Social interaction is fundamental in daily life. While research shows that top-down influences affect social interactions, the level at which this takes place remains unclear. For example, studies investigating the influence of group membership on sensorimotor simulation, a core low-level mechanism of social interaction, have resulted in mixed evidence. We aimed to reconcile and extend these findings to offer a unified account of the effects of group membership on sensorimotor simulation processes. We hypothesized that group membership affects sensorimotor simulation of others’ actions only when embodied prediction is necessary. In two experiments, where participants observed hand movements congruent or incongruent with their own, we showed that racial group membership only modulated the congruency effect during response preparation when embodied prediction of the other’s movements was present. These results provide insights into how racial group membership, a salient visual inter-individual difference, shapes low-level mechanisms that are fundamental to our social life.

Objective Previous research has indicated that patients with Anorexia Nervosa (AN) exhibit specific eye movement changes, identified through eye tracking sensor technology. These changes have been proposed as potential digital biomarkers and endophenotypes for early diagnosis and preventive clinical interventions. This study aims to explore whether these eye movement changes are also present in individuals with subclinical eating disorder (ED) symptomatology compared to control participants. Method The study recruited participants using convenience sampling and employed the Eating Disorder Examination Questionnaire for initial screening. The sample was subsequently divided into two groups: individuals exhibiting subclinical ED symptomatology and control participants. Both groups performed various tasks, including a fixation task, prosaccade/antisaccade task, and memory-guided task. Alongside these tasks, anxiety and premorbid intelligence were measured as potential confounding variables. The data were analyzed through means comparison and exploratory Pearson’s correlations. Results No significant differences were found between the two groups in the three eye tracking tasks. Discussion The findings suggest that the observed changes in previous research might be more related to the clinical state of the illness rather than a putative trait. Implications for the applicability of eye movement changes as early biomarkers and endophenotypes for EDs in subclinical populations are discussed. Further research is needed to validate these findings and understand their implications for preventive diagnostics. Registration https://jeatdisord.biomedcentral.com/articles/10.1186/s40337-022-00573-2

Mental body representations are malleable and can be influenced by auditory cues. In the "Footsteps illusion," real-time alterations of walking sounds simulate those produced by heavier or lighter bodies, affecting perceptions of body weight, speed, and gender traits, and triggering emotional, behavioral, and physiological changes. While body illusions are known to affect social attitudes, less is known about how social factors influence body perception malleability. We investigated whether social support networks modulate this malleability using the "Footsteps illusion," given the social relevance of body weight. A total of 105 participants experienced three footstep sound conditions (heavier, lighter and control). We collected demographic, behavioral, physiological, and subjective data, along with body image and eating disorder questionnaires. Results showed that larger social support networks correlated with higher body image satisfaction and fewer eating disorder symptoms. Notably, the illusion had a stronger effect on those with smaller social networks, highlighting the moderating role of social support.

Empathic accuracy, the ability to accurately understand other people’s emotions, is a complex social cognitive skill that is often impaired in schizophrenia and this impairment is associated with poor functional outcomes. Intranasally administered oxytocin, a neuropeptide implicated in social behavior, is thought to improve empathic accuracy for individuals with schizophrenia. However, early experiences related to caregiving may shape the oxytocinergic system and influence individual responses to oxytocin administration. Using a cross-over, double-blind, placebo-controlled design coupled with fMRI, the current study investigated whether administration of oxytocin improves empathic accuracy in schizophrenia compared to a matched placebo, and the moderating role of early maternal care. Results revealed that, compared to controls, individuals with schizophrenia had lower empathic accuracy and recruited a sparser pattern of neural activation to achieve empathic accuracy. Oxytocin administration was not associated with improved empathic accuracy for either group. However, in both groups, individuals reporting higher maternal care demonstrated the greatest improvements in empathic accuracy with oxytocin administration, accompanied by decreased activity in the right dorsolateral prefrontal cortex, a region implicated in selective attention to socioemotional stimuli. Findings highlight the importance of examining individual differences in responses to oxytocin administration and suggest that early social experiences influence later responses to oxytocin administration.

