HIV status affects PTSD symptom severity, psychophysiology, and heart rate variability in women with low but not high exposure to childhood maltreatment.

Objective: People living with HIV (PLWH) experience high rates of childhood trauma exposure, which is a significant risk factor for the development of posttraumatic stress disorder (PTSD). Because Black Americans living in urban environments are exposed to high levels of trauma, suffer from chronic PTSD, and are at increased risk for HIV infection, it is important to understand how HIV status interacts with childhood maltreatment to influence PTSD symptom severity and underlying psychophysiology. Methods: The current cross-sectional study assessed whether HIV status interacts with childhood maltreatment to influence PTSD symptom severity and heart rate variability during a dark-enhanced startle (DES) task in 88 Black women with (n=30) and without HIV (n=58). Results: HIV was associated with greater PTSD symptom severity only in women with low levels of childhood maltreatment (p=.024). Startle potentiation during DES was highest in women living without HIV and with high childhood maltreatment (p=.018). In women who had experienced low levels of childhood maltreatment, respiratory sinus arrhythmia (RSA) was lower during the dark phase of DES in women living without HIV than women living with HIV (WLWH), (p=.046). RSA during the light phase of DES was lower in WLWH than in women living without HIV (p=.042). Conclusion: In the current sample of Black women, HIV status was associated with PTSD symptom severity in a manner dependent on level of childhood maltreatment, suggesting that HIV status may be an important factor to consider for behavioral and pharmacological treatment strategies for PTSD. Additionally, HIV status is associated with lower percent potentiation to darkness and lower RSA during the light phase of DES, suggesting physiological mechanisms by which HIV may contribute to PTSD symptoms in individuals exposed to low levels of childhood maltreatment.

Self- and co-regulation of physiological activity during mother-daughter interactions: The role of adolescent non-suicidal self-injury.

BACKGROUND: Non-suicidal self-injury (NSSI) is a significant public health concern that is thought to increase risk for future self-injurious behaviors, including suicide attempts. Notably, NSSI is especially prevalent among adolescents, which underscores a critical need to identify modifiable risk factors that could be targeted to reduce future risk. The current study examined self- and co-regulation of physiological responses during mother-daughter interactions in adolescent girls with and without a history of NSSI. METHODS: Participants were 60 girls aged 13-17 with (n = 27) and without (n = 33) a history of NSSI and their mothers. Adolescents and their mothers completed positive and negative interaction tasks during which physiological reactivity was assessed via respiratory sinus arrhythmia (RSA). RESULTS: Using Actor-Partner Interdependence Modeling (APIM), we found that adolescents with an NSSI history demonstrated a higher RSA setpoint than adolescents without this history during the negative, but not positive, interaction task. In addition, there were differences in co-regulation during the negatively valenced interaction, such that mothers of daughters with NSSI were more reactive to fluctuations in their daughters' RSA than mothers of daughters without an NSSI history. CONCLUSIONS: These findings highlight intra- and interpersonal aspects of physiological dysregulation associated with NSSI that could provide promising targets of intervention to reduce future risk in adolescent girls.

The interactive roles of narrative processing and emotion negativity/lability in relation to autonomic coordination.

Emotion regulation (ER) is a multifaceted construct, involving behavioral, cognitive, and physiological processes. Although autonomic coordination is theorized to play a crucial role in adaptive functioning, few studies have examined how different individual and contextual factors together may contribute to such coordination. This study examined the joint influences of narrative processing and emotional negativity/lability (N/L) traits on the coordination of the sympathetic and parasympathetic nervous systems in a sample of 112 children, ages 8-12 years (Mage = 10.15 years, SD = 1.33). Children completed a stress-induction task followed by an interview about the task. Children's trait-level N/L was assessed via parent-report on the Emotion Regulation Checklist. Narrative processing was assessed and coded based on children's narrative accounts of the event (i.e., causal coherence, overall emotional tone). Indexes of sympathetic (skin conductance response, SCR) and parasympathetic (respiratory sinus arrhythmia, RSA) functioning were derived from physiological data obtained during the interview. Results revealed that children's trait-level N/L and narrative processing of the stressful event interacted to predict the RSA-SCR correlation. Specifically, children who were high on either N/L or narrative causal coherence, but not both, demonstrated significant RSA-SCR correlation. Similarly, children with high N/L and negative-to-neutral narratives, as well as those with low N/L and neutral-to-positive narratives, exhibited significant RSA-SCR correlation. This work provides empirical evidence that narrative processing and trait N/L, together with RSA-SCR correlation, work in tandem to regulate emotional arousal.

