Cocaine addicts enjoy less social interactions

Researchers have found that in addition to displaying worse memory performance, concentration difficulties, and attentional deficits, chronic cocaine users' social skills are affected.

Investigations have also revealed that cocaine users have difficulties to take the mental perspective of others, show less emotional empathy, find it more difficult to recognize emotions from voices, behave in a less prosocial manner in social interactions, and they reported fewer social contacts.

Moreover, worse emotional empathy was correlated with a smaller social network. The scientists now assume that social cognitive deficits contribute to the development and perpetuation of cocaine addiction.

The psychologists Katrin Preller and Boris Quednow, Head of the Division of Experimental and Clinical Pharmacopsychology at the Psychiatric Hospital of the University of Zurich, demonstrated that cocaine users perceived joined attention - the shared attentional focus of two persons on an object after gaze contact - as less rewarding compared to drug-naive healthy controls.

In a subsequent functional imaging experiment they showed that cocaine users showed a blunted activation of a crucial part of the reward system - the so called medial orbitofrontal cortex - during this basal kind of social interaction.

Interestingly, a weaker activation of the medial orbitofrontal cortex during social gaze contact was also associated with fewer social contacts in the past weeks.

The study has been published in the Proceedings of the National Academy of Sciences.