Gender-specific modulation of neural mechanisms underlying social reward processing by Autism Quotient

Anticipatory and consummatory neural correlates of monetary and music rewarding stimuli

Most of the literature on the neural bases of human reward and punishment processing has used monetary gains and losses, but less is known about the neurophysiological mechanisms underlying the anticipation and consumption of other types of rewarding stimuli. In the present study, EEG was recorded from 19 participants who completed a modified version of the Monetary Incentive Delay (MID) task. During the task, cues providing information about potential future outcomes were presented to the participants. Then, they had to respond rapidly to a target stimulus to win money or listening to pleasant music, or to avoid losing money or listening to unpleasant music. Results revealed similar responses for monetary and music cues, with increased activity for cues indicating potential gains compared to losses. However, differences emerged in the outcome phase between money and music. Monetary outcomes showed an interaction between the type of the cue and the outcome in the Feedback Related Negativity and Fb-P3 ERPs and increased theta activity increased for negative feedbacks. In contrast, music outcomes showed significant interactions in the Fb-P3 and theta activities. These findings suggest similar neurophysiological mechanisms in processing cues for potential positive or negative outcomes in these two types of stimuli.

Appetitive conditioning with pornographic stimuli elicits stronger activation in reward regions than monetary and gaming-related stimuli

Appetitive conditioning plays an important role in the development and maintenance of pornography-use and gaming disorders. It is assumed that primary and secondary reinforcers are involved in these processes. Despite the common use of pornography and gaming in the general population appetitive conditioning processes in this context are still not well studied. This study aims to compare appetitive conditioning processes using primary (pornographic) and secondary (monetary and gaming-related) rewards as unconditioned stimuli (UCS) in the general population. Additionally, it investigates the conditioning processes with gaming-related stimuli as this type of UCS was not used in previous studies. Thirty-one subjects participated in a differential conditioning procedure in which four geometric symbols were paired with either pornographic, monetary, or gaming-related rewards or with nothing to become conditioned stimuli (CS + porn, CS + game, CS + money, and CS-) in an functional magnetic resonance imaging study. We observed elevated arousal and valence ratings as well as skin conductance responses for each CS+ condition compared to the CS-. On the neural level, we found activations during the presentation of the CS + porn in the bilateral nucleus accumbens, right medial orbitofrontal cortex, and the right ventral anterior cingulate cortex compared to the CS-, but no significant activations during CS + money and CS + game compared to the CS-. These results indicate that different processes emerge depending on whether primary and secondary rewards are presented separately or together in the same experimental paradigm. Additionally, monetary and gaming-related stimuli seem to have a lower appetitive value than pornographic rewards.

Sex differences in the rapid detection of neutral faces associated with emotional value

BACKGROUND

Rapid detection of faces with emotional meaning is essential for understanding the emotions of others, possibly promoting successful interpersonal relationships. Although few studies have examined sex differences in the ability to detect emotional faces, it remains unclear whether faces with emotional meaning capture the attention of females and males differently, because emotional faces have visual saliency that modulates visual attention. To overcome this issue, we tested the rapid detection of the neutral faces associated with and without learned emotional value, which are all regarded as free from visual saliency. We examined sex differences in the rapid detection of the neutral female and male faces associated with emotional value.

METHODS

First, young adult female and male participants completed an associative learning task in which neutral faces were associated with either monetary rewards, monetary punishments, or no monetary outcomes, such that the neutral faces acquired positive, negative, and no emotional value, respectively. Then, they engaged in a visual search task in which previously learned neutral faces were presented as discrepant faces among newly presented neutral distractor faces. During the visual search task, the participants were required to rapidly identify discrepant faces.

RESULTS

Female and male participants exhibited comparable learning abilities. The visual search results demonstrated that female participants achieved rapid detection of neutral faces associated with emotional value irrespective of the sex of the faces presented, whereas male participants showed this ability only for male faces.

CONCLUSIONS

Our results demonstrated that sex differences in the ability to rapidly detect neutral faces with emotional value were modulated by the sex of those faces. The results suggest greater sensitivity to faces with emotional significance in females, which might enrich interpersonal communication, regardless of sex.

