FOS and schizophrenia: On the other hand, the induction of c-fos expression in prefrontal cortex and limbic striatum by atypical antipsychotics (e.g., clozapine; Robertson et al., 1994) has been potentially correlated with the ability of these compounds to impact, at least in part, brain circuitry implicated in the pathophysiology of negative symptoms of schizophrenia, based on the hypothesis explaining negative symptoms with a potential hypo-frontality in schizophrenia patients (Weinberger and Berman, 1996).