ABSTRACT
OBJECTIVE: The study investigated the effects of nasally administered oxytocin on neurophysiological orienting to empathy-evoking pictures in normally intelligent male adults with and without an autism spectrum disorder (ASD). It further investigated whether these effects might be moderated by the individual's approach and avoidance tendencies. METHODS: All subjects participated in a randomised double-blind placebo controlled crossover trial where either oxytocin (OXT) or placebo was administered preceding the viewing of affective pictures.The pictures, selected from the International Affective Picture System (IAPS), represented a systematic variation of pleasant, unpleasant and neutral scenes with and without humans. Both cardiac (ECR) and cortical (LPP) evoked orienting responses were measured and both were enhanced for the pictures with humans, in particular for the unpleasant ones. RESULTS: No significant group differences were found, nor were there any treatment effects. Moderator analysis, however, demonstrated that OXT did enhance orienting to affective pictures with humansin male adults with ASD who are easily distressed when seeing others in stressful situations and in healthy males who are highly sensitive to anticipated punishment and criticism or have a low drive for goal achievement. CONCLUSION: Individual differences in stress-related avoidance tendencies should be taken into account when considering OXT as a treatment of social deficiencies in autism.