Respiratory sinus arrhythmia (RSA) dynamics matter for children's emotion regulation: RSA inertia and instability within a stress task.

The present study employed two key dynamic indicators (i.e., inertia and instability) to the psychophysiological research of child emotion regulation (ER) and examined whether respiratory sinus arrhythmia (RSA) dynamics were associated with child ER during a stress task. Eighty-nine Chinese school-age children (Mage = 8.77 years, SD = 1.80 years; 46.1% girls) and their primary caregivers participated in the study. After controlling for RSA static reactivity, multiple regression analyses indicated that lower RSA inertia was related to fewer in-task negative emotions rated by children and their caregivers, and higher RSA instability was associated with better child trait ER. This study introduces physiological indicators of the dynamic aspects of parasympathetic activity to the study of child ER.

Age-dependent associations between RSA reactivity, affective and cognitive regulation, and psychopathology risk in young children exposed to varying levels of socioeconomic disadvantage.

This study examined autonomic nervous system activity (respiratory sinus arrhythmia [RSA]) as a biomarker of psychopathology in an ethnically and socioeconomically diverse sample (N = 57) of young children ages 4-7 years. RSA was measured at baseline and across four standardized tasks designed to assess self-regulation in both affective (i.e., "hot") and cognitive (i.e., "cool") contexts during early childhood. Our findings reveal that age moderated RSA activity, such that reduced RSA suppression was associated with a heightened risk of externalizing problems among older children during "cool" and "hot" contexts; for younger children, only RSA suppression during "hot" contexts predicted externalizing risk. The influence of socioeconomic disadvantage did not moderate the relationship between RSA and the risk of psychopathology, and there were minimal associations between RSA suppression and internalizing symptoms at this age range. These results suggest that autonomic variability may be a more effective predictor of psychopathology risk in older children, perhaps as they transition into formal schooling and face increasingly complex cognitive and social demands. Findings have implications for the identification of psychopathology in early developmental periods when regulation over emotions becomes essential for academic and social success.

Grandmother-grandchild physiological synchrony in Chinese three-generation families: Links with child emotion regulation.

The current study examined the characteristics of physiological synchrony between grandmothers and grandchildren in Chinese three-generation families, and the associations between physiological synchrony and child emotion regulation. The participants included 92 children (age 8-10-year old) and their grandmothers. Respiratory sinus arrhythmia (RSA) was collected from both grandmothers and their grandchildren throughout a collaborative drawing task and a conflict discussion task. Child emotion regulation was measured using the Children's Emotional Management Scale. We found no evidence for an overall pattern of concordant or discordant synchrony within dyads. Instead, there was great variability in patterns of synchrony across dyads. During the collaborative drawing task, concordance in grandmother's RSA and grandchildren's subsequent RSA was linked with better emotion regulation. During the conflict discussion, concordance in grandmother's RSA and grandchildren's simultaneous RSA was linked with poorer emotion regulation. These results suggest that grandmother-grandchild synchrony in different directions, time lags, and contexts has different influences on children's emotion regulation. The findings of this study highlight the importance of contextual physiological co-regulation between Chinese children and their grandmothers for children's social-emotional development.

RSA instability in mothers of preschoolers and adolescents is related to observations of supportive parenting behaviors.

Respiratory sinus arrhythmia (RSA; a measure of respiratory modulation of vagal control of heart rate) is a dynamic process. For mothers, RSA functioning has been associated with depressive symptoms and coincides with supportive parenting. However, research has largely focused on RSA suppression (i.e., difference score from rest to stress task). The present study examined depressive symptoms and supportive parenting with RSA instability-a dynamic measure of the magnitude of RSA change across a task. In two samples of mothers (N = 210), one with preschoolers (Study 1: n = 108, Mage = 30.68 years, SD = 6.06, 47.0% Black, 43.0% White) and one with adolescents (Study 2: n = 102, Mage = 35.51, SD = 6.51, 75.2% Black), RSA instability was calculated during an interaction task. In both studies, instrumental supportive parenting behaviors were negatively related to RSA instability. Findings provide preliminary support for RSA instability as an indicator of physiological dysregulation for mothers.

Assessing Children's Autonomic Nervous System Activity During Structured Tasks: A Feasibility and Reliability Study in Ghana.