Anticipating social feedback involves basal forebrain and mesolimbic functional connectivity

The mesolimbic system and basal forebrain (BF) are implicated in processing rewards and punishment, but their interplay and functional properties of subregions with respect to future social outcomes remain unclear. Therefore, this study investigated regional responses and interregional functional connectivity of the lateral (l), medial (m), and ventral (v) Substantia Nigra (SN), Nucleus Accumbens (NAcc), Nucleus basalis of Meynert (NBM), and Medial Septum/Diagonal Band (MS/DB) during reward and punishment anticipation in a social incentive delay task with neutral, positive, and negative feedback using high-resolution fMRI (1.5mm³). Neuroimaging data (n=36 healthy humans) of the anticipation phase was analyzed using mass-univariate, functional connectivity, and multivariate-pattern analysis. As expected, participants responded faster when anticipating positive and negative compared to neutral social feedback. At the neural level, anticipating social information engaged valence-related and valence-unrelated functional connectivity patterns involving the BF and mesolimbic areas. Precisely, valence-related connectivity between the lSN and NBM was associated with anticipating neutral social feedback, while connectivity between the vSN and NBM was associated with anticipating positive social feedback. A more complex pattern was observed for anticipating negative social feedback, including connectivity between the lSN and MS/DB, lSN and NAcc, as well as mSN and NAcc. To conclude, behavioral responses are modulated by the possibility to obtain positive and avoid negative social feedback. The neural processing of feedback anticipation relies on functional connectivity patterns between the BF and mesolimbic areas associated with the emotional valence of the social information. As such, our findings give novel insights into the underlying neural processes of social information processing.

Altered neural mechanism of social reward anticipation in individuals with schizophrenia and social anhedonia

Altered social reward anticipation could be found in schizophrenia (SCZ) patients and individuals with high levels of social anhedonia (SA). However, few research investigated the putative neural processing for altered social reward anticipation in these populations on the SCZ spectrum. This study aimed to examine the underlying neural mechanisms of social reward anticipation in these populations. Twenty-three SCZ patients and 17 healthy controls (HC), 37 SA individuals and 50 respective HCs completed the Social Incentive Delay (SID) imaging task while they were undertaking MRI brain scans. We used the group contrast to examine the alterations of BOLD activation and functional connectivity (FC, psychophysiological interactions analysis). We then characterized the beta-series social brain network (SBN) based on the meta-analysis results from NeuroSynth and examined their prediction effects on real-life social network (SN) characteristics using the partial least squared regression analysis. The results showed that SCZ patients exhibited hypo-activation of the left medial frontal gyrus and the negative FCs with the left parietal regions, while individuals with SA showed the hyper-activation of the left middle frontal gyrus when anticipating social reward. For the beta-series SBNs, SCZ patients had strengthened cerebellum-temporal FCs, while SA individuals had strengthened left frontal regions FCs. However, such FCs of the SBN failed to predict the real-life SN characteristics. These preliminary findings suggested that SCZ patients and SA individuals appear to exhibit altered neural processing for social reward anticipation, and such neural activities showed a weakened association with real-life SN characteristics.

The Effects of Anhedonia in Social Context

Purpose of Review

Anhedonia is a transdiagnostic symptom comprising reduced subjective reward or pleasure. Anhedonia influences subjective anticipation and in-the-moment experiences. This review draws together affective learning and engagement evidence for anhedonia affecting subjective experiences of social environments.

Recent Findings

While social engagement is diminished consistently, subjective appraisals of social contexts vary across different mental health disorders. Low positive affect during social experiences or stimuli is reported in PTSD, mood, schizophrenia, and anxiety disorders. Diminished neural reward networks underpin the anticipation of social experiences in ADHD, schizophrenia spectrum, and autistic spectrum disorders. Multiple theories exist to explain how anhedonia might interfere with social environments.

Summary

Anhedonia is a barrier to engagement, motivation, and enjoyment of social contexts. While many studies characterize experiences during social contexts, learning theories provide the most promise for developing targeted interventions.

Basal ganglia lateralization in different types of reward

Reward processing is a fundamental human activity. The basal ganglia are recognized for their role in reward processes; however, specific roles of the different nuclei (e.g., nucleus accumbens, caudate, putamen and globus pallidus) remain unclear. Using quantitative meta-analyses we assessed whole-brain and basal ganglia specific contributions to money, erotic, and food reward processing. We analyzed data from 190 fMRI studies which reported stereotaxic coordinates of whole-brain, within-group results from healthy adult participants. Results showed concordance in overlapping and distinct cortical and sub-cortical brain regions as a function of reward type. Common to all reward types was concordance in basal ganglia nuclei, with distinct differences in hemispheric dominance and spatial extent in response to the different reward types. Food reward processing favored the right hemisphere; erotic rewards favored the right lateral globus pallidus and left caudate body. Money rewards engaged the basal ganglia bilaterally including its most anterior part, nucleus accumbens. We conclude by proposing a model of common reward processing in the basal ganglia and separate models for money, erotic, and food rewards.

