Nonverbal social behaviors of patients with bipolar mania during interactions with virtual humans.

It has been proposed that positive emotional biases could make bipolar manic (BM) patients maintain abnormally approaching behaviors during social interactions. To test this hypothesis, we measured interpersonal distance (IPD) and gaze angle of BM patients and normal controls (NCs) during social interaction in immersive virtual environment. Overall, IPDs of BM patients (n = 20) were greater than those of normal controls (n = 20). The IPD difference was even greater between NCs and BM patients with psychotic features (n = 11) than those without psychotic features (n = 9). Regardless of the presence of psychotic features, BM patients averted their gazes more than NCs, and even more while speaking than while listening. Our results might suggest negativistic social cognition of bipolar patients, as was previously found even during a manic phase, or the role of paranoid symptoms in avoidant social behaviors, in agreement with prior studies with schizophrenic patients. Use of proper space and gaze might have psychotherapeutic implication in developing secure, two-person relationship with bipolar patients regardless of the presence of disrupting manic symptoms.