Can group membership modulate the social abilities of autistic people? An intergroup bias in smile perception.

Autistic adults struggle to reliably differentiate genuine and posed smiles. Intergroup bias is a promising factor that may modulate smile discrimination performance, which has been shown in neurotypical adults, and which could highlight ways to make social interactions easier. However, it is not clear whether this bias also exists in autistic people. Thus, the current study aimed to investigate this in autism using a minimal group paradigm. Seventy-five autistic and sixty-one non-autistic adults viewed videos of people making genuine or posed smiles and were informed (falsely) that some of the actors were from an in-group and others were from an out-group. The ability to identify smile authenticity of in-group and out-group members and group identification were assessed. Our results revealed that both groups seemed equally susceptible to ingroup favouritism, rating ingroup members as more genuine, but autistic adults also generally rated smiles as less genuine and were less likely to identify with ingroup members. Autistic adults showed reduced sensitivity to the different smile types but the absence of an intergroup bias in smile discrimination in both groups seems to indicate that membership can only modulate social judgements but not social abilities. These findings suggest a reconsideration of past findings that might have misrepresented the social judgements of autistic people through introducing an outgroup disadvantage, but also a need for tailored support for autistic social differences that emphasizes similarity and inclusion between diverse people.

Brain mechanisms of social signalling in live social interactions with autistic and neurotypical adults.

The simple act of watching another person can change a person's behaviour in subtle but important ways; the individual being watched is now capable of signalling to the watcher, and may use this opportunity to communicate to the watcher. Recent data shows that people will spontaneously imitate more when being watched. Here, we examine the neural and cognitive mechanisms of being watched during spontaneous social imitation in autistic and neurotypical adults using fNIRS brain imaging. Participants (n = 44) took part in a block-moving task where they were instructed only to copy the block sequence which people normally do using a straight low action trajectory. Here, the demonstrator sometimes used an atypical 'high' action trajectory, giving participants the opportunity to spontaneously copy the high trajectory even if this slowed their performance. The confederate who demonstrated each block sequence could watch the participant's actions or close her eyes, giving a factorial design with factors of trajectory (high/low) and watched (watched/unwatched). Throughout the task, brain signals were captured from bilateral temporal/parietal/occipital cortex using fNIRS. We found that all participants performed higher actions when being watched by the confederate than when not being watched, with no differences between autistic and neurotypical participants. The unwatched conditions were associated with higher activity of the right inferior parietal lobule in all participants and also engagement of left STS only in autistic participants. These findings are consistent with the claim that people engage different neural mechanisms when watched and unwatched and that participants with autism may engage additional brain mechanisms to match neurotypical behaviour and compensate for social difficulties. However, further studies will be needed to replicate these results in a larger sample of participants.

Autistic adults benefit from and enjoy learning via social interaction as much as neurotypical adults do.

BACKGROUND: Autistic people show poor processing of social signals (i.e. about the social world). But how do they learn via social interaction? METHODS: 68 neurotypical adults and 60 autistic adults learned about obscure items (e.g. exotic animals) over Zoom (i) in a live video-call with the teacher, (ii) from a recorded learner-teacher interaction video and (iii) from a recorded teacher-alone video. Data were analysed via analysis of variance and multi-level regression models. RESULTS: Live teaching provided the most optimal learning condition, with no difference between groups. Enjoyment was the strongest predictor of learning: both groups enjoyed the live interaction significantly more than other condition and reported similar anxiety levels across conditions. LIMITATIONS: Some of the autistic participants were self-diagnosed-however, further analysis where these participants were excluded showed the same results. Recruiting participants over online platforms may have introduced bias in our sample. Future work should investigate learning in social contexts via diverse sources (e.g. schools). CONCLUSIONS: These findings advocate for a distinction between learning about the social versus learning via the social: cognitive models of autism should be revisited to consider social interaction not just as a puzzle to decode but rather a medium through which people, including neuro-diverse groups, learn about the world around them. Trial registration Part of this work has been pre-registered before data collection https://doi.org/10.17605/OSF.IO/5PGA3.

Are there dedicated neural mechanisms for imitation? A study of grist and mills.

