The psychophysiology of social anxiety: emotional modulation of the startle reflex during socially-relevant and -irrelevant pictures.

The present study examined affective processes of social anxiety (SA) through emotional modulation of the startle reflex. Eighty-four high and low trait socially anxious undergraduates viewed socially-relevant and socially-irrelevant pleasant, neutral, and unpleasant pictures, and acoustic startle probes were presented during pictures and the inter-trial interval. Startle was potentiated during unpleasant compared to pleasant stimuli, but this valence modulation did not reliably vary between groups or socially-relevant and -irrelevant stimuli. However, when participants were categorized based on public-speaking fears rather than general SA symptoms, the high fear group demonstrated reliable valence modulation, whereas the low fear group did not. These findings are interpreted within the context of the broader literature suggesting that the specificity of fear in SA may influence psychophysiological reactivity.