Coping style predicts sense of security and mediates the relationship between autistic traits and social anxiety: Moderation by a polymorphism of the FKBP5 gene

The mechanism underlying the relationship between autistic traits and social anxiety still remains unknown. It is therefore necessary to investigate potential psychological and biological mechanisms. A total of 2695 college students were samples for this research during 2017-2018. The assessed variables included demographic characteristics and measures of autistic traits, sense of security, coping styles, and social anxiety. Blood samples were collected from which DNA was extracted. Regression analysis indicated that autistic traits and negative coping were positively associated with social anxiety; furthermore, positive coping, interpersonal security, and sense of control were negatively associated with social anxiety. Further analyses demonstrated that the relationship between autistic traits and social anxiety was mediated by coping styles (both positive coping and negative coping) and sense of security (both interpersonal security and sense of control), and coping style predicted the sense of security. The FK506 binding protein 5 (FKBP5) gene rs3800373 moderated the association between autistic traits and social anxiety. The present study is the first to demonstrate that both coping style and sense of security play an intermediate role between autistic traits and social anxiety in a sample of Chinese college students; moreover, the FKBP5 gene moderates this association between autistic traits and social anxiety.

Mapping social reward and punishment processing in the human brain: A voxel-based meta-analysis of neuroimaging findings using the social incentive delay task

Social rewards or punishments motivate human learning and behaviour, and alterations in the brain circuits involved in the processing of these stimuli have been linked with several neuropsychiatric disorders. However, questions still remain about the exact neural substrates implicated in social reward and punishment processing. Here, we conducted four Anisotropic Effect Size Signed Differential Mapping voxel-based meta-analyses of fMRI studies investigating the neural correlates of the anticipation and receipt of social rewards and punishments using the Social Incentive Delay task. We found that the anticipation of both social rewards and social punishment avoidance recruits a wide network of areas including the basal ganglia, the midbrain, the dorsal anterior cingulate cortex, the supplementary motor area, the anterior insula, the occipital gyrus and other frontal, temporal, parietal and cerebellar regions not captured in previous coordinate-based meta-analysis. We identified decreases in the BOLD signal during the anticipation of both social reward and punishment avoidance in regions of the default-mode network that were missed in individual studies likely due to a lack of power. Receipt of social rewards engaged a robust network of brain regions including the ventromedial frontal and orbitofrontal cortices, the anterior cingulate cortex, the amygdala, the hippocampus, the occipital cortex and the brainstem, but not the basal ganglia. Receipt of social punishments increased the BOLD signal in the orbitofrontal cortex, superior and inferior frontal gyri, lateral occipital cortex and the insula. In contrast to the receipt of social rewards, we also observed a decrease in the BOLD signal in the basal ganglia in response to the receipt of social punishments. Our results provide a better understanding of the brain circuitry involved in the processing of social rewards and punishment. Furthermore, they can inform hypotheses regarding brain areas where disruption in activity may be associated with dysfunctional social incentive processing during disease.

Atypical social reward anticipation as a transdiagnostic characteristic of psychopathology: A meta-analytic review and critical evaluation of current evidence

Several psychopathologies (e.g. schizophrenia spectrum conditions, autism spectrum disorders) are characterised by atypical interpersonal and social behaviour, and there is increasing evidence to suggest this atypical social behaviour is related to adjusted behavioural and neural anticipation of social rewards. This review brings together social reward anticipation research in psychopathology (k = 42) and examines the extent to which atypical social reward anticipation is a transdiagnostic characteristic. Meta-analyses of anticipatory reaction times revealed that, in comparison to healthy controls, attention-deficit/hyperactivity disorder, autism spectrum disorder, and schizophrenia spectrum conditions are associated with significantly reduced behavioural anticipation of social rewards. The pooled meta-analysis of anticipatory reaction times found that the full clinical sample demonstrated significant social reward hypoanticipation in comparison to the healthy control group with a medium effect size. A narrative synthesis of meta-analytically ineligible behavioural data, self-report data, and neuroimaging studies complemented the results of the meta-analysis, but also indicated that bipolar disorder, eating disorders, and sexual addiction disorders may be associated with social reward hyperanticipation. The evaluation of existing evidence suggests that future research should better account for factors that affect reward anticipation (e.g. gender, psychotropic medication) and highlights the importance of using stimuli other than happy faces as social rewards.