Are there brain regions that are specialized for the execution of imitative actions? We compared two hypotheses of imitation: the mirror neuron system (MNS) hypothesis predicts frontal and parietal engagement which is specific to imitation, while the Grist-Mills hypothesis predicts no difference in brain activation between imitative and matched non-imitative actions. Our delayed imitation fMRI paradigm included two tasks, one where correct performance was defined by a spatial rule and another where it was defined by an item-based rule. For each task, participants could learn a sequence from a video of a human hand performing the task, from a matched "Ghost" condition, or from text instructions. When participants executed actions after seeing the Hand demonstration (compared to Ghost and Text demonstrations), no activation differences occurred in frontal or parietal regions; rather, activation was localized primarily to occipital cortex. This adds to a growing body of evidence which indicates that imitation-specific responses during action execution do not occur in canonical mirror regions, contradicting the mirror neuron system hypothesis. However, activation differences did occur between action execution in the Hand and Ghost conditions outside MNS regions, which runs counter to the Grist-Mills hypothesis. We conclude that researchers should look beyond these hypotheses as well as classical MNS regions to describe the ways in which imitative actions are implemented by the brain.

Face2face: advancing the science of social interaction.

Face-to-face interaction is core to human sociality and its evolution, and provides the environment in which most of human communication occurs. Research into the full complexities that define face-to-face interaction requires a multi-disciplinary, multi-level approach, illuminating from different perspectives how we and other species interact. This special issue showcases a wide range of approaches, bringing together detailed studies of naturalistic social-interactional behaviour with larger scale analyses for generalization, and investigations of socially contextualized cognitive and neural processes that underpin the behaviour we observe. We suggest that this integrative approach will allow us to propel forwards the science of face-to-face interaction by leading us to new paradigms and novel, more ecologically grounded and comprehensive insights into how we interact with one another and with artificial agents, how differences in psychological profiles might affect interaction, and how the capacity to socially interact develops and has evolved in the human and other species. This theme issue makes a first step into this direction, with the aim to break down disciplinary boundaries and emphasizing the value of illuminating the many facets of face-to-face interaction. This article is part of a discussion meeting issue 'Face2face: advancing the science of social interaction'.

Learning from others is good, with others is better: the role of social interaction in human acquisition of new knowledge.

Learning in humans is highly embedded in social interaction: since the very early stages of our lives, we form memories and acquire knowledge about the world from and with others. Yet, within cognitive science and neuroscience, human learning is mainly studied in isolation. The focus of past research in learning has been either exclusively on the learner or (less often) on the teacher, with the primary aim of determining developmental trajectories and/or effective teaching techniques. In fact, social interaction has rarely been explicitly taken as a variable of interest, despite being the medium through which learning occurs, especially in development, but also in adulthood. Here, we review behavioural and neuroimaging research on social human learning, specifically focusing on cognitive models of how we acquire semantic knowledge from and with others, and include both developmental as well as adult work. We then identify potential cognitive mechanisms that support social learning, and their neural correlates. The aim is to outline key new directions for experiments investigating how knowledge is acquired in its ecological niche, i.e. socially, within the framework of the two-person neuroscience approach. This article is part of the theme issue 'Concepts in interaction: social engagement and inner experiences'.

Exploring Theater Neuroscience: Using Wearable Functional Near-infrared Spectroscopy to Measure the Sense of Self and Interpersonal Coordination in Professional Actors.

Ecologically valid research and wearable brain imaging are increasingly important in cognitive neuroscience as they enable researchers to measure neural mechanisms of complex social behaviors in real-world environments. This article presents a proof of principle study that aims to push the limits of what wearable brain imaging can capture and find new ways to explore the neuroscience of acting. Specifically, we focus on how to build an interdisciplinary paradigm to investigate the effects of taking on a role on an actor's sense of self and present methods to quantify interpersonal coordination at different levels (brain, physiology, behavior) as pairs of actors rehearse an extract of a play prepared for live performance. Participants were six actors from Flute Theatre, rehearsing an extract from Shakespeare's A Midsummer Night's Dream. Sense of self was measured in terms of the response of the pFC to hearing one's own name (compared with another person's name). Interpersonal coordination was measured using wavelet coherence analysis of brain signals, heartbeats, breathing, and behavior. Findings show that it is possible to capture an actor's pFC response to their own name and that this response is suppressed when an actor rehearses a segment of the play. In addition, we found that it is possible to measure interpersonal synchrony across three modalities simultaneously. These methods open the way to new studies that can use wearable neuroimaging and hyperscanning to understand the neuroscience of social interaction and the complex social-emotional processes involved in theatrical training and performing theater.

