Task-dependent neural bases of perceiving emotionally expressive targets

Impaired empathic accuracy following damage to the left hemisphere

Failing to understand others accurately can be extremely costly. Unfortunately, events such as strokes can lead to a decline in emotional understanding. Such impairments have been documented in stroke patients and are widely hypothesized to be related to right-hemisphere lesions, as well as to the amygdala, and are thought to be driven in part by attentional biases, for example, less fixation on the eyes. Notably, most of the previous research relied on measurements of emotional understanding from simplified cues, such as facial expressions or prosody. We hypothesize that chronic damage to the left hemisphere could hinder empathic accuracy and emotion recognition in naturalistic social settings that require complex language comprehension, even after a patient regains core language capacities. To assess this notion, we use an empathic accuracy task and eye-tracking measurements with chronic stroke patients with either right (N = 13) or left (N = 11) hemispheric damage-together with aged-matched controls (N = 15)-to explore the patients' understanding of others' affect inferred from stimuli that separates audio and visual cues. While we find that patients with right-hemisphere lesions showed visual attention bias compared to the other two groups, we uncover a disadvantage for patients with left-hemisphere lesions in empathic accuracy, especially when only auditory cues are present. These results suggest that patients with left-hemisphere damage have long-lasting difficulties comprehending real-world complex emotional situations.

Longitudinal Change in Neural Response to Vocal Emotion in Adolescence

Adolescence is associated with maturation of function within neural networks supporting the processing of social information. Previous longitudinal studies have established developmental influences on youth’s neural response to facial displays of emotion. Given the increasing recognition of the importance of non-facial cues to social communication, we build on existing work by examining longitudinal change in neural response to vocal expressions of emotion in 8- to 19-year-old youth. Participants completed a vocal emotion recognition task at two timepoints (1 year apart) while undergoing functional magnetic resonance imaging. The right inferior frontal gyrus, right dorsal striatum and right precentral gyrus showed decreases in activation to emotional voices across timepoints, which may reflect focalization of response in these areas. Activation in the dorsomedial prefrontal cortex was positively associated with age but was stable across timepoints. In addition, the slope of change across visits varied as a function of participants’ age in the right temporo-parietal junction (TPJ): this pattern of activation across timepoints and age may reflect ongoing specialization of function across childhood and adolescence. Decreased activation in the striatum and TPJ across timepoints was associated with better emotion recognition accuracy. Findings suggest that specialization of function in social cognitive networks may support the growth of vocal emotion recognition skills across adolescence.

Escitalopram modulates learning content-specific neuroplasticity of functional brain networks

Learning-induced neuroplastic changes, further modulated by content and setting, are mirrored in brain functional connectivity (FC). In animal models, selective serotonin reuptake inhibitors (SSRIs) have been shown to facilitate neuroplasticity. This is especially prominent during emotional relearning, such as fear extinction, which may translate to clinical improvements in patients. To investigate a comparable modulation of neuroplasticity in humans, 99 healthy subjects underwent three weeks of emotional (matching faces) or non-emotional learning (matching Chinese characters to unrelated German nouns). Shuffled pairings of the original content were subsequently relearned for the same time. During relearning, subjects received either a daily dose of the SSRI escitalopram or placebo. Resting-state functional magnetic resonance imaging was performed before and after the (re-)learning phases. FC changes in a network comprising Broca's area, the medial prefrontal cortex, the right inferior temporal and left lingual gyrus were modulated by escitalopram intake. More specifically, it increased the bidirectional connectivity between medial prefrontal cortex and lingual gyrus for non-emotional and the connectivity from medial prefrontal cortex to Broca's area for emotional relearning. The context dependence of these effects together with behavioral correlations supports the assumption that SSRIs in clinical practice improve neuroplasticity rather than psychiatric symptoms per se. Beyond expanding the complexities of learning, these findings emphasize the influence of external factors on human neuroplasticity.

Interplay Between the Salience and the Default Mode Network in a Social-Cognitive Task Toward a Close Other

Social cognition relies on two main subsystems to construct the understanding of others, which are sustained by different social brain networks. One of these social networks is the default mode network (DMN) associated with the socio-cognitive subsystem (i.e., mentalizing), and the other is the salience network (SN) associated with the socio-affective route (i.e., empathy). The DMN and the SN are well-known resting state networks that seem to constitute a baseline for the performance of social tasks. We aimed to investigate both networks' functional connectivity (FC) pattern in the transition from resting state to social task performance. A sample of 38 participants involved in a monogamous romantic relationship completed a questionnaire of dyadic empathy and underwent an fMRI protocol that included a resting state acquisition followed by a task in which subjects watched emotional videos of their romantic partner and elaborated on their partner's (Other condition) or on their own experience (Self condition). Independent component and ROI-to-ROI correlation analysis were used to assess alterations in task-independent (Rest condition) and task-dependent (Self and Other conditions) FC. We found that the spatial FC maps of the DMN and SN evidenced the traditional regions associated with these networks in the three conditions. Anterior and posterior DMN regions exhibited increased FC during the social task performance compared to resting state. The Other condition revealed a more limited SN's connectivity in comparison to the Self and Rest conditions. The results revealed an interplay between the main nodes of the DMN and the core regions of the SN, particularly evident in the Self and Other conditions.

