Mutability and relationship between positive and negative symptoms during neuroleptic treatment in schizophrenia.

The positive/negative symptom dichotomy is being increasingly utilized to explain the beterogeneity of schizophrenia, and poor response to neuroleptic treatment has traditiona!ly been considered to be one of the characteristic features of the negative syndrome. This issue was emphasized by Crow (1980), who principally based this conclusion on the study by Iohnstone et al. (1978), which found that cis-flupenthixol, a dopamine (DA) receptor blocker, significantly reduced positive symptoms, but was no more effective on negative symptoms than trans-flupenthixol, an isomer of cis-flupenthixol without DA antagonist properties. Crow suggested that increased dopaminergic activity was the basis of the neuroleptic-responsive positive symptoms which were predominant in the so-called type I syndrome, whereas structural brain abnormalities marked by ventricular enlargement were the basis of the neuroleptic-nonresponsive negative symptoms that characterized the type II syndrome. The association between negative symptoms, poor response to neurolepfics, and yen-