Online hostility, including cyberbullying, hate speech, and trolling, has become a pervasive issue on social media and affecting users’ mental health. Our work explores the potential of gamification to mitigate the negative impacts of online hostility. Specifically, we investigate how gamification influences brain activity and user behavior in response to hostile interactions on social networks. Our proposed method uses EEG technology to develop personalized interventions that promote emotional regulation and reduce aggressive behavior in social media. We designed a theoretical framework that integrates EEG analysis with gamified interventions, enabling real-time monitoring and modification of users’ emotional and cognitive responses to online hostility. This framework provides insights into the neurocognitive effects of online hostility and opens the way for innovative solutions to building healthier social network environments. A preliminary simulation was conducted as a proof-of-concept to model brain responses under conditions of baseline (regular interaction), exposure to online hostility, and gamified interventions. The simulation illustrates how gamification can regulate brain activity, promoting a calmer mental state and mitigating the adverse effects of online hostility. This paper details our theoretical framework, presents the simulation results, and discusses the implications.

Background Recent research indicates that patients with anorexia (AN) show specific eye movement abnormalities such as shorter prosaccade latencies, more saccade inhibition errors, and increased rate of saccadic intrusions compared to participants without AN. However, it remains unknown whether these abnormal eye movement patterns, which may serve as potential biomarkers and endophenotypes for an early diagnosis and preventive clinical treatments, start to manifest also in people with subclinical eating disorders (ED) symptomatology. Therefore, we propose a protocol for an exploratory experimental study to investigate whether participants with subclinical ED symptomatology and control participants differ in their performance on several eye movement tasks. Methods The sample will be recruited through convenience sampling. The Eating Disorder Examination Questionnaire will be administered as a screening tool to split the sample into participants with subclinical ED symptomatology and control participants. A fixation task, prosaccade/antisaccade task, and memory-guided task will be administered to both groups. Additionally, we will measure anxiety and premorbid intelligence as confounding variables. Means comparison, exploratory Pearson's correlations and discriminant analysis will be performed. Discussion This study will be the first to elucidate the presence of specific eye movement abnormalities in participants with subclinical ED symptomatology. The results may open opportunities for developing novel diagnostic tools/therapies being helpful to the EDs research community and allied fields.

Experience of childhood abuse (CA) impairs complex social functioning in children; however, much less is known about its effects on basic sociocognitive processes and even fewer studies have investigated these in adult survivors. Using two behavioral tasks, this study investigated spontaneous theory of mind (ToM) and imitative behavior in 41 women with CA and 26 unaffected comparison (UC) women. In the spontaneous ToM task, UCs showed a larger ToM index than CAs, indicating more facilitation by knowledge of another's false belief. In the imitation-inhibition task, CAs experienced less interference than UCs when observing another's incongruent movements. After controlling for depression, differences in ToM became marginally significant, yet remained highly significant for inhibiting imitative behavior. The findings suggest CA survivors have altered perspective-taking and are less influenced by others' perspectives, potentially due to changes in self-other distinction. Clinical implications regarding therapeutic practice with survivors of CA are discussed.

Own-perceived body matching – the ability to match one’s own body with an observed body – is a difficult task for both general and clinical populations. Thus far, however, own-perceived body matching has been investigated in situations that are incongruent with how we are used to experience and perceive our body in daily life. In the current study, we aimed to examine own-perceived body matching in a context that more closely resembles real life. More specifically, we investigated the effects of body movement dynamics and clothing cues on own-perceived body matching. We asked participants to match their own body with an externally perceived body that was a 3D-generated avatar based on participants’ real bodies, fitted with a computer-generated dress. This perceived body was (1) either static (non-walking avatar) or dynamic (walking avatar), (2) either bigger, smaller, or the same size as participants’ own body size, and (3) fitted with a dress with a size either bigger, smaller, or the same as participants’ own dress size. Our results suggest that movement dynamics cues did not improve the accuracy of own-perceived body matching, but that confidence about dress fit was higher for dynamic avatars, and that the difference between dynamic and static avatars was dependent on participants’ self-esteem. Furthermore, when participants were asked to rate the observed body in reference to how they wanted to represent themselves to others, dynamic avatars were rated lower than static avatars for the biggest-sized bodies only, possibly reflecting the influence of movement cues on amplifying socio-cultural stereotypes. Finally, while smaller body/dress sizes were systematically rated higher than bigger body/dress sizes for several self-report items, the interplay between body and dress size played an important role in participants’ self-report as well. Thus, while our research suggests that movement and garment dynamics, allowing for realistic, concrete situations that are reminiscent of daily life, influence own-body perception, these cues did not lead to an improvement in accuracy. These findings provide important insights for research exploring (own-) body perception and bodily self-awareness, with practical (e.g., development of online avatars) and clinical (e.g., anorexia nervosa and body dysmorphic disorder) implications.

