Physiological linkage to an interaction partner is negatively associated with stability in sympathetic nervous system responding

How and Why People Synchronize: An Integrated Perspective

Academic AbstractInterpersonal synchrony, the alignment of behavior and/or physiology during interactions, is a pervasive phenomenon observed in diverse social contexts. Here we synthesize across contexts and behaviors to classify the different forms and functions of synchrony. We provide a concise framework for classifying the manifold forms of synchrony along six dimensions: periodicity, discreteness, spatial similarity, directionality, leader-follower dynamics, and observability. We also distill the various proposed functions of interpersonal synchrony into four interconnected functions: reducing complexity and improving understanding, accomplishing joint tasks, strengthening social connection, and influencing partners' behavior. These functions derive from first principles, emerge from each other, and are accomplished by some forms of synchrony more than others. Effective synchrony flexibly adapts to social goals and more synchrony is not always better. Our synthesis offers a shared framework and language for the field, allowing for better cross-context and cross-behavior comparisons, generating new hypotheses, and highlighting future research directions.

Neurophysiological markers of asymmetric emotional contagion: implications for organizational contexts

Emotions play a vital role within organizations, impacting various crucial aspects of work such as job satisfaction, performance, and employee well-being. Understanding how emotional states spread in organizational settings is therefore essential. Recent studies have highlighted that a leader's emotional state can influence their followers, with significant consequences on job performance. Leaders thus possess the ability to influence their employees' psychological state and, consequently, their well-being. However, the biological underpinnings of emotional contagion from leaders to followers remain unexplored. The field of interpersonal (neuro)physiology, which involves recording brain and peripheral activity of multiple individuals during interactions, holds great potential for investigating this phenomenon. Analyzing the time-lagged synchronization of neurophysiological activity during interactions may serve as a measure of the leader's influence on their followers in organizational contexts. In this "mini review," we examine empirical studies that have employed interpersonal (neuro)physiology to quantify the asymmetrical contagion of emotions in different contexts. Asymmetrical contagion was operationalized as the unidirectional influence exerted by one individual (i.e., the "sender") to another one (i.e., the "receiver"), whereby the receiver's state can be predicted by the sender's one. The reviewed literature reveals that delayed synchronization of physiological states is a widespread phenomenon that may underpin the transmission of emotions. These findings have significant implications for various aspects of organizational life, including leader-to-employee communication, and could drive the development of effective leadership training programs. We propose that Organizational Neuroscience may benefit from including interpersonal neurophysiology in its methodological toolkit for laboratory and field studies of leader-follower dynamics.

Dataset of parent-child hyperscanning functional near-infrared spectroscopy recordings

The term “hyperscanning” refers to the simultaneous recording of multiple individuals’ brain activity. As a methodology, hyperscanning allows the investigation of brain-to-brain synchrony. Despite being a promising technique, there is a limited number of publicly available functional Near-infrared Spectroscopy (fNIRS) hyperscanning recordings. In this paper, we report a dataset of fNIRS recordings from the prefrontal cortical (PFC) activity of 33 mother-child dyads and 29 father-child dyads. Data was recorded while the parent-child dyads participated in an experiment with two sessions: a passive video attention task and a free play session. Dyadic metadata, parental psychological traits, behavioural annotations of the play sessions and information about the video stimuli complementing the dataset of fNIRS signals are described. The dataset presented here can be used to design, implement, and test novel fNIRS analysis techniques, new hyperscanning analysis tools, as well as investigate the PFC activity in participants of different ages when they engage in passive viewing tasks and active interactive tasks.

