A nasal oxytocin spray might curtail dominant behavior in psychopaths

Scientists have uncovered preliminary evidence that oxytocin, a neurohormone that reduces stress and fosters social bonding, could help to reduce dominant behavior in psychopathic offenders. Their findings have been published in the journal Psychoneuroendocrinology.

“As a psychiatrist, I previously worked with victims of organized violence and became aware of the phenomenon of secondary psychopathization within trauma patients suffering from chronic trauma psychopathology,” said lead researcher Ronald J.P. Rijnders, a psychiatrist affiliated with the Netherlands Institute of Forensic Psychiatry and Psychology.

“After moving to forensic psychiatry, I met many primary psychopaths in the Dutch forensic observation clinic Pieter Baan Centrum. Psychopathy is an interesting phenomenon with prevalence rates of 0.5 to 1% worldwide. If these prevalence rates were to become higher within a system, the system would tend to collapse into chaos and, ultimately, war would result.”

“Such conditions pave the way to organized violence perpetrated by, especially, psychopaths, after which the likelihood of psychotraumatization of victims increases. It is this experience that leads me to believe that as a psychiatrist, one must be aware of both the effects of psychotrauma and antisocial, psychopathic behavior,” Rijnders said.

The study compared the performance of 21 psychopathic patients to 24 non-psychopathic individuals on a gaze aversion task, which assessed how long it took for participants to look away from faces with neutral, happy, or angry expressions. Previous research has indicated that more dominant individuals tend to be slower to avert their gaze from angry faces.

Psychopathic patients completed the gaze aversion task twice, once after using a nasal spray containing oxytocin and once after using a placebo nasal spray. The controls only completed the gaze aversion task once and did not use a nasal spray.

The patients were recruited from maximum security psychiatric hospitals in the Netherlands, and had completed a forensic interview known as the Hare Psychopathy Checklist–Revised. The non-psychopathic controls, on the other hand, were recruited from the hospitals’ staff and completed a non-forensic assessment of psychopathy.

“We identified psychopathic patients and compared them to normal controls (i.e., professionals without psychopathy),” Rijnders explained.

Rijnders and his team were surprised to find that psychopathic patients (after sniffing placebo) did not exhibit more dominant behavior during the gaze aversion task on average than the control group. However, severe psychopathy was positively associated with more dominant behavior. The researchers also found evidence that a single nasal spray administration of oxytocin reduced dominant behavior among patients who scored high on the Hare Psychopathy Checklist–Revised.

“Just as psychopathy is a burden on society, so can socially dominant behavior be. It takes no imagination to understand that socially dominant psychopaths are an additional burden,” Rijnders told PsyPost. “The group of psychopathic patients as a whole did not appear to score more dominantly on a computer task measuring dominance than the group of normal controls. This was not expected. However, within the group of psychopaths we did find that the higher the psychopathy score, the higher the dominance rate. Indeed, we did expect this result.”

“Nasal administration of oxytocin removed the relationship between psychopathy score and dominant behavior. This was a striking finding. Of course, further research into this relationship is needed, but we would welcome studies in which oxytocin plays a role in the treatment of psychopaths, especially the socially dominant ones among them,” Rijnders said.

The researchers noted that the mechanism behind oxytocin’s effect on psychopathic individuals is unclear and needs further investigation.

“The study group involved a group of psychopathic patients who have been in treatment in a forensic psychiatric clinic for a long time. That group cannot be compared to untreated psychopaths. Furthermore, the study group was small, so the power of the study is low,” Rijnders explained.

The study, “Sniffing submissiveness? Oxytocin administration in severe psychopathy“, was authored by Ronald J.P. Rijnders, Anouk H. Dykstra, David Terburg, Maaike M. Kempes, and Jack van Honk.