The significance of physiological regulation in relation to behavioral and emotional regulation is well documented, but primarily in economically advantaged contexts. Few studies have been conducted in low- and middle-income countries. We investigated the feasibility and reliability of measuring autonomic nervous system (ANS) activity and behavior during challenge tasks in 30 children aged 8-10 years in Ghana during two visits, 1 week apart. Completeness of ANS data ranged from 80% to 100% across all tasks. There was low-to-moderate test-retest reliability of video mood induction (VMI) emotion ratings and balloon analog risk task (BART) pumps (r = 0.34-0.52). VMI elicited higher targeted emotion ratings in Visit 2 than Visit 1. Respiratory sinus arrhythmia (RSA) was higher, and pre-ejection period (PEP) was longer at Visit 2 than Visit 1 for baseline and both tasks. RSA was higher at baseline than during the VMI anger scene at Visit 1, whereas PEP was shorter at baseline than during all VMI emotion scenes at Visit 2. RSA was higher at baseline than during BART at both visits. In conclusion, ANS data collection within evocative and arousing challenge tasks was feasible in Ghana, and the tasks were generally reliable and effective in eliciting target emotions and risk-taking behavior in this sample.

Emotion dysregulation and reward responsiveness as predictors of autonomic reactivity to an infant cry task among substance-using pregnant and postpartum women.

Maternal substance use may interfere with optimal parenting, lowering maternal responsiveness during interactions with their children. Previous work has identified maternal autonomic nervous system (ANS) reactivity to parenting-relevant stressors as a promising indicator of real-world parenting behaviors. However, less is known about the extent to which individual differences in emotion dysregulation and reward processing, two mechanisms of substance use, relate to maternal ANS reactivity in substance-using populations. The current study examined associations among emotion dysregulation, reward responsiveness, and ANS reactivity to an infant cry task among 77 low-income and substance-using women who were either pregnant (n = 63) or postpartum (n = 14). Two indicators of ANS functioning were collected during a 9 min computerized infant cry task (Crybaby task): respiratory sinus arrhythmia (RSA) and pre-ejection period. Mothers also completed self-reported measures of emotion dysregulation and reward responsiveness. Analyses revealed that trait emotion regulation was associated with RSA reactivity to the Crybaby task, such that greater emotion dysregulation was associated with greater RSA reduction during the infant cry task than lower emotion dysregulation. Reward responsiveness was not significantly associated with either indicator of ANS reactivity to the task. Findings revealed distinct patterns of associations linking emotion dysregulation with ANS reactivity during a parenting-related computerized task, suggesting that emotion regulation may be a key intervention target for substance-using mothers.

Resting respiratory sinus arrhythmia moderates the within-person relations of parental emotional expressivity and children's prosocial behaviors.

Parental supportive emotional expressivity could contribute to children's prosocial behaviors, and such an effect may differ for children with different levels of resting respiratory sinus arrhythmia (RSA). This study disentangled the stable differences across dyads (i.e., between-person effects) from the dynamic associations between parental expressivity and children's prosocial behaviors within dyads (i.e., within-person effects) and determined how resting RSA functioned as a susceptibility factor in such effects. The longitudinal design consisted of three measurements with a 1-year interval performed among 208 school-aged children (48.6% girls; Han nationality) and their parents (153 mothers and 55 fathers). The initial measurement was conducted when the children were 7 years old (Mage  = 7.13, SDage  = .33). Resting RSA was calculated at the first measurement; parents reported children's prosocial behaviors and parental expressivity at each of the three measurements. The results demonstrated significant between- and within-person effects of parental expressivity on children's prosocial behaviors and found a moderating role of children's resting RSA in the within-person effects. These findings suggest that children displayed more prosocial behaviors when parents showed more supportive expressivity both across and within dyads, and higher resting RSA operated as a differential susceptibility factor in the intraindividual fluctuations in parental expressivity.

Weakened sympathetic response and lower parasympathetic activity in intimate partner violence perpetrators when empathizing: Influence of autonomous activation in affective approach and prosocial behavior.