Neural Dynamic Responses of Monetary and Social Reward Processes in Adolescents

Adolescence is an essential developmental period characterized by reward-related processes. The current study investigated the development of monetary and social reward processes in adolescents compared with that in children and adults; furthermore, it assessed whether adolescents had different levels of sensitivity to various types of rewards. Two adapted incentive delay tasks were employed for each participant, and event-related potentials (ERPs) were recorded. The behavioral results showed that both monetary and social rewards could motivate response speed, and participants were more accurate under the monetary reward condition than under the social reward condition. The behavioral performances of individuals increased with age. For the ERP data, the cue-P3, target-P2, target-P3 and feedback-related negativity (FRN) components were investigated to identify reward motivation, emotional arousal, attention allocation and feedback processing. Children and adolescents showed higher motivation (larger cue-P3) to rewards than adults. Adolescents showed larger emotional responses to rewards; that is, they had larger target-P2 amplitudes than adults and shorter target-P2 latencies than children. Children showed stronger emotional reactivity for monetary rewards than for social rewards. All age groups had stronger attentional control (larger target-P3) under the monetary reward condition than under the social reward condition. The present study sheds light on the neurodevelopment of reward processes in children, adolescents and adults and shows that various reward process stages demonstrate different age-related and reward-type-related characteristics.

Love is analogous to money in human brain: Coordinate-based and functional connectivity meta-analyses of social and monetary reward anticipation

Both social and material rewards play a crucial role in daily life and function as strong incentives for various goal-directed behaviors. However, it remains unclear whether the incentive effects of social and material reward are supported by common or distinct neural circuits. Here, we have addressed this issue by quantitatively synthesizing and comparing neural signatures underlying social (21 contrasts, 207 foci, 696 subjects) and monetary (94 contrasts, 1083 foci, 2060 subjects) reward anticipation. We demonstrated that social and monetary reward anticipation engaged a common neural circuit consisting of the ventral tegmental area, ventral striatum, anterior insula, and supplementary motor area, which are intensively connected during both task and resting states. Functional decoding findings indicate that this generic neural pathway mediates positive value, motivational relevance, and action preparation during reward anticipation, which together motivate individuals to prepare well for the response to the upcoming target. Our findings support the common neural currency hypothesis by providing the first meta-analytic evidence to quantitatively show the common involvement of brain regions in both social and material reward anticipation.

Gradual acquisition of visuospatial associative memory representations via the dorsal precuneus

Activation of parietal cortex structures like the precuneus is commonly observed during explicit memory retrieval, but the role of parietal cortices in encoding has only recently been appreciated and is still poorly understood. Considering the importance of the precuneus in human visual attention and imagery, we aimed to assess a potential role for the precuneus in the encoding of visuospatial representations into long-term memory. We therefore investigated the acquisition of constant versus repeatedly shuffled configurations of icons on background images over five subsequent days in 32 young, healthy volunteers. Functional magnetic resonance imaging was conducted on Days 1, 2, and 5, and persistent memory traces were assessed by a delayed memory test after another 5 days. Constant compared to shuffled configurations were associated with significant improvement of position recognition from Day 1 to 5 and better delayed memory performance. Bilateral dorsal precuneus activations separated constant from shuffled configurations from Day 2 onward, and coactivation of the precuneus and hippocampus dissociated recognized and forgotten configurations, irrespective of condition. Furthermore, learning of constant configurations elicited increased functional coupling of the precuneus with dorsal and ventral visual stream structures. Our results identify the precuneus as a key brain structure in the acquisition of detailed visuospatial information by orchestrating a parieto-occipito-temporal network.

Sex differences in default mode and dorsal attention network engagement

Focusing on sex differences is necessary to fully understand basic neurobiological processes such as the engagement of large-scale brain networks involved in attention. Prior work suggests that women show enhanced attention during tasks of reward/punishment relative to men. Yet, sex differences in the engagement of neural networks sub serving internal and external focus has been unexplored in regard to reward and punishment. Using data from a large sample (n = 190) of healthy participants from the Human Connectome Project, we investigated sex differences in default mode network (DMN), dorsal attention network (DAN), and frontal parietal network (FPN) activation during exposure to reward and punishment. To determine if sex differences are specific to valenced stimuli, we analyzed network activation during working memory. Results indicate that, relative to men, women have increased suppression of the DMN and greater activation of the DAN during exposure to reward and punishment. Given the relative roles of these networks in internal (DMN) and external (DAN) attention, this pattern of activation suggests that women have enhanced external attention to reward and punishment. In contrast, there were no sex differences in network activation during working memory, indicating that this sex difference is specific to the processing of reward and punishment. These findings suggest a neurobiological explanation for prior work showing women have greater sensitivity to reward/punishment and are more prone to psychiatric disorders characterized by enhanced attention to such stimuli. Furthermore, given the large sample from the Human Connectome Project, the current findings provide general implications for the study of sex as a biological variable in investigation of reward processes.

