Evaluating the role of Approach-Avoidance Training on action-tendencies in individuals with skin-picking disorder: A preliminary randomized experiment

Background and aims: Pathological skin-picking (PSP) or excoriation disorder is a destructive behavior that affects 1-2% of the general population. The purpose of this pilot study was to evaluate the effect of a computerized behavior modification task on action-tendencies (i.e., approach or avoidance) in adults with PSP. We aimed to modify these action-tendencies by having participants with PSP complete the Approach-Avoidance Training (AAT) task, using a joystick to simulate an approach (=pull) or avoidance (5push) response. Method: Forty-five participants diagnosed with PSP were randomized to one of three training conditions: (1) Avoidance Training (AvT; n = 15), (2) Approach Training (ApT; n = 15), or (3) Placebo Training (PT; n = 15). We hypothesized that after training, those in the AvT would have the greatest reduction in behavioral approach (i.e., their overall reaction time [RT] to approach pictures of irregular skin stimuli). Results: Results of the pre-training assessment task revealed a positive correlation between behavioral approach to irregular skin stimuli and skin-picking severity as assessed by the Skin Picking Scale-Revised (SPS-R). After training, a lower behavioral approach and urges to pick were found in the AvT and PT groups, while those in the ApT reported higher behavioral approach and urges to pick. At two-week follow-up, no significant changes on the SPS-R were reported between groups. Discussion: Our preliminary data suggest that the AAT is a promising avenue of research to develop as a cognitive intervention to address an excessive behavioral approach tendency that characterizes skin-picking problems.