The impact of sociality and affective valence on brain activation: A meta-analysis.

Thirty years of neuroimaging reveal the set of brain regions consistently associated with pleasant and unpleasant affect in humans-or the neural reference space for valence. Yet some of humans' most potent affective states occur in the context of other humans. Prior work has yet to differentiate how the neural reference space for valence varies as a product of the sociality of affective stimuli. To address this question, we meta-analyzed across 614 social and non-social affective neuroimaging contrasts, summarizing the brain regions that are consistently activated for social and non-social affective information. We demonstrate that across the literature, social and non-social affective stimuli yield overlapping activations within regions associated with visceromotor control, including the amygdala, hypothalamus, anterior cingulate cortex and insula. However, we find that social processing differs from non-social affective processing in that it involves additional cortical activations in the medial prefrontal and posterior cingulum that have been associated with mentalizing and prediction. A Bayesian classifier was able to differentiate unpleasant from pleasant affect, but not social from non-social affective states. Moreover, it was not able to classify unpleasantness from pleasantness at the highest levels of sociality. These findings suggest that highly social scenarios may be equally salient to humans, regardless of their valence.

Culture and gender modulate dlPFC integration in the emotional brain: evidence from dynamic causal modeling.

Past research has recognized culture and gender variation in the experience of emotion, yet this has not been examined on a level of effective connectivity. To determine culture and gender differences in effective connectivity during emotional experiences, we applied dynamic causal modeling (DCM) to electroencephalography (EEG) measures of brain activity obtained from Chinese and American participants while they watched emotion-evoking images. Relative to US participants, Chinese participants favored a model bearing a more integrated dorsolateral prefrontal cortex (dlPFC) during fear v. neutral experiences. Meanwhile, relative to males, females favored a model bearing a less integrated dlPFC during fear v. neutral experiences. A culture-gender interaction for winning models was also observed; only US participants showed an effect of gender, with US females favoring a model bearing a less integrated dlPFC compared to the other groups. These findings suggest that emotion and its neural correlates depend in part on the cultural background and gender of an individual. To our knowledge, this is also the first study to apply both DCM and EEG measures in examining culture-gender interaction and emotion.

Language access differentially alters functional connectivity during emotion perception across cultures.

Introduction: It is often assumed that the ability to recognize the emotions of others is reflexive and automatic, driven only by observable facial muscle configurations. However, research suggests that accumulated emotion concept knowledge shapes the way people perceive the emotional meaning of others' facial muscle movements. Cultural upbringing can shape an individual's concept knowledge, such as expectations about which facial muscle configurations convey anger, disgust, or sadness. Additionally, growing evidence suggests that access to emotion category words, such as "anger," facilitates access to such emotion concept knowledge and in turn facilitates emotion perception. Methods: To investigate the impact of cultural influence and emotion concept accessibility on emotion perception, participants from two cultural groups (Chinese and White Americans) completed a functional magnetic resonance imaging scanning session to assess functional connectivity between brain regions during emotion perception. Across four blocks, participants were primed with either English emotion category words ("anger," "disgust") or control text (XXXXXX) before viewing images of White American actors posing facial muscle configurations that are stereotypical of anger and disgust in the United States. Results: We found that when primed with "disgust" versus control text prior to seeing disgusted facial expressions, Chinese participants showed a significant decrease in functional connectivity between a region associated with semantic retrieval (the inferior frontal gyrus) and regions associated with semantic processing, visual perception, and social cognition. Priming the word "anger" did not impact functional connectivity for Chinese participants relative to control text, and priming neither "disgust" nor "anger" impacted functional connectivity for White American participants. Discussion: These findings provide preliminary evidence that emotion concept accessibility differentially impacts perception based on participants' cultural background.

Emotion depends on context, culture and their interaction: evidence from effective connectivity.

Situated models of emotion hypothesize that emotions are optimized for the context at hand, but most neuroimaging approaches ignore context. For the first time, we applied Granger causality (GC) analysis to determine how an emotion is affected by a person's cultural background and situation. Electroencephalographic recordings were obtained from mainland Chinese (CHN) and US participants as they viewed and rated fearful and neutral images displaying either social or non-social contexts. Independent component analysis and GC analysis were applied to determine the epoch of peak effect for each condition and to identify sources and sinks among brain regions of interest. We found that source-sink couplings differed across culture, situation and culture × situation. Mainland CHN participants alone showed preference for an early-onset source-sink pairing with the supramarginal gyrus as a causal source, suggesting that, relative to US participants, CHN participants more strongly prioritized a scene's social aspects in their response to fearful scenes. Our findings suggest that the neural representation of fear indeed varies according to both culture and situation and their interaction in ways that are consistent with norms instilled by cultural background.

Location-dependent threat and associated neural abnormalities in clinical anxiety.

Anxiety disorders are characterized by maladaptive defensive responses to distal or uncertain threats. Elucidating neural mechanisms of anxiety is essential to understand the development and maintenance of anxiety disorders. In fMRI, patients with pathological anxiety (ANX, n = 23) and healthy controls (HC, n = 28) completed a contextual threat learning paradigm in which they picked flowers in a virtual environment comprising a danger zone in which flowers were paired with shock and a safe zone (no shock). ANX compared with HC showed 1) decreased ventromedial prefrontal cortex and anterior hippocampus activation during the task, particularly in the safe zone, 2) increased insula and dorsomedial prefrontal cortex activation during the task, particularly in the danger zone, and 3) increased amygdala and midbrain/periaqueductal gray activation in the danger zone prior to potential shock delivery. Findings suggest that ANX engage brain areas differently to modulate context-appropriate emotional responses when learning to discriminate cues within an environment.