Social signalling as a framework for second-person neuroscience.

Despite the recent increase in second-person neuroscience research, it is still hard to understand which neurocognitive mechanisms underlie real-time social behaviours. Here, we propose that social signalling can help us understand social interactions both at the single- and two-brain level in terms of social signal exchanges between senders and receivers. First, we show how subtle manipulations of being watched provide an important tool to dissect meaningful social signals. We then focus on how social signalling can help us build testable hypotheses for second-person neuroscience with the example of imitation and gaze behaviour. Finally, we suggest that linking neural activity to specific social signals will be key to fully understand the neurocognitive systems engaged during face-to-face interactions.

Social interaction is a catalyst for adult human learning in online contexts.

Human learning is highly social.1-3 Advances in technology have increasingly moved learning online, and the recent coronavirus disease 2019 (COVID-19) pandemic has accelerated this trend. Online learning can vary in terms of how "socially" the material is presented (e.g., live or recorded), but there are limited data on which is most effective, with the majority of studies conducted on children4-8 and inconclusive results on adults.9,10 Here, we examine how young adults (aged 18-35) learn information about unknown objects, systematically varying the social contingency (live versus recorded lecture) and social richness (viewing the teacher's face, hands, or slides) of the learning episodes. Recall was tested immediately and after 1 week. Experiment 1 (n = 24) showed better learning for live presentation and a full view of the teacher (hands and face). Experiment 2 (n = 27; pre-registered) replicated the live-presentation advantage. Both experiments showed an interaction between social contingency and social richness: the presence of social cues affected learning differently depending on whether teaching was interactive or not. Live social interaction with a full view of the teacher's face provided the optimal setting for learning new factual information. However, during observational learning, social cues may be more cognitively demanding11 and/or distracting,12-14 resulting in less learning from rich social information if there is no interactivity. We suggest that being part of a genuine social interaction catalyzes learning, possibly via mechanisms of joint attention,15 common ground,16 or (inter-)active discussion, and as such, interactive learning benefits from rich social settings.17,18.

Effects of being watched on eye gaze and facial displays of typical and autistic individuals during conversation.

LAY ABSTRACT: When we are communicating with other people, we exchange a variety of social signals through eye gaze and facial expressions. However, coordinated exchanges of these social signals can only happen when people involved in the interaction are able to see each other. Although previous studies report that autistic individuals have difficulties in using eye gaze and facial expressions during social interactions, evidence from tasks that involve real face-to-face conversations is scarce and mixed. Here, we investigate how eye gaze and facial expressions of typical and high-functioning autistic individuals are modulated by the belief in being seen by another person, and by being in a face-to-face interaction. Participants were recorded with an eye-tracking and video-camera system while they completed a structured Q&A task with a confederate under three social contexts: pre-recorded video (no belief in being seen, no face-to-face), video-call (belief in being seen, no face-to-face) and face-to-face (belief in being seen and face-to-face). Typical participants gazed less to the confederate and made more facial expressions when they were being watched and when they were speaking. Contrary to our hypotheses, eye gaze and facial expression patterns in autistic participants were overall similar to the typical group. This suggests that high-functioning autistic participants are able to use eye gaze and facial expressions as social signals. Future studies will need to investigate to what extent this reflects spontaneous behaviour or the use of compensation strategies.

Dynamic emotional expressions do not modulate responses to gestures.

