The effect of working memory load on selective attention towards threatening faces in socially anxious individuals: Behavioural and electrophysiological evidence
摘要
Cognitive models of anxiety propose that attention bias towards threat causes and maintains anxiety symptoms. However, the effect of working memory (WM) load on selective attention of threatening faces in individuals with socially anxious symptoms and the electrophysiological correlates are unclear. Event-related potentials (ERPs) were recorded from 30 socially anxious participants and 32 controls during an adapted emotional flanker task. Overall, socially anxious individuals showed worse accuracy and slower reaction times (RTs) in facial emotion recognition than controls. Furthermore, under high WM load, the N2 amplitudes for targets flanked by angry distractors was significantly larger than that for targets flanked by happy distractors and the late positive potential (LPP) amplitudes for angry targets was significantly larger than that for happy targets in socially anxious participants. No such effects were found for N2 and LPP amplitudes under low WM load. The results suggest the impairment of top-down cognitive control in socially anxious individuals. The increased N2 amplitudes for targets flanked by angry distractors and LPP amplitudes for angry targets under high WM load in socially anxious individuals may be related to enhanced conflict monitoring and perceptual engagement for threatening faces under conditions where cognitive resources are taxed.