward resource-sensitive performance of survival-related social goals, toiled by two.

Early Parenting Intervention Effects on Brain Responses to Maternal Cues Among High-Risk Children

OBJECTIVE

Early adversity is correlated with increased risk for negative outcomes, including psychopathology and atypical neurodevelopment. The authors aimed to test the causal impact of an early parenting intervention (Attachment and Biobehavioral Catch-Up; ABC) on children's neural processing of parent cues and on psychosocial functioning in a longitudinal randomized clinical trial.

METHODS

Participants (N=68, mean age, 10.0 years [SD=0.8 years]) were 46 high-risk children whose parents were randomly assigned to receive either the ABC intervention (N=22) or a control intervention (N=24) while the children were infants, in addition to a comparison sample of low-risk children (N=22). During functional MRI scanning, children viewed pictures of their own mothers and of a stranger.

RESULTS

Children in the ABC condition showed greater maternal cue-related activation than children in the control condition in clusters of brain regions, including the precuneus, the cingulate gyrus, and the hippocampus, regions commonly associated with social cognition. Additionally, greater activity in these regions was associated with fewer total behavior problems. There was an indirect effect of early intervention on middle childhood psychosocial functioning mediated through increased activity in brain regions in response to maternal cues.

CONCLUSIONS

These results suggest that early parenting intervention (in this case the ABC intervention) can enhance brain regions supporting children's social cognitive development. In addition, the findings highlight these brain effects as a possible neural pathway through which ABC may prevent future behavior problems among high-risk children, yielding psychosocial benefits that endure through at least middle childhood without the need to intervene with the child directly.

The Temporal and Spatial Dynamics of Cortical Emotion Processing in Different Brain Frequencies as Assessed Using the Cluster-Based Permutation Test: An MEG Study

The processing of emotions in the human brain is an extremely complex process that extends across a large number of brain areas and various temporal processing steps. In the case of magnetoencephalography (MEG) data, various frequency bands also contribute differently. Therefore, in most studies, the analysis of emotional processing has to be limited to specific sub-aspects. Here, we demonstrated that these problems can be overcome by using a nonparametric statistical test called the cluster-based permutation test (CBPT). To the best of our knowledge, our study is the first to apply the CBPT to MEG data of brain responses to emotional stimuli. For this purpose, different emotionally impacting (pleasant and unpleasant) and neutral pictures were presented to 17 healthy subjects. The CBPT was applied to the power spectra of five brain frequencies, comparing responses to emotional versus neutral stimuli over entire MEG channels and time intervals within 1500 ms post-stimulus. Our results showed significant clusters in different frequency bands, and agreed well with many previous emotion studies. However, the use of the CBPT allowed us to easily include large numbers of MEG channels, wide frequency, and long time-ranges in one study, which is a more reliable alternative to other studies that consider only specific sub-aspects.

What is resilience: an affiliative neuroscience approach

Resilience - a key topic in clinical science and practice - still lacks a clear conceptualization that integrates its evolutionary and human-specific features, refrains from exclusive focus on fear physiology, incorporates a developmental approach, and, most importantly, is not based on the negation (i.e., absence of symptoms following trauma). Building on the initial condition of mammals, whose brain matures in the context of the mother's body and caregiving behavior, we argue that systems and processes that participate in tuning the brain to the social ecology and adapting to its hardships mark the construct of resilience. These include the oxytocin system, the affiliative brain, and biobehavioral synchrony, all characterized by great flexibility across phylogenesis and ontogenesis. Three core features of resilience are outlined: plasticity, sociality and meaning. Mechanisms of sociality by which coordinated action supports diversity, endurance and adaptation are described across animal evolution. Humans' biobehavioral synchrony matures from maternal attuned behavior in the postpartum to adult-adult relationships of empathy, perspective-taking and intimacy, and extends from the mother-child relationship to other affiliative bonds throughout life, charting a fundamental trajectory in the development of resilience. Findings from three high-risk cohorts, each tapping a distinct disruption to maternal-infant bonding (prematurity, maternal depression, and early life stress/trauma), and followed from birth to adolescence/young adulthood, demonstrate how components of the neurobiology of affiliation confer resilience and uniquely shape the social brain.

Adverse caregiving in infancy blunts neural processing of the mother

The roots of psychopathology frequently take shape during infancy in the context of parent-infant interactions and adversity. Yet, neurobiological mechanisms linking these processes during infancy remain elusive. Here, using responses to attachment figures among infants who experienced adversity as a benchmark, we assessed rat pup cortical local field potentials (LFPs) and behaviors exposed to adversity in response to maternal rough and nurturing handling by examining its impact on pup separation-reunion with the mother. We show that during adversity, pup cortical LFP dynamic range decreased during nurturing maternal behaviors, but was minimally impacted by rough handling. During reunion, adversity-experiencing pups showed aberrant interactions with mother and blunted cortical LFP. Blocking pup stress hormone during either adversity or reunion restored typical behavior, LFP power, and cross-frequency coupling. This translational approach suggests adversity-rearing produces a stress-induced aberrant neurobehavioral processing of the mother, which can be used as an early biomarker of later-life pathology.

