Social attention and the ventromedial prefrontal cortex

Activation network mapping for integration of heterogeneous fMRI findings

Functional neuroimaging techniques have been widely used to probe the neural substrates of facial emotion processing in healthy people. However, findings are largely inconsistent across studies. Here, we introduce a new technique termed activation network mapping to examine whether heterogeneous functional magnetic resonance imaging findings localize to a common network for emotion processing. First, using the existing method of activation likelihood estimation meta-analysis, we showed that individual-brain-based reproducibility was low across studies. Second, using activation network mapping, we found that network-based reproducibility across these same studies was higher. Validation analysis indicated that the activation network mapping-localized network aligned with stimulation sites, structural abnormalities and brain lesions that disrupt facial emotion processing. Finally, we verified the generality of the activation network mapping technique by applying it to another cognitive process, that is, rumination. Activation network mapping may potentially be broadly applicable to localize brain networks of cognitive functions.

A neurobiological perspective on social influence: Serotonin and social adaptation

Humans are inherently social beings. Being suggestible to each other's expectations enables pro-social skills that are crucial for social learning and adaptation. Despite its high relevance for psychiatry, the neurobiological mechanisms underlying social adaptation are still not well understood. This review therefore provides a conceptual framework covering various distinct mechanisms underlying social adaptation and explores the neuropharmacology - in particular the role of the serotonin (5-HT) system - modulating these mechanisms. This article therefore reviews empirical results on social influence processing and reconciles them with recent findings from psychedelic research on social processing to elucidate neurobiological and neuropharmacological underpinnings of social adaptation. Various computational, neurobiological, and neurochemical processes are involved in distinct mechanisms underlying social adaptation such as the multisensory process of social information integration that is crucial for the forming of self-representation and representations of social norms. This is again associated with self- and other-perception during social interactions as well as value-based decision making that guides our behaviour in daily interactions. We highlight the critical role of 5-HT in these processes and suggest that 5-HT can facilitate social learning and may represent an important target for treating psychiatric disorders characterized by impairments in social functioning. This framework also has important implications for psychedelic-assisted therapy as well as for the development of novel treatment approaches and future research directions.

A comparison of stages of attention for social and nonsocial stimuli in schizophrenia: An ERP study

Social motivation disturbances have been long observed in people with schizophrenia, yet the underlying components that drive these impairments remain unclear. Social attention is one component of social motivation and involves stages of attentional orienting, alerting/sustained attention, and executive control. It is not known at which stage the breakdown in social attention occurs in schizophrenia. The present study examined the allocation of social versus nonsocial attention at multiple stages of processing using event related potential (ERP) components. Electroencephalography from 36 outpatients with schizophrenia and 20 healthy participants was recorded during a dot probe task while viewing social/nonsocial stimuli that assessed: (1) orienting (indexed by the N1pc), (2) sustained attention (Contingent Negative Variation, [CNV]), and (3) executive control of attention during target evaluation (P300). Additionally, we analyzed correlations between the ERPs and participants' reaction times (RT) to the targets. Schizophrenia participants oriented their attention equally to social and nonsocial stimuli (N1pc), showed greater sustained attention to social than nonsocial stimuli (i.e., larger CNV), and exerted greater executive control on social trials (i.e., larger P300) than nonsocial trials, similarly to healthy participants. However, schizophrenia participants showed diminished overall sustained attention (blunted CNV) during the task, compared with healthy participants. Furthermore, greater sustained attention (larger CNV) and greater executive control (larger P300) were associated with improved behavioral performance (faster RTs) for healthy participants, but not schizophrenia participants. Together, these findings suggest there is impaired sustained attention for both social and nonsocial stimuli in schizophrenia, and their attention may not correspond with their behavior.

Cooperation with partners of differing social experience: An fNIRS-based hyperscanning study

Previous studies have shown the brain synchronization of all team members while completing a collaborative task. Moreover, this effect is influenced by a team's compositional elements, such as gender (opposite or same) or relationships (i.e., friends, lovers, or strangers) among team members. However, whether interpersonal brain synchronization (IBS) is affected by team members' experience, as well as the temporal dynamics of such brain synchronization, remains to be investigated. In the current study, we combined behavioral methods and functional near-infrared spectroscopy-based hyperscanning to examine the effect of member experience on team cooperation by an adopted continuous joint drawing task with 21 student-student dyads (S-S dyads) and 22 teacher-student dyads (T-S dyads). The results revealed that team members with differing experiences (T-S dyads) perform better than those with similar ones (S-S dyads). Moreover, we observed IBS in the left frontopolar region (channel 11). However, we did not observe significant changes of the task-related IBS across time. Besides, IBS was negatively correlated with the participants' behavioral performance. Our findings demonstrate the importance of social experience in teamwork in the real world and suggest a possible mechanism for cooperation from a temporal and spatial perspective.