The autonomic nervous system (ANS) functioning has been proposed as a relevant method to characterize the therapeutic needs of intimate partner violence (IPV) perpetrators. Nevertheless, research has neglected the influence of the ANS on socio-affective functions in this population. The aim of the present study was to analyze the psychophysiological activity of IPV perpetrators (n = 52) compared to controls (n = 46) following an empathic induction task, performed through negative emotion-eliciting videos. We employed two general ANS markers (heart rate [HR] and respiratory rate [RR]), two sympathetic-related indexes (pre-ejection period [PEP] and skin conductance level [SCL]) and a parasympathetic biomarker (respiratory sinus arrhythmia [RSA]). Additionally, we explored the impact of psychophysiological activity on prosocial behavior using Hare's donation procedure. Compared to controls, IPV perpetrators reported lower HR and SCL following the task, as well as longer PEP, suggesting an attenuated sympathetic response to others' distress. No differences in the RSA response pattern were found, however, IPV perpetrators displayed lower overall RSA levels throughout the protocol, indicative of reduced parasympathetic activity. Besides, while no differences in prosocial performance were observed, greater sympathetic responses and overall parasympathetic activity predicted increased donations across the sample. Thus, a high sympathetic and parasympathetic activity might influence the occurrence of prosocial behavior. The present study provides further evidence supporting that IPV perpetrators cope differently with others' negative emotions. In line with this biopsychosocial perspective, insights are gained on the emotional processing of IPV perpetrators which, in turn, could contribute to improve IPV psychotherapeutic programs.

Deactivation, hyperactivation, and anomalous content in the attachment script assessment: stability over time and significance for parenting behavior and physiology.

This study examined the stability of Attachment Script Assessment (ASA) deactivation, hyperactivation, and anomalous content and their significance for parenting outcomes in mothers (Mage = 31 years; 78% White/European American) and 6-month-old infants. Comparable to ASA secure base script knowledge (SBSK), mothers' ASA deactivation, hyperactivation, and anomalous content were significantly, moderately stable over two years (r's = .40 - .43). Mothers' ASA hyperactivation and anomalous content were associated with greater maternal intrusiveness, whereas ASA deactivation was associated with greater detachment and less intrusiveness. Only ASA anomalous content was associated with lower maternal sensitivity. Mothers' ASA deactivation was associated with less dynamic change in respiratory sinus arrhythmia during the Still-Face Procedure-reflective of limited mobilization of physiological resources to support responding to infants. Findings support the validity of ASA deactivation, hyperactivation, and anomalous content scripts, and demonstrate their utility in examining adult attachment stability and predictive significance for parent-child outcomes.

Nonlinear Moderation Effect of Vagal Regulation on the Link between Childhood Trauma and Adolescent Internalizing and Externalizing Symptoms.

Childhood trauma is a leading early adverse environment that increases psychopathological symptoms. Respiratory sinus arrhythmia (RSA) suppression to challenges as a marker of self-regulation is found to linearly moderate the link between early adverse experiences and psychopathological symptoms, but yielding mixed findings. The present study examined the relationships between childhood trauma and internalizing and externalizing symptoms via a 1.5-year longitudinal design and the quadratic moderation effect of RSA suppression on these relationships among adolescents. In November 2021 (T1), the final sample of 275 Chinese adolescents (Mage = 12.94, SDage = 0.79; 49.82% females) completed the short form of Childhood Trauma Questionnaire and the Achenbach Youth Self-Report-2001 and underwent a speech task during which their baseline RSA and stress exposure RSA were obtained. In June 2023 (T2), 251 adolescents completed the Achenbach Youth Self-Report-2001. Results showed that childhood trauma at T1 was positively correlated with internalizing and externalizing symptoms at T1 and T2. RSA suppression to stress quadratically moderated these associations, such that adolescents with moderate rather than higher or lower RSA suppression had the least internalizing and externalizing symptoms at T1 and T2 when exposed to childhood trauma. The findings suggest that moderate RSA suppression to stress as a marker of optimal vagal regulation buffers the risk of developmental psychopathology from early adverse experiences.

Root mean square of successive differences is not a valid measure of parasympathetic reactivity during slow deep breathing.

Deep breathing exercises are the second most used complementary health approach in the United States. Two heart rate variability (HRV) parameters, the root mean square of successive differences (RMSSD) and the respiratory sinus arrhythmia (RSA), are used to assess parasympathetic reactivity to deep breathing, but they are often not in agreement. Our purpose was to determine the cause of the disagreement. We investigated HRV parameters in 38 subjects during baseline, deep breathing, and recovery. Here we show that RMSSD as a measure of parasympathetic reactivity is unreliable; it does not reflect the increase in HRV during deep breathing as determined by RSA. We observed a decrease in RMSSD values despite a marked increase in HRV as determined by RSA and the standard deviation of normal heartbeat interval (SDNN) in healthy subjects and patients with functional bowel disorders. We show that RSA captures all aspects of HRV, whereas successive differences in heart rate intervals are only a small part of HRV, with decreasing variability during deep breathing in most subjects. We present a new measure of calculating RSA during deep breathing that may become an essential tool for researchers and clinicians. We also provide a unique visualization of the increased heart rate variability during deep breathing. Hence, RMSSD cannot be used to assess parasympathetic reactivity during deep breathing; using RSA is recommended. The use of RMSSD in previous influential studies may have led to erroneous conclusions about parasympathetic reactivity during deep breathing. Its continued use may undervalue the effects of the autonomic nervous system in slow deep breathing.

