Human social behavior is characterized by a dynamic interplay between inclusion and exclusion. While positive social interaction affects neural, endocrine and physiological synchrony, social rejection can further modify these processes, leading to distinct cognitive and emotional consequences and possibly clinical symptoms. Thus, understanding the mechanisms underlying these experiences is critical for advancing social neuroscience and preventing mental disorders. This symposium brings together cutting-edge research investigating the neural and physiological underpinnings of social exclusion and interaction by integrating findings from diverse experimental paradigms. Using diverse methods such as fMRI hyperscanning, physiological synchronization and sympathetic and endocrine analyses, these presentations provide new insights into how social connection and rejection influence brain function, autonomic and endocrine responses, and interpersonal dynamics in healthy and clinical samples.

Linn Kühl will talk about the link between emotional abuse in childhood and rejection sensitivity in later life. Nele Reinsberg will present data from two replication studies looking at social exclusion, including the potential protective effect of smartphones. Katja Wingenfeld will then demonstrate findings on the effects of social exclusion in patients with borderline personality disorder. Julia Koch will uncover the neural bases of interpersonal social processes including the dynamics of aggression. In the final presentation, Nina Volkmer will present the effects of social exclusion on physiological synchrony in a conformity paradigm.

In the discussion, we will consider theoretical and methodological advances, implications for mental health and social behavior, and future directions for interdisciplinary research on social exclusion and interaction.

Social inclusion and belonging is a basic human need, and social exclusion may be especially challenging to individuals with enhanced sensitivity to social rejection. Emotional maltreatment during childhood is considered as one predisposing factor for rejection sensitivity. In two studies, we tested the hypothesis that in particular emotional maltreatment (emotional abuse and neglect) compared to other maltreatment subtypes relate to rejection sensitivity in emerging adults. Rejection sensitivity was measured as a trait as well as a state in response to social exclusion in an experimental design.

In study 1, 311 emerging adults (18-25 years) participated in a retrospective cross-sectional assessment. Here, we investigated whether intensities of childhood emotional abuse and neglect have unique associations with trait rejection sensitivity, when considering other maltreatment subtypes (emotional, sexual and physical abuse, emotional and physical neglect). In study 2, 78 emerging adults participated in an experiment (O-Cam paradigm) which included the experience of social exclusion. Here, we examined whether childhood emotional maltreatment moderated the response to social exclusion in terms of need depletion, sadness and anger (vs. inclusion).

The results of study 1 indicate that emotional abuse and neglect have unique associations with rejection sensitivity. The results of study 2 shows significant effects for emotional abuse.

We conclude that childhood emotional abuse may relate to rejection sensitivity expressed in enhanced responses to social exclusion in young adulthood. Enhanced rejection sensitivity may be considered as one mechanism how childhood emotional maltreatment predisposes individuals to interpersonal and mental health problems.

Young adults have increasingly reported experiences of loneliness during the recent COVID-19 pandemic. Loneliness and social exclusion can have profound effects on mental and physical health and can be associated with depression, migraines or back pain. Neuroimaging results show that identical brain regions are activated during social exclusion and physical pain. Phones can act as a buffer, exerting a protective effect during social exclusion. Reliable and credible research is essential for the development of effective prevention and intervention strategies.

Within this talk, results of two conceptual replication studies will be discussed. Both studies utilized experimental paradigms, albeit with distinct approaches, to induce social exclusion in young students in Germany.

Study 1 aimed to replicate the research of Eisenberger et al. (2003) by using the Cyberball paradigm, a virtual ball tossing game, to investigate the relationship between social exclusion and pain. With data collection ongoing, questionnaire data from n = 35 participants were collected, heart rate (HR) and heart rate variability (HRV) assessment as physiological indicators are in preparation.

Study 2 sought to replicate the findings of Hunter et al. (2018), using the Yale Interpersonal Stressor, focusing on exploring the buffering effect of phones in N = 84 participants. In addition to subjective responses, HR and HRV were measured.

Subjective and physiological data will be discussed. Preliminary data show that both paradigms successfully induced social exclusion.

Both studies provide valuable insights into social exclusion of young adults and its implications on prevention efforts, which emphasizes the importance of replication studies.

Compared to healthy individuals, patients with Borderline personality disorder (BPD) showed a blunted cortisol response and an enhanced reactivity of the autonomous nervous system after psychosocial stress induced with the Trier Social Stress Test (TSST). Additionally, they reported reduced emotional empathy, while healthy individuals typically react to stress with heightened empathy and prosocial behavior.

We aimed to investigate whether social exclusion is involved in these alterations. This is plausible, as social exclusion is one of the most unpleasant components of the TSST, which individuals with BPD are especially sensitive to.

We randomized women with BPD and healthy women to an exclusion or an overinclusion condition of the virtual ball game Cyberball. Cortisol, heart rate variability (HRV), and perceived stress were measured and participants underwent measurements of social cognition.

Patients with BPD showed higher need threat in both Cyberball conditions (overinclusion and exclusion) compared to HC. This difference was more pronounced after exclusion. On a physiological level, no changes in cortisol were seen but vagal responses differed between patients and controls. Implications of the presented results will be discussed.

Investigation of the neural bases of interpersonal social processes has been advanced by second‐person neuroscience approaches that employ dyadic hyperscanning. We will present data from a hyperscanning study that investigates aggression dynamics in a sibling sample performing various interaction tasks (including audio recording). Behavioral and neural responses were recorded simultaneously, allowing us to examine both within-subject dynamics and intra-dyad interactions. Our findings provide insight into the neural mechanisms underlying interpersonal conflict by linking patterns of aggression with specific neural activity across interacting individuals.

Background: Social interactions have a profound impact onr our health. While studies have shown how negative social situations (e.g., exclusion) manifest themselves on the intraindividual physiological level, the accompanying interpersonal dynamics are less well elucidated. Therefore, the current study investigates whether dissimilarity of opinion in a group affects physiological synchrony during a discussion task. Methods: We assessed N=50 participants (62% female) in a naturalistic conformity paradigm. Interested participants were initially screened regarding their opinions across a variety of socio-political topics (e.g., speed limit on highways). Eligible participants were then allocated into groups of 4-5 so that all but one member shared a similar opinion regarding a specific topic. At the beginning of the session, participants were asked to publicly position themselves on the topic in question, defend their position, and participate in a group discussion. Subsequently, participants’ position regarding the topic was once again voiced publicly. The entire session was accompanied by an electrocardiogram (ECG) recording. We used multilevel models to investigate effects of opinion difference (combined across all votings) on dyadic heart rate variability (HRV) synchrony (cross-wavelet power calculated from ECG data) within high frequency. Results: Preliminary results indicate that the relation between opinion difference and HRV synchrony is dependent on the specific frequency range. Interestingly, greater opinion difference is associated with increased HRV synchronization within the 0.125-0.25 frequency range, while no relation could be found within the 0.25-0.5 frequency range. Discussion: These results suggest distinct interpersonal dynamics on the physiological level at specific frequencies.