Behavioral and Neural Manifestations of Reward Memory in Carriers of Low-Expressing versus High-Expressing Genetic Variants of the Dopamine D2 Receptor

Dopamine is critically important in the neural manifestation of motivated behavior, and alterations in the human dopaminergic system have been implicated in the etiology of motivation-related psychiatric disorders, most prominently addiction. Patients with chronic addiction exhibit reduced dopamine D2 receptor (DRD2) availability in the striatum, and the DRD2 TaqIA (rs1800497) and C957T (rs6277) genetic polymorphisms have previously been linked to individual differences in striatal dopamine metabolism and clinical risk for alcohol and nicotine dependence. Here, we investigated the hypothesis that the variants of these polymorphisms would show increased reward-related memory formation, which has previously been shown to jointly engage the mesolimbic dopaminergic system and the hippocampus, as a potential intermediate phenotype for addiction memory. To this end, we performed functional magnetic resonance imaging (fMRI) in 62 young, healthy individuals genotyped for DRD2 TaqIA and C957T variants. Participants performed an incentive delay task, followed by a recognition memory task 24 h later. We observed effects of both genotypes on the overall recognition performance with carriers of low-expressing variants, namely TaqIA A1 carriers and C957T C homozygotes, showing better performance than the other genotype groups. In addition to the better memory performance, C957T C homozygotes also exhibited a response bias for cues predicting monetary reward. At the neural level, the C957T polymorphism was associated with a genotype-related modulation of right hippocampal and striatal fMRI responses predictive of subsequent recognition confidence for reward-predicting items. Our results indicate that genetic variations associated with DRD2 expression affect explicit memory, specifically for rewarded stimuli. We suggest that the relatively better memory for rewarded stimuli in carriers of low-expressing DRD2 variants may reflect an intermediate phenotype of addiction memory.

Monetary, Food, and Social Rewards Induce Similar Pavlovian-to-Instrumental Transfer Effects

Multiple types of reward, such as money, food or social approval, are capable of driving behavior. However, most previous investigations have only focused on one of these reward classes in isolation, as such it is not clear whether different reward classes have a unique influence on instrumental responding or whether the subjective value of the reward, rather than the reward type per se, is most important in driving behavior. Here, we investigate behavior using a well-established reward paradigm, Pavlovian-to-instrumental transfer (PIT), and three different reward types: monetary, food and social rewards. The subjective value of each reward type was matched using a modified Becker-DeGroot-Marschak (BDM) auction where subjective reward value was expressed through physical effort using a bimanual grip force task. We measured the influence of reward-associated stimuli on how participants distributed forces between hands when reaching a target effort range on the screen bimanually and on how much time participants spent in this target range. Participants spent significantly more time in the target range (15% ± 2% maximal voluntary contraction) when a stimulus was presented that was associated with a reward used during instrumental conditioning or Pavlovian conditioning compared to a stimulus associated with a neutral outcome (i.e., general PIT). The strength of the PIT effect was modulated by subjective value (i.e., individuals who showed a stronger PIT effect rated the value of rewards more highly), but not by reward type, demonstrating that stimuli of all reward types were able to act as appetitive reinforcers and influenced instrumental responding, when matched to the same subjective reward value. This is the first demonstration that individually matched monetary, food and social rewards are equally effective as appetitive reinforcers in PIT. These findings strengthen the hypotheses that the subjective value is crucial for how much reward-associated stimuli influence behavior.

