The behavioural and neurophysiological effects of the ‘cuddle chemical’ oxytocin may vary depending on an individual’s empathy and systematizing quotients and on the emotional context of the situation. The study, published in the journal Scientific Reports, suggests that oxytocin may not modulate prosocial behaviour in all individuals and in all contexts, but the findings need to be verified with a larger study with participants representing both genders and a greater range of ages.

Oxytocin is a hormone synthesized primarily in the central nervous system. It is thought to have an important role in the development of prosocial behaviour in humans and previous research has suggested that oxytocin administration may improve some symptoms of autism spectrum disorder (ASD), which is characterized by problems with social interactions and communication, and repetitive behaviour.

Mitsuru Kikuchi and colleagues used magnetoencephalography, a brain imaging technique, to study how an individual’s empathy quotient (EQ), autism spectrum quotient (AQ) and systematizing quotient (SQ) modulate the effects of oxytocin in the amygdala during the perception of happy, angry, neutral and ambiguous facial expressions. 20 healthy male participants were randomly assigned either to an oxytocin treatment group or to a placebo group and their EQ, AQ and SQ were measured. The authors found that oxytocin tended to enhance prosocial behavioural and neurophysiological responses in individuals with higher SQ scores and/or lower EQ scores (common traits of individuals with ASD) but only during the perception of angry faces and not other facial expressions.