Measurement(s)	Blood Oxygen Level-Dependent Response
Technology Type(s)	Functional Near-Infrared Spectroscopy
Factor Type(s)	Parenting Stress • Parental Bonding • Attachment Style
Sample Characteristic - Organism	Homo sapiens
Sample Characteristic - Location	Singapore

Emotional Linkage as a Moderator of Emotional Reactivity Effect on Partners' Depressive Symptoms

Introduction: Romantic partners’ emotions show a degree of interdependence, a process that is often described as emotional linkage. The current study sought to test the effects of emotional linkage in emotionally reactive individuals (i.e., those who easily become emotionally aroused and find it hard to regulate their emotions) and their partners. Specifically, we examined the interplay between emotional linkage and reactivity in predicting partners’ depressive symptoms over time. Method: To assess emotional linkage and reactivity, we collected daily diary data from two samples of cohabiting couples (Ncouples=76 and 84 in samples 1 and 2, respectively). Partners’ depressive symptoms were assessed before and after the diary. Results: In dyads with low emotional linkage men's emotional reactivity predicted their greater depressive symptoms in Sample 1, and women's greater depressive symptoms in Sample 2. Discussion: The study's results suggest that dyads’ emotional linkage can moderate the negative effects of men's emotional reactivity on their and their partners’ psychological distress.

Self-disclosure is associated with adrenocortical attunement between new acquaintances

Adrenocortical attunement-similarity in hypothalamic-pituitary-adrenal (HPA) axis activity-has been well-documented in close relationships (e.g., between romantic partners, parents and children, and close friends). However, little is known about adrenocortical attunement during early relationship formation. In the current study, we examine dyadic adrenocortical attunement during a guided conversation in which two new acquaintances (N = 140 people, 70 dyads), who were university students or adults in the community, answered questions about themselves. Dyads were randomly assigned to answer questions designed to elicit dyad members to reveal a high or low amount of personal information (i.e., to self-disclose at high or low levels). We collected saliva samples (assayed for cortisol) before and after the conversation, and we coded behavioral self-disclosure-the extent to which people revealed their thoughts, feelings, and facts about themselves-during the conversation. As expected, dyads who were assigned to ask and answer high self-disclosure questions disclosed more than those assigned to ask and answer low self-disclosure questions. In addition, greater self-disclosure during the conversation was associated with greater similarity in cortisol change-that is, dyad members who revealed more about themselves experienced more similar cortisol changes in response to their conversation. This work reveals one social process through which adrenocortical attunement occurs during early relationship formation, and, in doing so, describes how our physiological functioning is linked to those around us-even people we have just met.

Influence of stress on physiological synchrony in a stressful versus non-stressful group setting

Physiological synchrony (PS) is defined as the co-occurrence and interdependence of physiological activity between interaction partners. Previous research has uncovered numerous influences on the extent of PS, such as relationship type or individual characteristics. Here, we investigate the influence of acute stress on PS. We do so in a setting in which PS was not promoted, but contact between group members was explicitly minimized. We reanalyzed cortisol, alpha-amylase, and subjective stress data from 138 participants (mean age = \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$23.48 \pm 3.99$$\end{document}23.48±3.99, 47.1% female) who previously underwent the Trier Social Stress Test for groups (TSST-G) or a non-stressful control task together, collected as part of a larger project by Popovic et al. (Sci Rep 10: 7845, 2020). Using a stability and influence model, an established method to test for synchrony, we tested whether individuals’ cortisol and alpha-amylase concentrations could be predicted by group members’ levels. We found cortisol PS in participants who were in the same group, the extent of which was stronger in the non-stressful control condition. For alpha-amylase, participants were synchronized as well; furthermore, there was an interaction between previous stress levels and PS. This suggests that while synchrony of both stress markers can occur in group settings even with spurious interaction, stressor exposure might attenuate its extent. We argue that if PS occurs in a sample where interaction was minimal, the phenomenon might be more widespread than previously thought. Furthermore, stressor exposure might influence whether a situation allows for PS. We conclude that PS should be investigated within group settings with various degrees of social interaction to further expose mechanisms of and influence on PS.

Physiological linkage during interactions between doctors and cancer patients

INTRODUCTION

Doctors and patients influence each other when interacting and, as a result, can become similar to each other in affect and behavior. In the current work, we examine whether they also become similar to each other on a moment-to-moment basis in their physiological responses. Specifically, we examine physiological linkage-how much a doctor's (or patient's) physiological response predicts a patient's (or doctor's) response at a subsequent time interval-and whether this changes over the course of doctor-patient relationships (measured as the number of consultations held for each unique doctor-patient dyad).

