Background

Exaggerated anticipatory anxiety is common in social anxiety disorder (SAD). Neuroimaging studies have revealed altered neural activity in response to social stimuli in SAD, but fewer studies have examined neural activity during anticipation of feared social stimuli in SAD. The current study examined the time course and magnitude of activity in threat processing brain regions during speech anticipation in socially anxious individuals and healthy controls (HC).

Method

Participants (SAD n=58; HC n=16) underwent functional magnetic resonance imaging (fMRI) during which they completed a 90s control anticipation task and 90s speech anticipation task. Repeated measures multi-level modeling analyses were used to examine group differences in time course activity during speech vs. control anticipation for regions of interest, including bilateral amygdala, insula, ventral striatum, and dorsal anterior cingulate cortex.

Results

The time course of amygdala activity was more prolonged and less variable throughout speech anticipation in SAD participants compared to HCs, whereas the overall magnitude of amygdala response did not differ between groups. Magnitude and time course of activity was largely similar between groups across other regions of interest.

Limitations

Analyses were restricted to regions of interest and task order was the same across participants due to the nature of deception instructions.

Conclusions

Sustained amygdala time course during anticipation may uniquely reflect heightened detection of threat or deficits in emotion regulation in socially anxious individuals. Findings highlight the importance of examining temporal dynamics of amygdala responding.

Self-referential processing is critical to understanding social anxiety disorder (SAD). This study examined neural differences in self-referential processing in healthy controls (HC) and participants with SAD at pre- and post-treatment. Participants (n = 64) underwent fMRI scanning while viewing a video of themselves ("Self") or another person ("Other"). SAD participants were randomized to cognitive behavior therapy (CBT), acceptance and commitment therapy (ACT), or waitlist, and were re-scanned at post-treatment. In SAD vs. HC, the fusiform face area (FFA) showed significantly more activation during Self vs. Other, and greater SAD severity was associated with significantly more activation during Self vs. Other in the right FFA and the left extrastriate body area (EBA). Greater reduction in SAD severity was associated with stronger connectivity between the amygdala and FFA during Self vs. Other at post-treatment, whereas the strength of connectivity during Self and Other was comparable at post-treatment for those with less SAD reduction. Thus, there were significant differences in activation and functional connectivity of brain regions implicated in self-referential processing in SAD. Change in connectivity between the amygdala and FFA were observed as a function of change in SAD severity, suggesting that improvements in SAD severity may correct this altered functional connectivity.