Awe Sparks Prosociality in Children.

Rooted in the novel and the mysterious, awe is a common experience in childhood, but research is almost silent with respect to the import of this emotion for children. Awe makes individuals feel small, thereby shifting their attention to the social world. Here, we studied the effects of art-elicited awe on children's prosocial behavior toward an out-group and its unique physiological correlates. In two preregistered studies (Study 1: N = 159, Study 2: N = 353), children between 8 and 13 years old viewed movie clips that elicited awe, joy, or a neutral (control) response. Children who watched the awe-eliciting clip were more likely to spend their time on an effortful task (Study 1) and to donate their experimental earnings (Studies 1 and 2), all toward benefiting refugees. They also exhibited increased respiratory sinus arrhythmia, an index of parasympathetic nervous system activation associated with social engagement. We discuss implications for fostering prosociality by reimagining children's environments to inspire awe at a critical age.

Maternal invalidation and child RSA reactivity to frustration interact to predict teacher-reported aggression among at-risk preschoolers.

BACKGROUND: Aggression is a transdiagnostic indicator of risk and represents one of the most common reasons children are referred for mental health treatment. Theory and research highlight the impact of maternal invalidation on child aggression and suggest that its influence may vary based on differences in child physiological reactivity. Moreover, the interaction between these risk factors may be particularly pronounced among children of mothers with emotion regulation (ER) difficulties. The current study examined the independent and interactive effects of maternal invalidation and child physiological reactivity to frustration on teacher-reported aggression in an at-risk sample of preschool children. METHOD: Participants included 77 mothers (Mage = 33.17 years, s.d. = 4.83; 35% racial/ethnic minority) and their children (Mage = 42.48 months; s.d. = 3.78; 56% female; 47% racial/ethnic minority). Groups of mothers with and without clinician-rated ER difficulties reported on maternal invalidation, and child respiratory sinus arrhythmia (RSA) was assessed continuously during a frustration task as an indicator of physiological reactivity. Teachers or daycare providers reported on child aggression. RESULTS: Results demonstrated positive associations between maternal ER difficulties and both maternal invalidation and child RSA reactivity to frustration. As expected, the interaction between maternal invalidation and child RSA reactivity was significant, such that higher maternal invalidation and greater child RSA reactivity to frustration predicted more aggression in a daycare or preschool setting. Importantly, this effect was demonstrated while controlling for demographic covariates and baseline RSA. CONCLUSIONS: Findings are in line with diathesis-stress and biosocial models of risk and point to multiple targets for prevention and early intervention.

Risk for internalizing symptom development in young children: Roles of child parasympathetic reactivity and maternal depression and anxiety exposure in early life.

Intergenerational transmission of internalizing disorders (anxiety and depression) is well documented, but the responsible pathways are underspecified. One possible mechanism is via programming of the child's parasympathetic nervous system (PNS). For example, maternal depression and anxiety, via multiple pathways, may heighten child PNS reactivity, which has been linked to increased risk for internalizing disorders. Heightened PNS reactivity also may sensitize a child to their environment, increasing the vulnerability to developing psychopathology when exposed to stressors, such as maternal psychopathology. In a prospective longitudinal study of mother-child dyads (N = 446), we examined relations among maternal depression and anxiety symptoms when children were infants and aged 3 and 5 years, child respiratory sinus arrythmia (RSA) reactivity (measure of PNS reactivity) at 3 years, and child internalizing symptoms at age 5 years. Consistent with an adaptive calibration perspective, analyses tested the roles of child RSA reactivity as both a mediator and a moderator of associations between maternal and child symptoms. Greater child RSA reactivity in response to a fearful video predicted higher internalizing symptoms among children exposed to higher levels of maternal depression or anxiety symptoms at age 5 years (moderation effects). Child RSA reactivity did not mediate relations between maternal depression or anxiety symptoms in infancy and child internalizing symptoms at age 5 years. The results suggest that heightened PNS reactivity may represent a biological vulnerability to stressful environments early in life: When coupled with maternal depression or anxiety exposure, child PNS reactivity may promote the development of internalizing psychopathology in early childhood.