The tendency to imitate the actions of others appears to be a fundamental aspect of human social interaction. Emotional expressions are a particularly salient form of social stimuli (Vuilleumier & Schwartz, 2001) but their relationship to imitative behaviour is currently unclear. In this paper we report the results of five studies which investigated the effect of a target's dynamic emotional stimuli on participants' tendency to respond compatibly to the target's actions. Experiment one examined the effect of dynamic emotional expressions on the automatic imitation of opening and closing hand movements. Experiment two used the same basic paradigm but added gaze direction as an additional factor. Experiment three investigated the effect of dynamic emotional expressions on compatibility responses to handshakes. Experiment four investigated whether dynamic emotional expressions modulated response to valenced social gestures. Finally, experiment five compared the effects of dynamic and static emotional expressions on participants' automatic imitation of finger lifting. Across all five studies we reliably elicited a compatibility effect however, none of the studies found a significant modulating effect of emotional expression. This null effect was also supported by a random effects meta-analysis and a series of Bayesian t-tests. Nevertheless, these results must be caveated by the fact that our studies had limited power to detect effect sizes below d = 0.4. We conclude by situating our findings within the literature, suggesting that the effect of emotional expressions on automatic imitation is, at best, minimal.

Hyperscanning: Beyond the Hype.

Hyperscanning-the recording of brain activity from multiple individuals-can be hard to interpret. This paper shows how integrating behavioral data and mutual prediction models into hyperscanning studies can lead to advances in embodied social neuroscience.

Facial and neural mechanisms during interactive disclosure of biographical information.

Pairs of participants mutually communicated (or not) biographical information to each other. By combining simultaneous eye-tracking, face-tracking and functional near-infrared spectroscopy, we examined how this mutual sharing of information modulates social signalling and brain activity. When biographical information was disclosed, participants directed more eye gaze to the face of the partner and presented more facial displays. We also found that spontaneous production and observation of facial displays was associated with activity in the left SMG and right dlPFC/IFG, respectively. Moreover, mutual information-sharing increased activity in bilateral TPJ and left dlPFC, as well as cross-brain synchrony between right TPJ and left dlPFC. This suggests that a complex long-range mechanism is recruited during information-sharing. These multimodal findings support the second-person neuroscience hypothesis, which postulates that communicative interactions activate additional neurocognitive mechanisms to those engaged in non-interactive situations. They further advance our understanding of which neurocognitive mechanisms underlie communicative interactions.

Distinct neural correlates of social and object reward seeking motivation.

The "Choose-a-Movie-CAM" is an established task to quantify the motivation for seeking social rewards. It allows participants to directly assess both the stimulus value and the effort required to obtain it. In the present study, we aimed to identify the neural mechanisms of such cost-benefit decision-making. To this end, functional Magnetic Resonance Imaging data were collected from 24 typical adults while they completed the CAM task. We partly replicated the results from our previous behavioural studies showing that typical adults prefer social over object stimuli and low effort over higher effort stimuli but found no interaction between the two. Results from neuroimaging data suggest that there are distinct neural correlates for social and object preferences. The precuneus and medial orbitofrontal cortex, two key areas involved in social processing are engaged when participants make a social choice. Areas of the ventral and dorsal stream pathways associated with object recognition are engaged when making an object choice. These activations can be seen during the decision phase even before the rewards have been consumed, indicating a transfer the hedonic properties of social stimuli to its cues. We also found that the left insula and bilateral clusters in the inferior occipital gyrus and the inferior parietal lobule were recruited for increasing effort investment. We discuss limitations and implications of this study which reveals the distinct neural correlates for social and object rewards, using a robust behavioural measure of social motivation.

Are You on My Wavelength? Interpersonal Coordination in Dyadic Conversations.

Conversation between two people involves subtle nonverbal coordination in addition to speech. However, the precise parameters and timing of this coordination remain unclear, which limits our ability to theorize about the neural and cognitive mechanisms of social coordination. In particular, it is unclear if conversation is dominated by synchronization (with no time lag), rapid and reactive mimicry (with lags under 1 s) or traditionally observed mimicry (with several seconds lag), each of which demands a different neural mechanism. Here we describe data from high-resolution motion capture of the head movements of pairs of participants (n = 31 dyads) engaged in structured conversations. In a pre-registered analysis pathway, we calculated the wavelet coherence of head motion within dyads as a measure of their nonverbal coordination and report two novel results. First, low-frequency coherence (0.2-1.1 Hz) is consistent with traditional observations of mimicry, and modeling shows this behavior is generated by a mechanism with a constant 600 ms lag between leader and follower. This is in line with rapid reactive (rather than predictive or memory-driven) models of mimicry behavior, and could be implemented in mirror neuron systems. Second, we find an unexpected pattern of lower-than-chance coherence between participants, or hypo-coherence, at high frequencies (2.6-6.5 Hz). Exploratory analyses show that this systematic decoupling is driven by fast nodding from the listening member of the dyad, and may be a newly identified social signal. These results provide a step towards the quantification of real-world human behavior in high resolution and provide new insights into the mechanisms of social coordination.