Behavioral and brain synchronization differences between expert and novice teachers when collaborating with students

Differences in behavior and neural mechanisms between expert and novice teachers when collaborating with students are poorly understood. This study investigated whether expert teachers do better in collaborating with students than novice teachers and explored the neural basis of such differences. Novice teacher and student (NT-S) dyads and expert teacher and student (ET-S) dyads were recruited to complete an interactive task consisting of a cooperation and an independent condition. During the experiment, neural activity in the prefrontal cortex of the participants was recorded with functional near-infrared spectroscopy. The results show higher accuracy for the ET-S dyads than the NT-S dyads in the cooperation condition; however, no difference was found in the independent condition. Increased interpersonal brain synchronization (IBS) was detected in the left dorsolateral prefrontal cortex of participants in ET-S dyads, but not in NT-S dyads in the cooperation condition. Moreover, an interaction effect of dyad type and conditions on IBS was observed, revealing IBS was stronger in ET-S dyads than in NT-S dyads. In ET-S dyads, IBS was positively correlated with the teachers' perspective-taking ability and accuracy. These findings suggest that expert teachers collaborate better with students than novice teachers, and IBS might be the neural marker for this difference.

Interplay between prior knowledge and communication mode on teaching effectiveness: Interpersonal neural synchronization as a neural marker

Teacher-student interaction allows students to combine prior knowledge with new information to develop new knowledge. It is widely understood that both communication mode and students' knowledge state contribute to the teaching effectiveness (i.e., higher students' scores), but the nature of the interplay of these factors and the underlying neural mechanism remain unknown. In the current study, we manipulated the communication modes (face-to-face [FTF] communication mode/computer-mediated communication [CMC] mode) and prior knowledge states (with vs. without) when teacher-student dyads participated in a teaching task. Using functional near-infrared spectroscopy, the brain activities of both the teacher and student in the dyads were recorded simultaneously. After teaching, perceived teacher-student interaction and teaching effectiveness were assessed. The behavioral results demonstrated that, during teaching with prior knowledge, FTF communication improved students' academic performance, as compared with CMC. Conversely, no such effect was found for teaching without prior knowledge. Accordingly, higher task-related interpersonal neural synchronization (INS) in the left prefrontal cortex (PFC) was found in the FTF teaching condition with prior knowledge. Such INS mediated the relationship between perceived interaction and students' test scores. Furthermore, the cumulative INS in the left PFC could predict the teaching effectiveness early in the teaching process (around 25-35 s into the teaching task) only in FTF teaching with prior knowledge. These findings provide insight into how the interplay between the communication mode and students' knowledge state affects teaching effectiveness. Moreover, our findings suggest that INS could be a possible neuromarker for dynamic evaluation of teacher-student interaction and teaching effectiveness.

Neural mechanisms for selectively tuning in to the target speaker in a naturalistic noisy situation

The neural mechanism for selectively tuning in to a target speaker while tuning out the others in a multi-speaker situation (i.e., the cocktail-party effect) remains elusive. Here we addressed this issue by measuring brain activity simultaneously from a listener and from multiple speakers while they were involved in naturalistic conversations. Results consistently show selectively enhanced interpersonal neural synchronization (INS) between the listener and the attended speaker at left temporal–parietal junction, compared with that between the listener and the unattended speaker across different multi-speaker situations. Moreover, INS increases significantly prior to the occurrence of verbal responses, and even when the listener’s brain activity precedes that of the speaker. The INS increase is independent of brain-to-speech synchronization in both the anatomical location and frequency range. These findings suggest that INS underlies the selective process in a multi-speaker situation through neural predictions at the content level but not the sensory level of speech.

When many people are speaking, e.g. at a party, we can selectively attend to just one speaker. Here, using ‘hyperscanning’, the authors show that interpersonal neural synchronization is selectively increased between a listener and the attended speaker, compared to between the listener and an unattended speaker.