Associations between physical activity and autonomic function during deep breathing test: the Swedish CArdioPulmonary bioImage Study (SCAPIS).

PURPOSE: The deep breathing test (DBT) is a sensitive test of cardiovagal function. The aim of this study was to explore associations between physical activity and sedentary time, measured by accelerometer, and autonomic function, using DBT. METHODS: In the Swedish Cardio-Pulmonary bioImage Study, men and women aged 50-64 were randomly invited from the general population. A total of 4325 subjects who underwent DBT and assessment of physical activity and sedentary time by accelerometery were included. ECG files from 1-min DBT were used to calculate measures of respiratory sinus arrhythmia [RSA; expiration-inspiration (E-I) difference and E/I ratio], heart rate variability [HRV; root mean square of successive differences (RMSSD), standard deviation of heart rates and mean circular resultant]. Low RSA and HRV was defined as the lowest 10% in the population. RESULTS: For accelerometer-assessed physical activity, there were significant associations between high percentage of sedentary time and low E/I (p < 0.01), and low RMSSD (p < 0.01) in an age- and sex-adjusted model, and between percentage of sedentary time and low RMSSD (p = 0.04) in a risk factor-adjusted model. Low RMSSD was less common in those with a high percentage of moderate to vigorous physical activity (p = 0.04, after risk-factor adjustment). These associations became non-significant when further adjusting for heart rate. CONCLUSION: We report associations between degree of physical activity and indices of autonomic dysfunction in a large population. The relationships were no longer significant after adjustments for heart rate, indicating that the relationship between physical activity and cardiovagal function partly is accounted for by reduced heart rate.

The development of forms and functions of aggression during early childhood: A temperament-based approach.

This study used a short-term longitudinal design with theoretically derived preregistered hypotheses and analyses to examine the role of temperament in the development of forms (i.e., physical and relational) and functions (i.e., proactive and reactive) of aggressive behavior in early childhood (N = 300, M age = 44.70 months, SD = 4.38, 44% girls). Temperament was measured via behavioral reports of emotional dysregulation, fearlessness/daring, and rule internalization/empathy and, in a subsample that completed a physiological assessment, via skin conductance and respiratory sinus arrhythmia. Emotion dysregulation generally served as a risk factor for all subtypes of aggression, with evidence of stronger associations with reactive as compared to proactive functions of relational aggression for girls. Daring predicted increases in physical aggression, especially among boys, and rule internalization predicted decreases in relational aggression, especially among girls. Rule internalization mediated longitudinal associations between daring and proactive relational aggression for girls. Some evidence also emerged supporting associations between adaptive functioning (i.e., high empathy, high respiratory sinus arrhythmia) and proactive functions of aggression. Findings highlight distinct temperamental risk factors for physical versus relational aggression and provide partial support for gender-linked theories of the development of aggression.

Biological sensitivity to context as a dyadic construct: An investigation of child-parent RSA synchrony among low-SES youth.

Parenting behaviors are significantly linked to youths' behavioral adjustment, an association that is moderated by youths' and parents' self-regulation. The biological sensitivity to context theory suggests that respiratory sinus arrhythmia (RSA) indexes youths' varying susceptibility to rearing contexts. However, self-regulation in the family context is increasingly viewed as a process of "coregulation" that is biologically embedded and involves dynamic Parent×Child interactions. No research thus far has examined physiological synchrony as a dyadic biological context that may moderate associations between parenting behaviors and preadolescent adjustment. Using a two-wave sample of 101 low-socioeconomic status (SES) families (children and caretakers; mean age 10.28 years), we employed multilevel modeling to examine dyadic coregulation during a conflict task, indicated by RSA synchrony, as a moderator of the linkages between observed parenting behaviors and preadolescents' internalizing and externalizing problems. Results showed that high dyadic RSA synchrony resulted in a multiplicative association between parenting and youth adjustment. High dyadic synchrony intensified the relations between parenting behaviors and youth behavior problems, such that in the context of high dyadic synchrony, positive and negative parenting behaviors were associated with decreased and increased behavioral problems, respectively. Parent-child dyadic RSA synchrony is discussed as a potential biomarker of biological sensitivity in youth.