Brief Report: Autistic Adults Assign Less Weight to Affective Cues When Judging Others' Ambiguous Emotional States.

Understanding other people's emotional states involves integrating multiple sources of information, such as someone's smile (affective cue) with our knowledge that they have passed an exam (situational cue). We explored whether autistic adults display differences in how they integrate these cues by showing participants videos of students receiving their exams results. Our results suggest autistic adults generally perform as neurotypical participants when identifying and integrating affective and situational cues. It was only in certain unfamiliar and ambiguous social situations that autistic adults assigned less weight to affective cues compared to situational cues when judging other people's emotional states.

The neural basis of shared preference learning.

During our daily lives, we often learn about the similarity of the traits and preferences of others to our own and use that information during our social interactions. However, it is unclear how the brain represents similarity between the self and others. One possible mechanism is to track similarity to oneself regardless of the identity of the other (Similarity account); an alternative is to track each other person in terms of consistency of their choice similarity with respect to the choices they have made before (consistency account). Our study combined functional Magnetic Resonance Imaging (fMRI) and computational modelling of reinforcement learning (RL) to investigate the neural processes that underlie learning about preference similarity. Participants chose which of two pieces of artwork they preferred and saw the choices of one agent who usually shared their preference and another agent who usually did not. We modelled neural activation with RL models based on the similarity and consistency accounts. Our results showed that activity in brain areas linked to reward and social cognition followed the consistency account. Our findings suggest that impressions of other people can be calculated in a person-specific manner, which assumes that each individual behaves consistently with their past choices.

Effects of being watched on self-referential processing, self-awareness and prosocial behaviour.

Reputation management theory suggests that our behaviour changes in the presence of others to signal good reputation (audience effect). However, the specific cognitive mechanisms by which being watched triggers these changes are poorly understood. Here we test the hypothesis that these changes happen because the belief in being watched increases self-referential processing. We used a novel deceptive video-conference paradigm, where participants believe a video-clip is (or is not) a live feed of a confederate watching them. Participants completed four tasks measuring self-referential processing, prosocial behaviour and self-awareness under these two belief settings. Although the belief manipulation and self-referential effect task were effective, there were no changes on self-referential processing between the two settings, nor on prosocial behaviour and self-awareness. Based on previous evidence and these findings, we propose that further research on the role of the self, social context and personality traits will help elucidating the mechanisms underlying audience effects.

The Role of Eye Gaze During Natural Social Interactions in Typical and Autistic People.

Social interactions involve complex exchanges of a variety of social signals, such as gaze, facial expressions, speech and gestures. Focusing on the dual function of eye gaze, this review explores how the presence of an audience, communicative purpose and temporal dynamics of gaze allow interacting partners to achieve successful communication. First, we focus on how being watched modulates social cognition and behavior. We then show that the study of interpersonal gaze processing, particularly gaze temporal dynamics, can provide valuable understanding of social behavior in real interactions. We propose that the Interpersonal Gaze Processing model, which combines both sensing and signaling functions of eye gaze, provides a framework to make sense of gaze patterns in live interactions. Finally, we discuss how autistic individuals process the belief in being watched and interpersonal dynamics of gaze, and suggest that systematic manipulation of factors modulating gaze signaling can reveal which aspects of social eye gaze are challenging in autism.

Adults imitate to send a social signal.

Humans frequently imitate each other's actions with high fidelity, and different reasons have been proposed for why they do so. Here we test the hypothesis that imitation can act as a social signal, with imitation occurring with greater fidelity when a participant is being watched. In a preregistered study, 30 pairs of naïve participants played an augmented-reality game involving moving blocks in space. We compared imitation fidelity between trials where the leader watched the followers' action, and trials where the leader did not watch. Followers imitated the trajectory height demonstrated by the leader, and critically, the strength of this correlation was greater in trials where the follower knew the leader was watching them. This suggests that followers spontaneously used imitation as a social signal in a nonverbal interaction task, supporting socio-communicative hypotheses of imitation.