Attentional bias for emotional faces in generalized anxiety disorder

Objectives. Recent cognitive theories propose that attentional biases cause or maintain anxiety disorders. This study had several aims: (i) to investi gate such biases in generalized anxiety disorder (GAD) using naturalistic, ecologically valid stimuli, namely, emotional facial expressions; (ii) to t est the emotionality hypothesis by examining biases for happy as well as th reat faces; and (iii) to assess the time course of the attentional bias. Design. The dependent variable was an index of attentional bias derived fro m manual RTs to probe stimuli. There were four independent variables: one b etween subjects variable of group (2: GAD, control), and three within-subje cts variables: Type of emotional face (2: threat, happy), Stimulus duration (2: 500 ms, 1250 ms) and Half of task (2: first, second). Method. Attentional bias was assessed with a dot probe task. The stimuli co mprised photographs of threatening, happy and neutral faces, presented usin g two exposure durations: 500 ms and 1250 ms. Results. Anxious patients showed greater vigilance for threatening faces re lative to neutral faces, compared with normal controls. This effect did not significantly vary as a function of stimulus duration. Anxious patients al so showed enhanced vigilance for happy faces, but this was only significant in the second half of the task. Conclusions. The study confirmed not only that GAD patients show a bias in selective attention to threat, relative to controls, but also that this bia s operates for naturalistic, non-verbal stimuli. As the attentional biases for threat and happy faces appeared to develop over a different time frame, different underlying mechanisms may be responsible.