Impairments in goal-directed actions predict treatment response to cognitive-behavioral therapy in social anxiety disorder

Abstract

Social anxiety disorder is characterized by excessive fear and habitual avoidance of social situations. Decision-making models suggest that patients with anxiety disorders may fail to exhibit goal-directed control over actions. We therefore investigated whether such biases may also be associated with social anxiety and to examine the relationship between such behavior with outcomes from cognitive-behavioral therapy. Patients diagnosed with social anxiety and controls completed an instrumental learning task in which two actions were performed to earn food outcomes. After outcome devaluation, where one outcome was consumed to satiety, participants were re-tested in extinction. Results indicated that, as expected, controls were goal-directed, selectively reducing responding on the action that previously delivered the devalued outcome. Patients with social anxiety, however, exhibited no difference in responding on either action. This loss of a devaluation effect was associated with greater symptom severity and poorer response to therapy. These findings indicate that variations in goal-directed control in social anxiety may represent both a behavioral endophenotype and may be used to predict individuals who will respond to learning-based therapies.

Figure 1. Instrumental task during training.

One of two fractal cues was associated with a keyboard button (depicted in the yellow squares) and a food outcome (savory biscuits or chocolate). Food outcomes were available on a variable interval 10 (VI-10) schedule. Trials were presented randomly, lasting between 20 and 40 seconds each within a six minute block. Rest trials in which no reward is available were randomly presented in between trials, lasting for 10 seconds. Cumulative earnings were displayed at the end of each block.

Figure 2. Difference in mean rates of responding for actions predicting valued relative to devalued outcomes over the last block of training and extinction trials in controls compared to social anxiety disorder patients.

Error bars depict standard error of the mean difference between controls and patients. *p<.05.