Structural connections support emotional connections: Uncinate Fasciculus microstructure is related to the ability to decode facial emotion expressions

The Uncinate Fasciculus (UF) is an association fibre tract connecting regions in the frontal and anterior temporal lobes. UF disruption is seen in several disorders associated with impaired social behaviour, but its functional role is unclear. Here we set out to test the hypothesis that the UF is important for facial expression processing, an ability fundamental to adaptive social behaviour. In two separate experiments in healthy adults, we used high-angular resolution diffusion-weighted imaging (HARDI) and constrained spherical deconvolution (CSD) tractography to virtually dissect the UF, plus a control tract (the corticospinal tract (CST)), and quantify, via fractional anisotropy (FA), individual differences in tract microstructure. In Experiment 1, participants completed the Reading the Mind in the Eyes Task (RMET), a well-validated assay of facial expression decoding. In Experiment 2, a different set of participants completed the RMET, plus an odd-emotion-out task of facial emotion discrimination. In both experiments, participants also completed a control odd-identity-out facial identity discrimination task. In Experiment 1, FA of the right-, but not the left-hemisphere, UF was significantly correlated with performance on the RMET task, specifically for emotional, but not neutral expressions. UF FA was not significantly correlated with facial identity discrimination performance. In Experiment 2, FA of the right-, but not left-hemisphere, UF was again significantly correlated with performance on emotional items from the RMET, together with performance on the facial emotion discrimination task. Again, no significant association was found between UF FA and facial identity discrimination performance. Our findings highlight the contribution of right-hemisphere UF microstructure to inter-individual variability in the ability to decode facial emotion expressions, and may explain why disruption of this pathway affects social behaviour.

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We studied white matter microstructure correlates of facial emotion decoding skills.

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Focused on the role of a key limbic tract, the Uncinate Fasciculus (UF).

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Right UF microstructure linked to facial expression decoding skills.

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UF microstructure not related to facial identity discrimination skills.

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Right UF has a distinct role in the processing of facial expressions of emotion.

'Emotional Intelligence': Lessons from Lesions

'Emotional intelligence' (EI) is one of the most highly used psychological terms in popular nomenclature, yet its construct, divergent, and predictive validities are contentiously debated. Despite this debate, the EI construct is composed of a set of emotional abilities - recognizing emotional states in the self and others, using emotions to guide thought and behavior, understanding how emotions shape behavior, and emotion regulation - that undoubtedly influence important social and personal outcomes. In this review, evidence from human lesion studies is reviewed in order to provide insight into the necessary brain regions for each of these core emotional abilities. Critically, we consider how this neuropsychological evidence might help to guide efforts to define and measure EI.

Top-Down Control of Serotonin Systems by the Prefrontal Cortex: A Path toward Restored Socioemotional Function in Depression

Social withdrawal, increased threat perception, and exaggerated reassurance seeking behaviors are prominent interpersonal symptoms in major depressive disorder (MDD). Altered serotonin (5-HT) systems and corticolimbic dysconnectivity have long been suspected to contribute to these symptomatic facets; however, the underlying circuits and intrinsic cellular mechanisms that control 5-HT output during socioemotional interactions remain poorly understood. We review literature that implicates a direct pathway between the ventromedial prefrontal cortex (vmPFC) and dorsal raphe nucleus (DRN) in the adaptive and pathological control of social approach-avoidance behaviors. Imaging and neuromodulation during approach-avoidance tasks in humans point to the cortical control of brainstem circuits as an essential regulator of socioemotional decisions and actions. Parallel rodent studies using viral-based connectomics and optogenetics are beginning to provide a cellular blueprint of the underlying circuitry. In these studies, manipulations of vmPFC synaptic inputs to the DRN have revealed bidirectional influences on socioaffective behaviors via direct monosynaptic excitation and indirect disynaptic inhibition of 5-HT neurons. Additionally, adverse social experiences that result in permanent avoidance biases, such as social defeat, drive long-lasting plasticity in this microcircuit, potentiating the indirect inhibition of 5-HT output. Conversely, neuromodulation of the vmPFC via deep brain stimulation (DBS) attenuates avoidance biases by restoring the direct excitatory drive of 5-HT neurons and strengthening a key subset of forebrain 5-HT projections. Better understanding the cellular organization of the vmPFC-DRN pathway and identifying molecular determinants of its neuroplasticity can open fundamentally novel avenues for the treatment of affective disorders.