Quality and temporal properties of premonitory urges in patients with skin picking disorder

Skin picking is a newly recognized obsessive-compulsive spectrum disorder in DSM-5. Similar to some repetitive behaviors in Gilles de la Tourette syndrome (GTS) and obsessive-compulsive disorder (OCD), premonitory urges are assumed to play a critical role in maintaining skin picking behavior, by creating a vicious cycle. The present study is the first to investigate the quality of premonitory urges, as well as the temporal relationship between urges and skin picking behavior in individuals with skin picking disorder. Quality and intensity of premonitory urges was assessed in 15 individuals with skin picking. Urge quality was assessed with the translated University of São Paulo Sensory Phenomena Scale (USP-SPS). Urge intensity was assessed continuously over 20 min using a computer-based tool. Participants were instructed either a) to pick freely or b) to suppress their skin picking behavior. Skin picking events during the free and suppression condition were recorded on video and coded manually. Regarding the types of urges, individuals with skin picking reported mainly physical urge sensations (80%), visual "just-right" feelings (80%), and urge-only sensations (80%) similar to urges reported by GTS and OCD patients. Moreover, the data showed a strong temporal relationship between the intensity of premonitory urges and the emergence of skin picking behavior (R² = .23) that was weakened when skin picking was suppressed (R² = .06). The results suggest that skin picking behavior is maintained by premonitory urges and that this vicious cycle of negative reinforcement can be, at least partially, broken by suppressing skin picking behavior.