Distinct electrocortical and behavioral evidence for increased attention to threat in generalized anxiety disorder.

BACKGROUND Neural activity is increasingly used in addition to behavioral measures to study anxiety and attentional biases toward threatening stimuli. Event-related potentials (ERPs) might be particularly useful because of their excellent temporal resolution. In particular, the late positive potential (LPP) reflects increased attention to emotional stimuli-and was recently found to be larger with increasing state anxiety. This study sought to examine the LPP among individuals with generalized anxiety disorder (GAD). METHODS Fifteen individuals with GAD and 15 healthy controls (HCs) viewed briefly presented pairs of aversive and neutral pictures that were presented to the left and right of, as well as above and below, fixation on each trial; ERP and behavioral measures were recorded as participants indicated whether the horizontal or vertical image pairs were the same or different. RESULTS Aversive pictures presented in unattended locations were associated with more errors overall, and this effect was larger in GAD than HC participants. Moreover, aversive targets elicited larger LPPs across all participants; this difference was larger in GAD than HC participants when distracters were neutral. CONCLUSIONS Threatening stimuli presented in both target and distracting spatial locations have a greater impact on GAD than HC participants. Behavioral and ERP measures provide complimentary indices of attention toward threat in GAD. In terms of attentional control theory, behavioral interference indexes impaired processing effectiveness, whereas the LPP might index reduced processing efficiency in GAD. Both measures may provide unique windows onto how increased stimulus-driven attention to threat impacts and characterizes GAD.