"Do you copy? ": Automatic imitation among individuals with high versus low obsessive-compulsive symptoms

Abstract

Humans often 'automatically' imitate the movements of their peers and these actions may support adaptive social behaviour. Individuals with high obsessive-compulsive (OC) symptoms exhibit atypical social behaviour relating to imitation. Differences in automatic imitation may partially explain atypical social behaviour in OC populations, but the integrity of these actions has yet to be tested. As such, the current study examined potential differences in automatic imitation among individuals varying in OC symptoms. Participants (n=50, 30 female) completed a questionnaire measuring OC (Obsessive Compulsive Inventory-Revised: OCI-R) and comorbid (Beck Anxiety Inventory: BAI) symptoms. Then, participants completed an experiment requiring index or little finger keypress responses following the presentation of congruent (overlapping locations) or incongruent (opposite locations) finger and dot movements; finger movements were downwards motions of a model's index or little finger, whereas dot movements were downwards motions of white dots superimposed onto a model's index or little finger. Using inverse efficiency scores, automatic imitation was measured as larger interference effects (Incongruent trials – Congruent trials) with finger versus dot movements as the distractor. Participants were subdivided (OCI-R scores below/above 21) into age/gender matched Low-OC (LOC; n=18) and High-OC (HOC; n=18) groups. Including BAI scores as a covariate, interference effects were larger in the HOC (M=189.66ms) versus LOC (M=117.24ms; p<0.01) group. However, interference effects in the HOC group were not different with finger (M=200.68ms) versus dot (M=178.64ms; p>.05) movements as the distractor. Differences in general interference control, but not in 'automatic' imitation per se, may be present among individuals with high OC symptoms.