Clonidine improves memory function in schizophrenia independently from change in psychosis. Preliminary findings

This study provides initial evidence that the alpha 2-adrenergic receptor agonist, clonidine, enhances memory functioning in hospitalized schizophrenics. Ten patients were tested while drug free and while on stable doses of clonidine (0.4-1.4 mg/day) for approximately 3 weeks. Throughout the duration of the study, all patients, as well as the examiner, were blind to medication status. Memory test scores were significantly better during the clonidine trials. This improvement occurred independently of change in psychosis. Clonidine does not improve memory in normal adults or in young and unimpaired animals, but has been shown to improve memory in Korsakoff's patients and non-human primates who are old or have dorsolateral prefrontal cortical lesions. The present results have implications for the role of the noradrenergic system in memory as well as for our understanding of the nature of the cognitive deficits associated with schizophrenia.