EFFECTS OF CAFFEINE ON VISUAL EVOKED POTENTIAL (P300) AND NEUROMOTOR PERFORMANCE

ABSTRACT- The stimulant effects of caffeine on cognitive performance have been widely investigated. The visual evoked poten-tial, specially the P300 component, has been used in studies that explain the stimulant mechanisms of caffeine through neurophys-iological methods. In this context, the present study aimed to investigate electrophysiological changes (P300 latency) and modifi-cation of cognitive and motor performance produced by caffeine. Fifteen healthy volunteers, 9 women and 6 men (26 ± 5 years, 67 ± 12.5 kg) were submitted three times to the following procedure: electroencefalographic recording, Word Color Stroop Test, and visual discrimination task. Subjects took a gelatin caffeine capsule (400 mg) or a placebo (P1 and P2), in a randomized, crossover, double-blind design. A one-factor ANOVA and Tukey ’ post hoc test were used to compare dependent variables on the C, P1 and P2 moments. The statistical analyses indicated a non-significant decrease in reaction time, Stroop execution time and latency at Cz on the caffeine moment when compared to the others. Moreover, a non-significant increase in Stroop raw score and latency at Pz could be observed.The only significant result was found at Fz.These findings suggest that the positive tendency of caffeine to improv