Neuroleptic responsivity of negative and positive symptoms in schizophrenia.

The authors prospectively examined the effects of double-blind, placebo-controlled neuroleptic withdrawal and administration on ratings of negative and positive symptoms in 19 young patients with chronic schizophrenia. Negative symptoms were significantly reduced by neuroleptic treatment, and negative and positive symptoms demonstrated similar patterns of reduction and exacerbation during neuroleptic treatment and withdrawal, respectively. The changes in negative and positive symptoms induced by neuroleptic treatment and withdrawal were not significantly correlated, however. The negative and positive symptom profiles of individual patients were significantly altered by neuroleptic treatment, indicating limitations to the cross-sectional classification of patients on the basis of predominance of one or the other symptom group. The authors discuss implications for the neurobiological underpinnings of negative and positive symptoms.