Empathy in electrodermal responsive and nonresponsive patients with schizophrenia.

Skin conductance response (SCR) to emotion-evoking stimuli has in previous studies suggested the existence of two subgroups of schizophrenia patients. One is characterized by absent SCR and the other by heightened or non-habituating SCR. These subgroups have also been shown to differ in symptoms, prognosis and social integration. The present project compared social cognition in the two subgroups. SCR from 28 patients with schizophrenia and 24 matched healthy controls was measured while they watched emotion-evoking and neutral video tapes. Assessments of symptoms, neurocognition, social cognition, and social function were also performed. Event related potentials (ERP) were recorded in response to pictures of people experiencing pain or not. Subjects were divided into "SCR non-responder" and "SCR responder" groups based on SCR frequency. Schizophrenia SCR responders had significantly higher self-reported personal distress in response to others in distress and lower P300 ERP responses to others in pain than schizophrenia SCR non-responders and healthy controls. SCR responsiveness is a potential marker of subgroups of patients with schizophrenia that differ in pathophysiology, function and prognosis.