A negative relationship between ventral striatal loss anticipation response and impulsivity in borderline personality disorder

Patients with borderline personality disorder (BPD) frequently exhibit impulsive behavior, and self-reported impulsivity is typically higher in BPD patients when compared to healthy controls. Previous functional neuroimaging studies have suggested a link between impulsivity, the ventral striatal response to reward anticipation, and prediction errors. Here we investigated the striatal neural response to monetary gain and loss anticipation and their relationship with impulsivity in 21 female BPD patients and 23 age-matched female healthy controls using functional magnetic resonance imaging (fMRI). Participants performed a delayed monetary incentive task in which three categories of objects predicted a potential gain, loss, or neutral outcome. Impulsivity was assessed using the Barratt Impulsiveness Scale (BIS-11). Compared to healthy controls, BPD patients exhibited significantly reduced fMRI responses of the ventral striatum/nucleus accumbens (VS/NAcc) to both reward-predicting and loss-predicting cues. BIS-11 scores showed a significant positive correlation with the VS/NAcc reward anticipation responses in healthy controls, and this correlation, while also nominally positive, failed to reach significance in BPD patients. BPD patients, on the other hand, exhibited a significantly negative correlation between ventral striatal loss anticipation responses and BIS-11 scores, whereas this correlation was significantly positive in healthy controls. Our results suggest that patients with BPD show attenuated anticipation responses in the VS/NAcc and, furthermore, that higher impulsivity in BPD patients might be related to impaired prediction of aversive outcomes.

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We investigated striatal reward and loss anticipation in patients with Borderline Personality Disorder (BPD) and controls

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BPD patients relative to controls exhibited reduced ventral striatal / nucleus accumbens (VS/NAcc) anticipation responses

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In healthy controls, VS responses to gains and losses correlated positively with impulsivity

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BPD patients exhibited a negative correlation between loss responses and impulsivity.

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Our results suggest that impulsivity in BPD patients may in part result from impaired anticipation of aversive outcomes.

Diffusion of responsibility attenuates altruistic punishment: A functional magnetic resonance imaging effective connectivity study

Humans altruistically punish violators of social norms to enforce cooperation and pro-social behaviors. However, such altruistic behaviors diminish when others are present, due to a diffusion of responsibility. We investigated the neural signatures underlying the modulations of diffusion of responsibility on altruistic punishment, conjoining a third-party punishment task with event-related functional magnetic resonance imaging and multivariate Granger causality mapping. In our study, participants acted as impartial third-party decision-makers and decided how to punish norm violations under two different social contexts: alone (i.e., full responsibility) or in the presence of putative other third-party decision makers (i.e., diffused responsibility). Our behavioral results demonstrated that the diffusion of responsibility served as a mediator of context-dependent punishment. In the presence of putative others, participants who felt less responsible also punished less severely in response to norm violations. Our neural results revealed that underlying this behavioral effect was a network of interconnected brain regions. For unfair relative to fair splits, the presence of others led to attenuated responses in brain regions implicated in signaling norm violations (e.g., AI) and to increased responses in brain regions implicated in calculating values of norm violations (e.g., vmPFC, precuneus) and mentalizing about others (dmPFC). The dmPFC acted as the driver of the punishment network, modulating target regions, such as AI, vmPFC, and precuneus, to adjust altruistic punishment behavior. Our results uncovered the neural basis of the influence of diffusion of responsibility on altruistic punishment and highlighted the role of the mentalizing network in this important phenomenon. Hum Brain Mapp 37:663-677, 2016. © 2015 Wiley Periodicals, Inc.

Interaction matters: A perceived social partner alters the neural processing of human speech

Mounting evidence suggests that social interaction changes how communicative behaviors (e.g., spoken language, gaze) are processed, but the precise neural bases by which social-interactive context may alter communication remain unknown. Various perspectives suggest that live interactions are more rewarding, more attention-grabbing, or require increased mentalizing-thinking about the thoughts of others. Dissociating between these possibilities is difficult because most extant neuroimaging paradigms examining social interaction have not directly compared live paradigms to conventional "offline" (or recorded) paradigms. We developed a novel fMRI paradigm to assess whether and how an interactive context changes the processing of speech matched in content and vocal characteristics. Participants listened to short vignettes--which contained no reference to people or mental states--believing that some vignettes were prerecorded and that others were presented over a real-time audio-feed by a live social partner. In actuality, all speech was prerecorded. Simply believing that speech was live increased activation in each participant's own mentalizing regions, defined using a functional localizer. Contrasting live to recorded speech did not reveal significant differences in attention or reward regions. Further, higher levels of autistic-like traits were associated with altered neural specialization for live interaction. These results suggest that humans engage in ongoing mentalizing about social partners, even when such mentalizing is not explicitly required, illustrating how social context shapes social cognition. Understanding communication in social context has important implications for typical and atypical social processing, especially for disorders like autism where social difficulties are more acute in live interaction.