METHODS

We collected interbeat interval responses (IBI) continuously during consultations between oncologists and patients undergoing cancer treatment (N = 102 unique doctor-patient interactions) at a hospital in Austria.

RESULTS

Physiological linkage varied by an interaction between role (doctor vs. patient) and relationship length (in a non-linear, quadratic pattern). Patients showed significant positive linkage to their doctors (i.e., doctors' physiological responses positively, significantly predicted patients' responses) in relationships that spanned three to eight consultations together. Patients were not linked to their doctors in shorter or longer relationships. Doctors were never significantly linked to their patients, meaning that patients' physiological responses never predicted doctors' responses.

CONCLUSION

These results reveal that, by influencing patients' physiological responses on a moment-to-moment basis, doctors may have even more influence over patients' physiology than previously known.

Being 'in sync'-is interactional synchrony the key to understanding the social brain?

The past couple of decades produced a surge of interest in interaction synchrony. Moving from the study of behavioral coordination to investigating the coordination of psychophysiological and brain activity, relevant research has tackled a broad range of interactional settings with a multitude of measurement and analysis tools. This method diversity produced a host of interesting results converging on the fact that individuals engaged in social exchange tend to temporally align external as well as internal processes. Moreover, there appears to be a reciprocal relationship between the individuals' affective bond and the extent of synchronization, which together benefit interaction outcomes. Notably, however, the current breadth of study approaches creates challenges for the field, including how to compare findings and how to develop a theoretical framework that unites and directs ongoing research efforts. More concerted efforts are called for to achieve the conceptual and methodological clarity needed to answer core questions and enabling a balanced pursuit of both synchronous and asynchronous processes.

The influence of attachment styles on autonomic correlates of perspective-taking

This study examined the effects of attachment styles on physiological responses during a perspective-taking task. Sixty-eight participants were selected according to attachment styles. Physiological responses were assessed using skin conductance responses (SCRs) in the three attachment groups (secure, insecure-anxious and insecure-avoidant) during the presentation of attachment-based pictures (distress, comfort or neutral) in two different perspective-taking conditions: self perspective-taking (i.e. imagine how you would feel in the given situation) or other perspective-taking (i.e. imagine how that person could feel in this situation). In the self perspective-taking condition, insecure-anxious individuals displayed higher SCRs than secure individuals for distress pictures. In the other perspective-taking condition, insecure-anxious individuals showed higher SCRs than secure individuals for comfort pictures. The results also showed a strong negative association between self-reported perspective-taking tendencies and SCRs in secure individuals. The findings suggest that perspective-taking plays an important role in the modulation of physiological responses in reaction to attachment-related pictures, which varies according to attachment styles.

Physical presence of spouse enhances brain-to-brain synchrony in co-parenting couples

Co-parenting spouses who live together remain in close physical proximity to each other and regularly engage in reciprocal social interactions in joint endeavors to coordinate their caregiving. Although bi-parental rearing is a common occurrence in humans, the influence of the physical presence of a co-parenting spouse on parental brain responses remains largely unknown. Synchrony is conceptualized as the matching of behavioral and physiological signals between two individuals. In this study, we examined how the presence of a co-parenting spouse influences brain-to-brain synchrony when attending to salient infant and adult vocalizations. We hypothesized that brain-to-brain synchrony would be greater in the presence of a spousal partner. Functional Near-infrared Spectroscopy (fNIRS) was used on 24 mother-father dyads (N = 48) to measure prefrontal cortical (PFC) activities while they listened to infant and adult vocalizations in two conditions, together (in the same room at the same time) and separately (in different rooms at different times). Couples showed greater synchrony in the together condition; when comparing fNIRS data between true couples and randomly matched controls, this synchronous effect was only seen in true couples, indicating a unique effect of spousal co-regulation toward salient stimuli. Our results indicate that the physical presence of the spouse might establish synchrony in attentional regulation mechanisms toward socially relevant stimuli. This finding holds implications for the role of the co-parenting spouse in influencing social and parental brain mechanisms.