A mismatch exists between people's mental representations of their own body and their real body measurements, which may impact general well-being and health. We investigated whether this mismatch is reduced when contextualizing body size estimation in a real-life scenario. Using a reverse correlation paradigm, we constructed unbiased, data-driven visual depictions of participants' implicit body representations. Across three conditions-own abstract, ideal, and own concrete body-participants selected the body that looked most like their own, like the body they would like to have, or like the body they would use for online shopping. In the own concrete condition only, we found a significant correlation between perceived and real hip width, suggesting that the perceived/real body match only exists when body size estimation takes place in a practical context, although the negative correlation indicated inaccurate estimation. Further, participants who underestimated their body size or who had more negative attitudes towards their body weight showed a positive correlation between perceived and real body size in the own abstract condition. Finally, our results indicated that different body areas were implicated in the different conditions. These findings suggest that implicit body representations depend on situational and individual differences, which has clinical and practical implications.

People are generally unable to accurately determine their own body measurements and to translate this knowledge to identifying a model/avatar that best represents their own body. This inability has not only been related to health problems (e.g. anorexia nervosa), but has important practical implications as well (e.g. online retail). Here we aimed to investigate the influence of three basic visual features-face presence, amount of viewpoints, and observed model size-on the perceived match between own and observed models' bodies and on attitudes towards these models. Models were real-life models (Experiment 1) or avatar models based on participants' own bodies (Experiment 2). Results in both experiments showed a strong effect of model size, irrespective of participants' own body measurements. When models were randomly presented one by one, participants gave significantly higher ratings to smaller- compared to bigger-sized models. The reverse was true, however, when participants observed and compared models freely, suggesting that the mode of presentation affected participants' judgments. Limited evidence was found for an effect of facial presence or amount of viewpoints. These results add evidence to research on visual features affecting the ability to match observed bodies with own body image, which has biological, clinical, and practical implications.

Negative symptoms are core contributors to vocational and social deficits in schizophrenia (SZ). Available antipsychotic medications typically fail to reduce these symptoms. The neurohormone oxytocin (OT) is a promising treatment for negative symptoms, given its role in complex social behaviors mediated by the amygdala. In sample 1, we used a double-blind, placebo-controlled, crossover design to test the effects of a single dose of intranasal OT on amygdala resting-state functional connectivity (rsFC) in SZ (n = 22) and healthy controls (HC, n = 24) using a whole-brain corrected approach: we identified regions for which OT modulated SZ amygdala rsFC, assessed whether OT-modulated circuits were abnormal in SZ relative to HC on placebo, and evaluated whether connectivity on placebo and OT-induced connectivity changes correlated with baseline negative symptoms in SZ. Given our modest sample size, we used a second SZ (n = 183) and HC (n = 178) sample to replicate any symptom correlations. In sample 1, OT increased rsFC between the amygdala and left middle temporal gyrus, superior temporal sulcus, and angular gyrus (MTG/STS/AngG) in SZ compared to HC. Further, SZ had hypo-connectivity in this circuit compared to HC on placebo. More severe negative symptoms correlated with less amygdala-to-left-MTG/STS/AngG connectivity on placebo and with greater OT-induced connectivity increases. In sample 2, we replicated the correlation between amygdala-left-MTG/STS/AngG hypo-connectivity and negative symptoms, finding a specific association with expressive negative symptoms. These data suggest intranasal OT can normalize functional connectivity in an amygdala-to-left-MTG/STS/AngG circuit that contributes to negative symptoms in SZ.

Deficits in emotion perception (the ability to infer others’ emotions accurately) can occur as a result of neurodegeneration. It remains unclear how different neurodegenerative diseases affect different forms of emotion perception. The present study compares performance on a dynamic tracking task of emotion perception (where participants track the changing valence of a film character’s emotions) with performance on an emotion category labeling task (where participants label specific emotions portrayed by film characters) across seven diagnostic groups (N = 178) including Alzheimer’s disease (AD), behavioral variant frontotemporal dementia (bvFTD), semantic variant primary progressive aphasia (svPPA), non-fluent variant primary progressive aphasia (nfvPPA), progressive supranuclear palsy (PSP), corticobasal syndrome and healthy controls. Consistent with hypotheses, compared to controls, the bvFTD group was impaired on both tasks. The svPPA group was impaired on the emotion labeling task, whereas the nfvPPA, PSP and AD groups were impaired on the dynamic tracking task. Smaller volumes in bilateral frontal and left insular regions were associated with worse labeling, whereas smaller volumes in bilateral medial frontal, temporal and right insular regions were associated with worse tracking. Findings suggest labeling and tracking facets of emotion perception are differentially affected across neurodegenerative diseases due to their unique neuroanatomical correlates.