Friend versus foe: Neural correlates of prosocial decisions for liked and disliked peers

Although the majority of our social interactions are with people we know, few studies have investigated the neural correlates of sharing valuable resources with familiar others. Using an ecologically valid research paradigm, this functional magnetic resonance imaging study examined the neural correlates of prosocial and selfish behavior in interactions with real-life friends and disliked peers in young adults. Participants (N = 27) distributed coins between themselves and another person, where they could make selfish choices that maximized their own gains or prosocial choices that maximized outcomes of the other. Participants were more prosocial toward friends and more selfish toward disliked peers. Individual prosociality levels toward friends were associated negatively with supplementary motor area and anterior insula activity. Further preliminary analyses showed that prosocial decisions involving friends were associated with heightened activity in the bilateral posterior temporoparietal junction, and selfish decisions involving disliked peers were associated with heightened superior temporal sulcus activity, which are brain regions consistently shown to be involved in mentalizing and perspective taking in prior studies. Further, activation of the putamen was observed during prosocial choices involving friends and selfish choices involving disliked peers. These findings provide insights into the modulation of neural processes that underlie prosocial behavior as a function of a positive or negative relationship with the interaction partner.

Altered spontaneous brain activity in adolescent boys with pure conduct disorder revealed by regional homogeneity analysis

Functional magnetic resonance imaging (fMRI) studies have revealed abnormal neural activity in several brain regions of adolescents with conduct disorder (CD) performing various tasks. However, little is known about the spontaneous neural activity in people with CD in a resting state. The aims of this study were to investigate CD-associated regional activity abnormalities and to explore the relationship between behavioral impulsivity and regional activity abnormalities. Resting-state fMRI (rs-fMRI) scans were administered to 28 adolescents with CD and 28 age-, gender-, and IQ-matched healthy controls (HCs). The rs-fMRI data were subjected to regional homogeneity (ReHo) analysis. ReHo can demonstrate the temporal synchrony of regional blood oxygen level-dependent signals and reflect the coordination of local neuronal activity facilitating similar goals or representations. Compared to HCs, the CD group showed increased ReHo bilaterally in the insula as well as decreased ReHo in the right inferior parietal lobule, right middle temporal gyrus and right fusiform gyrus, left anterior cerebellum anterior, and right posterior cerebellum. In the CD group, mean ReHo values in the left and the right insula correlated positively with Barratt Impulsivity Scale (BIS) total scores. The results suggest that CD is associated with abnormal intrinsic brain activity, mainly in the cerebellum and temporal-parietal-limbic cortices, regions that are related to emotional and cognitive processing. BIS scores in adolescents with CD may reflect severity of abnormal neuronal synchronization in the insula.

Cue Integration: A Common Framework for Social Cognition and Physical Perception

Scientists examining how people understand other minds have long thought that this task must be something like how people perceive the physical world. This comparison has proven to be deeply generative, as models of physical perception and social cognition have evolved in parallel. In this article, I propose extending this classic analogy in a new direction by proposing cue integration as a common feature of social cognition and physical perception. When encountering complex social cues-which happens often-perceivers use multiple processes for understanding others' minds. Like physical senses (e.g., vision or audition), social cognitive processes have often been studied as though they operate in relative isolation. In the domain of physical perception, this assumption has broken down, following evidence that perception is instead characterized by pervasive integration of multisensory information. Such integration is, in turn, elegantly described by Bayesian inferential models. By adopting a similar cue integration framework, researchers can similarly understand and formally model the ways that we perceive others' minds based on complex social information.

Inferences of Others' Competence Reduces Anticipation of Pain When under Threat

On a daily basis, we place our lives in the hands of strangers. From dentists to pilots, we make inferences about their competence to perform their jobs and consequently to keep us from harm. Here we explore whether the perceived competence of others can alter one's anticipation of pain. In two studies, participants (Receivers) believed their chances of experiencing an aversive stimulus were directly dependent on the performance of another person (Players). We predicted that perceiving the Players as highly competent would reduce Receivers' anxiety when anticipating the possibility of an electric shock. Results confirmed that high competence ratings consistently corresponded with lower reported anxiety, and complementary fMRI data showed that increased competence perception was further expressed as decreased activity in the bilateral posterior insula, a region localized to actual pain stimulation. These studies suggest that inferences of competence act as predictors of protection and reduce the expectation of negative outcomes.

Selective attention effects on early integration of social signals: same timing, modulated neural sources

Humans combine co-emitted social signals to predict other's immediate intentions and prepare an adapted response. However, little is known about whether attending to only one of co-emitted social signals impacts on its combination with other signals. Here, using electroencephalography, we address selective attention effects on early combination of social signals. We manipulated three visual cues: gaze direction, emotional expression, and pointing gesture, while participants performed either emotion or gaze direction judgments. Results showed that a temporal marker of social cues integration emerges 170ms after the stimulus onset, even if the integration of the three visual cues was not required to perform the task, as only one feature at a time was task relevant. Yet in addition to common temporal regions, the relative contribution of specific neural sources of this integration changed as a function of the attended feature: integration during emotion judgments was mainly implemented in classic limbic areas but in the dorsal pathway during gaze direction judgments. Together, these findings demonstrate that co-emitted social cues are integrated as long as they are relevant to the observer, even when they are irrelevant to the ongoing task.