[Neuromodulatory effects of caffeine and bromazepam on visual event-related potential (P300): a comparative study].

UNLABELLED The P300 component of the event-related potential (ERP) is a general measurement of "cognitive efficiency". It is an index of the ability of an individual's central nervous system (CNS) to process incoming information. OBJECTIVE To compare the neuromodulatory effects of caffeine and bromazepam on the visual ERP (P300), in relation to a P300 normative database. METHOD 15 right-handed individuals (7 male and 8 female), between 20 and 30 years of age, healthy, free of any cognitive impairment and not making use of psychoactive substances were studied. Participants were submitted to a visual discrimination task, which employed the "oddball" paradigm, after the administration of caffeine and bromazepam, in a randomized, double-blind design. RESULTS Statistically significant differences were observed when the caffeine and bromazepam conditions were compared to the normative database. CONCLUSION The present results suggest that caffeine and bromazepam have distinct modulatory effects on CNS functioning.