Type I and type II schizophrenia: relations between tonic electrodermal activity and clinical ratings before and after haloperidol treatment.

To test the hypothesis that schizophrenic patients with positive vs. negative symptoms show different tonic electrodermal patterns, 26 patients with Type I schizophrenia and 19 patients with Type II schizophrenia were evaluated before and after 2 weeks of haloperidol treatment (standard daily dose = 4.5 mg). Clinical assessments were made with the Brief Psychiatric Rating Scale, the Scale for the Assessment of Positive Symptoms, and the Scale for the Assessment of Negative Symptoms. Skin conductance level (SCL) and spontaneous fluctuations (SF) frequency were recorded for each patient. Before treatment, Type I patients showed higher SCL and SF compared with Type II patients; after treatment, a significative decrease of clinical and psychophysiological variables was found only in Type I patients.