Skin conductance responsivity during acute episodes of schizophrenia as a predictor of symptomatic improvement

Skin conductance responses to a series of tones were measured in 41 patients during an acute episode of schizophrenia before they received treatment and after 4 weeks of treatment with either alpha-flupenthixol, beta-flupenthixol or placebo. Patients who did not habituate to the tones prior to treatment tended to show no symptomatic improvement during the course of treatment. Patients who habituated and also showed an acute onset of their current symptoms ('Feighner negative' patients) showed a marked improvement even without active medication. Skin conductance responsivity did not change with improvement in symptoms alone, but decreased in patients on active medication (alpha-flupenthixol). Non-habituation of skin conductance and insidious onset (i.e. fulfilment of the Feighner criteria) were found to be independent predictors of poor outcome. Taken together, these criteria may define a group of patients with particularly poor prognosis.