INTRODUCTION:Mimicking movements of others makes both the imitating and imitated partners feel closer. Oxytocin may increase focus on others and has been shown to increase automatic imitation in healthy controls (HC). However, this has not been replicated, and oxytocin's effects on automatic imitation have not been demonstrated in clinical populations. This study attempts to replicate effects on HC and examine effects on people with comorbid posttraumatic stress disorder and alcohol use disorder (PTSD-AUD).METHODS:Fifty-four males with PTSD-AUD and 43 male HC received three intranasal treatment conditions (placebo, oxytocin 20 International Units (IU), and oxytocin 40 IU) in a randomized order, across three separate testing days, as part of a double-blind, crossover parent study. At 135 min post-administration, each performed the imitation-inhibition task, which quantifies automatic imitation as the congruency effect (CE). After exclusions, the final analyzed data set included 49 participants with PTSD-AUD and 38 HC.RESULTS:In HC, oxytocin 20 IU demonstrated a statistically significant increase in CE, and 40 IU showed a trend-level increase. In PTSD-AUD, oxytocin did not significantly increase CE. Post-hoc analysis showed the PTSD-AUD group had higher CE than HC on placebo visits.DISCUSSION:Our data suggest PTSD-AUD is associated with higher automatic imitation than HC in the absence of oxytocin administration. We successfully replicated findings that oxytocin increases automatic imitation in HC. This demonstrates an unconscious motor effect induced by oxytocin, likely relevant to more complex forms of imitative movements, which have the potential to improve social connection. We did not find a significant effect of oxytocin on automatic imitation in PTSD-AUD. Future research should examine imitation in both sexes, at peak oxytocin levels, and on increasingly complex forms of imitation.

BACKGROUND:Aberrant sensitivity to social reward may be an important contributor to abnormal social behavior that is a core feature of schizophrenia. The neuropeptide oxytocin impacts the salience of social information across species, but its effect on social reward in schizophrenia is unknown.METHODS:We used a competitive economic game and computational modeling to examine behavioral dynamics and oxytocin effects on sensitivity to social reward among 39 men with schizophrenia and 54 matched healthy controls. In a randomized, double-blind study, participants received one dose of oxytocin (40 IU) or placebo and completed a 35-trial Auction Game that quantifies preferences for monetary v. social reward. We analyzed bidding behavior using multilevel linear mixed models and reinforcement learning models.RESULTS:Bidding was motivated by preferences for both monetary and social reward in both groups, but bidding dynamics differed: patients initially overbid less compared to controls, and across trials, controls decreased their bids while patients did not. Oxytocin administration was associated with sustained overbidding across trials, particularly in patients. This drug effect was driven by a stronger preference for winning the auction, regardless of monetary consequences. Learning rate and response variability did not differ between groups or drug condition, suggesting that differences in bidding derive primarily from differences in the subjective value of social rewards.CONCLUSIONS:Our findings suggest that schizophrenia is associated with diminished motivation for social reward that may be increased by oxytocin administration.

Social cognitive impairments, including theory of mind (ToM), in schizophrenia more strongly predict functional outcomes than psychotic symptoms or nonsocial cognitive deficits. Despite their clinical importance, current medications do not improve these deficits. The current study investigated the hypothesis that oxytocin, a neuropeptide implicated in social behavior, would normalize neural abnormalities in schizophrenia during ToM, and that this normalization would correlate improvement in ToM behavior. In this cross-over, double-blind, and placebo-controlled functional magnetic resonance imaging study, a single dose of 40 IU of oxytocin was administered via nasal spray to male individuals with a schizophrenia spectrum disorder (schizophrenia and schizoaffective disorder, n = 23) and healthy controls (n = 25). Participants completed two ToM tasks in the scanner, the False Belief and Person Description tasks. During both tasks, on placebo day, schizophrenia was associated with reduced accuracy, hypo-activity in the right temporo-parietal junction (rTPJ; extended into the posterior superior temporal sulcus), and hypo-connectivity between the rTPJ and medial prefrontal cortex (mPFC) compared to healthy controls. Oxytocin, relative to placebo, significantly increased accuracy and rTPJ activation for ToM but not control stories in schizophrenia. Furthermore, a significant positive correlation was found between oxytocin induced increases in rTPJ activity and accuracy, indicating that oxytocin improved rTPJ activity in schizophrenia predicted behavioral improvement. Oxytocin also significantly improved connectivity between rTPJ and mPFC in schizophrenia. These findings suggest that rTPJ activity during ToM might be a potential neural target for the treatment of social cognitive deficits in schizophrenia.

