A dose of the hormone Oxytocin reduces the stress hormone Cortisol in arguing couples. In addition, Oxytocin strengthens positive behaviour,as researchers at the University of Zurich have discovered. The study by the psychologist Beate Ditzen has appeared in the specialist magazine “Biological Psychiatry”.

Various studies in recent years have repeatedly shown that the hormone Oxytocin in the brain of mammals – and therefore human beings too – is jointly responsible for regulating the social behaviour. Beate Ditzen from the Psychological Institute of the UZH has now, together with colleagues from the University of Zurich, examined the hormone particularly in terms of the behaviour in partnerships.

The scientists asked 47 couples aged between 20 and 50 to argue in the laboratory about a typical subject of conflict for them. Before this conflict discussion, the couples received either the hormone Oxytocin or a placebo in the form of a nasal spray. The behaviour of the couples was recorded on video and analysed with the aid of a coding system. Moreover, the stress hormone Cortisol was repeatedly measured in the saliva of both partners in order to record the psychobiological stress reaction to the conflict.

Beate Ditzen and her colleagues then assessed the positive behaviour, such as listening, confirming or laughing during the conflict in relation to the negative conflict behaviour such as interrupting, criticising or degrading the partner. “Couples that received Oxytocin behaved significantly more positively than couples with the placebo”, said Beate Ditzen in summarising the results. Oxytocin prolongs the duration of positive behaviour in relation to negative behaviour. In addition, the Cortisol values of couples who received Oxytocin were lower after the conflict than those of the placebo group.

The results suggest that Oxytocin as a neuronal mechanism might influence the behaviour and the stress reaction in couples. “Oxytocin might be a possible biological candidate to explain how close relationships – and particularly couple relationships – have a positive effect on our health” explains Beate Ditzen.