Trait-level somatic anxiety modulates functional magnetic resonance imaging (fMRI) neural synchrony to naturalistic stimuli.

Somatic anxiety refers to the tendency to appraise situations as threatening, leading to heightened physiological arousal. Symptoms associated with higher levels of somatic anxiety that reflect autonomic arousal and perceptions of threat include elevated heartbeat perception, difficulty breathing, and palpitation. Somatic anxiety is generally associated with increased stimulus-driven attention; however, it is currently unknown how somatic anxiety modulates neural synchrony, measured by intersubject correlations (ISC), in response to complex audiovisual stimuli. The present study seeks to identify how differing levels of somatic anxiety are associated with neural synchrony during psychological processing of audiovisual stimuli, as measured by ISC and intersubject representational similarity analyses. We hypothesize that individuals with higher levels of somatic anxiety will show heightened ISC in response to an audiovisual stimulus in regions associated with stimulus-driven attention, including the superior parietal lobule, supplementary motor area, and precentral gyrus. Results from this study identified that higher levels of somatic anxiety are associated with widespread heightened ISC across the brain, including in regions associated with perceptual processing and stimulus-driven attention. Taken together, this research suggests that higher levels of somatic anxiety are associated with similar processing in brain regions involved in stimulus-driven attention and top-down processing, whereas lower levels of somatic anxiety are associated with similar processing in brain regions associated with higher level visual processing. These results collectively emphasize that somatic anxiety levels should be measured and controlled for during naturalistic functional magnetic resonance imaging paradigms, as this trait may have an influence on synchronous neurological activity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).