Statistical power comparisons at 3T and 7T with a GO / NOGO task.

The field of cognitive neuroscience is weighing evidence about whether to move from standard field strength to ultra-high field (UHF). The present study contributes to the evidence by comparing a cognitive neuroscience paradigm at 3 Tesla (3T) and 7 Tesla (7T). The goal was to test and demonstrate the practical effects of field strength on a standard GO/NOGO task using accessible preprocessing and analysis tools. Two independent matched healthy samples (N = 31 each) were analyzed at 3T and 7T. Results show gains at 7T in statistical strength, the detection of smaller effects and group-level power. With an increased availability of UHF scanners, these gains may be exploited by cognitive neuroscientists and other neuroimaging researchers to develop more efficient or comprehensive experimental designs and, given the same sample size, achieve greater statistical power at 7T.

The role of ventral striatum in reward-based attentional bias.

INTRODUCTION: Models of attention suggest that endogenous and exogenous factors can bias attention. However, recent data suggest that reward can also enhance attention towards relevant stimulus features as a function of involuntary biases. In this study, we utilized the additional singleton task to determine the neural circuitry that biases perceptual processing as a function of reward history. METHODS: Participants searched for a unique shape amongst an array of differently shaped objects. All shapes, including the target shape, had the same color except one distractor shape. Participants randomly received a low or high reward after correct trials. From one trial to the next, target colors could stay the same or swap with the distractor color. Interestingly, and despite the irrelevancy of reward magnitude for task accuracy, the difference in reaction time between swap and non-swap trials usually is more pronounced following a high compared to a low reward. RESULTS: In the current study, we showed that reward modulated attention is larger for individuals with enhanced reward magnitude sensitivity in the ventral striatum. In addition, connectivity data shows that ventral striatum was more positively connected with visual cortex during high reward non-swap trials compared to high reward swap trials for participants showing stronger reward modulated attention. CONCLUSIONS: This suggests that involuntary reward modulated attention might be implemented by direct influences of the ventral striatum on visual cortex.

Looming Threats and Animacy: Reduced Responsiveness in Youth with Disrupted Behavior Disorders.

Theoretical models have implicated amygdala dysfunction in the development of Disruptive Behavior Disorders (DBDs; Conduct Disorder/Oppositional Defiant Disorder). Amygdala dysfunction impacts valence evaluation/response selection and emotion attention in youth with DBDs, particularly in those with elevated callous-unemotional (CU) traits. However, amygdala responsiveness during social cognition and the responsiveness of the acute threat circuitry (amygdala/periaqueductal gray) in youth with DBDs have been less well-examined, particularly with reference to CU traits. 31 youth with DBDs and 27 typically developing youth (IQ, age and gender-matched) completed a threat paradigm during fMRI where animate and inanimate, threatening and neutral stimuli appeared to loom towards or recede from participants. Reduced responsiveness to threat variables, including visual threats and encroaching stimuli, was observed within acute threat circuitry and temporal, lateral frontal and parietal cortices in youth with DBDs. This reduced responsiveness, at least with respect to the looming variable, was modulated by CU traits. Reduced responsiveness to animacy information was also observed within temporal, lateral frontal and parietal cortices, but not within amygdala. Reduced responsiveness to animacy information as a function of CU traits was observed in PCC, though not within the amygdala. Reduced threat responsiveness may contribute to risk taking and impulsivity in youth with DBDs, particularly those with high levels of CU traits. Future work will need to examine the degree to which this reduced response to animacy is independent of amygdala dysfunction in youth with DBDs and what role PCC might play in the dysfunctional social cognition observed in youth with high levels of CU traits.

Prediction Error Representation in Individuals With Generalized Anxiety Disorder During Passive Avoidance.

OBJECTIVE: Deficits in reinforcement-based decision making have been reported in generalized anxiety disorder. However, the pathophysiology of these deficits is largely unknown; published studies have mainly examined adolescents, and the integrity of core functional processes underpinning decision making remains undetermined. In particular, it is unclear whether the representation of reinforcement prediction error (PE) (the difference between received and expected reinforcement) is disrupted in generalized anxiety disorder. This study addresses these issues in adults with the disorder. METHOD: Forty-six unmedicated individuals with generalized anxiety disorder and 32 healthy comparison subjects group-matched on IQ, gender, and age performed a passive avoidance task while undergoing functional MRI. Data analyses were performed using a computational modeling approach. RESULTS: Behaviorally, individuals with generalized anxiety disorder showed impaired reinforcement-based decision making. Imaging results revealed that during feedback, individuals with generalized anxiety disorder relative to healthy subjects showed a reduced correlation between PE and activity within the ventromedial prefrontal cortex, ventral striatum, and other structures implicated in decision making. In addition, individuals with generalized anxiety disorder relative to healthy participants showed a reduced correlation between punishment PEs, but not reward PEs, and activity within the left and right lentiform nucleus/putamen. CONCLUSIONS: This is the first study to identify computational impairments during decision making in generalized anxiety disorder. PE signaling is significantly disrupted in individuals with the disorder and may lead to their decision-making deficits and excessive worry about everyday problems by disrupting the online updating ("reality check") of the current relationship between the expected values of current response options and the actual received rewards and punishments.