Autism spectrum disorder is a neurodevelopmental disorder that is associated with problems in empathy. Recent research suggests that impaired control over self–other overlap based on motor representations in individuals with autism spectrum disorder might underlie these difficulties. In order to investigate the relationship of self–other distinction and empathy for pain in high-functioning autism and matched controls, we manipulated self–other distinction by using a paradigm in which participants are either imitated or not by a hand on a computer screen. A strong pain stimulus is then inflicted on the observed hand. Behavioral and physiological results in this study showed that overall affective responses while watching pain movies were the same in adults with high-functioning autism as in controls. Furthermore, controls showed higher affective responding after being imitated during the whole experiment, replicating previous studies. Adults with high-functioning autism, however, showed increased empathic responses over time after being imitated. Further exploratory analyses suggested that while affective responding was initially lower after being imitated compared to not being imitated, affective responding in the latter part of the experiment was higher after being imitated. These results shed new light on empathic abilities in high-functioning autism and on the role of control over self–other representational sharing.

Automatic imitation is the finding that movement execution is facilitated by compatible and impeded by incompatible observed movements. In the past 15 years, automatic imitation has been studied to understand the relation between perception and action in social interaction. Although research on this topic started in cognitive science, interest quickly spread to related disciplines such as social psychology, clinical psychology. and neuroscience. However, important theoretical questions have remained unanswered. Therefore, in the present meta-analysis, we evaluated seven key questions on automatic imitation. The results, based on 161 studies containing 226 experiments, revealed an overall effect size of g(z) = 0.95, 95% CI [0.88, 1.02]. Moderator analyses identified automatic imitation as a flexible, largely automatic process that is driven by movement and effector compatibility, but is also influenced by spatial compatibility. Automatic imitation was found to be stronger for forced choice tasks than for simple response tasks, for human agents than for nonhuman agents, and for goalless actions than for goal-directed actions. However, it was not modulated by more subtle factors such as animacy beliefs, motion profiles, or visual perspective. Finally, there was no evidence for a relation between automatic imitation and either empathy or autism. Among other things. these findings point toward actor-imitator similarity as a crucial modulator of automatic imitation and challenge the view that imitative tendencies are an indicator of social functioning. The current meta-analysis has important theoretical implications and sheds light on longstanding controversies in the literature on automatic imitation and related domains.

Decision-making in dynamic social contexts requires multiple cognitive abilities, including mentalizing, that are frequently impaired in schizophrenia. Oxytocin administration has been shown to improve mentalizing in schizophrenia, suggesting therapeutic potential.

Although social situations regularly involve multiple persons acting together, research on the mirror neuron system has focused on situations in which a single agent is observed. Therefore, the goal of the current study was to explore the role of the mirror mechanism in situations involving multiple agents. Specifically, we used transcranial magnetic stimulation (TMS) to investigate whether mirror activation is modulated by the number of observed agents. Based on group contagion research, we hypothesized that multiple agents would provide a stronger trigger to the motor system and would therefore produce a stronger mirror response than a single agent. Participants observed movements performed by a single hand or by two hands while TMS was applied to the primary motor cortex. The results confirmed that activation in the motor system was stronger for two hands. This suggests that input to the motor system increases as the number of agents grows. Relating back to group contagion, our study suggests that groups may be more contagious simply because their actions resonate louder. Given that the mirror mechanism has been linked to a variety of social skills, our findings additionally have important implications for the understanding of social interaction at the group level.

A large body of research has provided evidence for the idea that individuals simulate the actions of others in their motor system. However, this research has focused almost exclusively on dyadic situations, hence ignoring the fact that social situations often require that the actions of multiple persons are simulated simultaneously. In the current study, we addressed this issue by means of a widely used automatic imitation task. In Experiment 1, it is shown that individuals automatically imitate the actions of 2 agents at the same time. More specifically, the results indicate that 2 identical observed movements produce a stronger imitation effect, whereas 2 different observed movements produce 2 opposite imitation effects that cancel each other out. In Experiment 2, it is shown that the effects obtained in Experiment 1 cannot be explained in terms of attentional capture. Instead, the results point toward an explanation in terms of ideomotor theory. The finding that observers simultaneously represent the actions of multiple agents in their motor system allows for a better understanding of social interaction beyond the dyad.