P.3.004 Association of antidepressant therapy with onset of mania

Abstract

participants’ gaze behavior was recorded by an eyetracking device that also controlled the gaze of an anthropomorphic virtual character. Joint attention and nonjoint attention trials were conducted. Pupil size, valence and arousal ratings were assessed. Data were analysed by mixed-effects analyses of variance with group as between-subjects factor, and joint (joint vs. nonjoint attention) as within-subjects factor. In Study II, 16 cocaine users and 16 controls completed a similar paradigm, while undergoing functional magnetic resonance imaging (fMRI). Additionally, individual social network size was evaluated using the Social Network Questionnaire. FMRI images were analyzed using a GLM as implemented in SPM8. Valence ratings revealed that cocaine users differentiated less between joint attention and nonjoint attention than controls [interaction group × joint for valence ratings: F(1,141) = 4.35, p< 0.04], while arousal ratings additionally reflect altered emotional engagement than controls [interaction group × joint for arousal ratings: F(1,141) = 3.94, p< 0.05]. Subjective ratings were in line with reduced pupil responses in cocaine users [interaction group × joint for pupil size: F(1,130) = 4.91, p< 0.03]. Furthermore, in response to social interaction cocaine users displayed decreased activation of the medial orbitofrontal cortex (mOFC) (peak: x = −6, y = 56, z = −5, p< 0.05, FWE) − a key region of reward processing. Moreover, blunted activation of the mOFC was significantly correlated with a decreased social network size (r = 0.35, p< 0.05). In conclusion, the results suggest that basic social interaction deficits such as altered gaze contact probably arise from blunted social reward processing. Furthermore, these alterations in social gaze processing seem to be related to impaired real-life social behavior in cocaine users. Understanding the basis of social cognition deficits in stimulant users offers the possibility to develop new targets for prevention and treatment strategies. Our results point to the importance of reinstatement of social reward in the treatment of stimulant addiction to abate harm caused by altered social processing in substance use disorders.