Chronic trauma impairs the neural basis of empathy in mothers: Relations to parenting and children's empathic abilities

Early life stress carries long-term negative consequences for children's well-being and maturation of the social brain. Here, we utilize a unique cohort to test its effects on mothers' social brain, targeting mothers' neural empathic response in relation to caregiving and child empathic abilities. Mother-child dyads living in a zone of repeated war-related trauma were followed from early childhood and mother-child behavioral synchrony was repeatedly observed. At pre-adolescence(11-13 years) children's empathic abilities were assessed and mothers(N = 88, N = 44 war-exposed) underwent magnetoencephalography(MEG) while exposed to vicarious pain. All mothers showed alpha suppression in sensorimotor regions, indicating automatic response to others' pain. However, trauma-exposed mothers did not exhibit gamma oscillations in viceromotor cortex, a neural marker of mature empathy which utilizes interoceptive mechanisms for higher-order understanding and does not emerge before adulthood. Mother-child synchrony across the first decade predicted mothers' viceromotor gamma, and both synchrony and maternal viceromotor gamma mediated the relations between war-exposure and child empathic abilities, possibly charting a cross-generational pathway from mothers' mature neural empathy to children's empathic capacities. Our findings are first to probe the maternal social brain in adolescence in relation to parenting and underscore the need for targeted interventions to mothers raising children in contexts of chronic stress.

Exposure to early and persistent maternal depression impairs the neural basis of attachment in preadolescence

Maternal depression increases child vulnerability to psychopathology, loneliness, and social maladjustment; yet, its long-term effects on the social brain are unknown. In this prospective longitudinal study we examined the impact of early and persistent maternal depression on the neural basis of attachment in preadolescence. A community cohort was followed in two groups; children exposed to maternal depression from birth to 6 years and healthy controls. At 9 months and 6 years, mother-child interactions were coded for maternal sensitivity and affect synchrony and salivary oxytocin levels were assessed at 6 years. At preadolescence (11-13 years), children underwent magnetoencephalography (MEG) while exposed to own versus unfamiliar mother-child interaction. Own interaction elicited greater response in beta- and gamma-band oscillations across a wide cluster in temporal and insular cortices, including the Superior Temporal Sulcus, Superior Temporal Gyrus, Inferior Temporal Gyrus, and insula. Beta activations were predicted by maternal sensitivity across early childhood and gamma by affect synchrony. Oxytocin was related to beta response to social cues. Maternal depression impacted child's brain response in two ways. First, maternal depression significantly increased the prevalence of child affective disorder and such children showed no neural differentiation between attachment and non-attachment stimuli. Second, maternal depression decreased maternal sensitivity, affect synchrony, and child oxytocin across early childhood and these were longitudinally associated with aberrant neural response to attachment-specific and social-general cues in preadolescence. Our findings are the first to describe mechanisms by which maternal depression impairs the neural basis of attachment at the transition to adolescence and advocate the need for relationship-focused early interventions.

Darwin's Other Dilemmas and the Theoretical Roots of Emotional Connection

Modern scientific theories of emotional behavior, almost without exception, trace their origin to Charles Darwin, and his publications On the Origin of Species (1859) and The Expression of the Emotions in Man and Animals (1872). The most famous dilemma Darwin acknowledged as a challenge to his theory of evolution through natural selection was the incomplete Sub-Cambrian fossil record. However, Darwin struggled with two other rarely referenced theoretical and scientific dilemmas that confounded his theories about emotional behavior. These included (1) the origin of social instincts (e.g., altruism, empathy, reciprocity and cooperation) and the reasons for their conservation in evolution and (2) the peripheral control of heart rate vis-à-vis emotional behavior outside of consciousness. Darwin acknowledged that social instincts are critical to the survival of some species, but had difficulty aligning them with his theory of natural selection in humans. Darwin eventually proposed that heart rate and emotions are controlled via one's intellect and cortical mechanisms, and that instinctive behavior is genetically programmed and inherited. Despite ongoing efforts, these two theoretical dilemmas are debated to this day. Simple testable hypotheses have yet to emerge for the biological mechanisms underlying instinctive behavior or the way heart rate is controlled in infants. In this paper, we review attempts to resolve these issues over the past 160 years. We posit that research and theories that supported Darwin's individualistic brain-centric and genetic model have become an "orthodox" Western view of emotional behavior, one that produced the prevailing behavioral construct of attachment as developed by John Bowlby. We trace research and theories that challenged this orthodoxy at various times, and show how these challenges were repeatedly overlooked, rejected, or misinterpreted. We review two new testable theories, emotional connection theory and calming cycle theory, which we argue resolve the two dilemmas We show emerging scientific evidence from physiology and a wide variety of other fields, as well from clinical trials among prematurely born infants, that supports the two theories. Clinical implications of the new theories and possible new ways to assess risk and intervene in emotional, behavioral and developmental disorders are discussed.

The Neural Basis of Empathy and Empathic Behavior in the Context of Chronic Trauma

Background: Accumulating evidence in social neuroscience suggests that mature human empathy relies on the integration of two types of processes: a lower-order process mainly tapping into automatic and sensory mechanisms and a higher-order process involving affect and cognition and modulated by top-down control. Studies have also indicated that neural measures of empathy often correlate with behavioral measures of empathy. Yet, little is known on the effects of chronic trauma on the neural and behavioral indices of empathy and the associations among them. Methods: Mothers exposed to chronic war-related trauma and nonexposed controls (N = 88, N = 41 war-exposed) underwent magnetoencephalography (MEG) while watching stimuli depicting vicarious emotional distress. Maternal empathic behavior was assessed during mother-child interaction involving a joint task. Results: Empathy-evoking vignettes elicited response in alpha rhythms in a network involving both sensorimotor and viceromotor (anterior insula) regions, suggesting integration of the sensory and affective components of empathy. Whereas exposure to chronic stress did not affect the level of neural activations in this network, it reduced maternal empathic behavior. Furthermore, trauma exposure impaired the coherence of brain and behavior; only among controls, but not among trauma-exposed mothers, the neural basis of empathy was predicted by maternal empathic behavior. Conclusions: Chronic stress takes a toll on the mother's empathic ability and indirectly impacts the neural basis of empathy by disrupting the coherence of brain and behavior.