Tyrosine ameliorates heat induced delay in event related potential P300 and contingent negative variation

•P300 latency was significantly increased after heat exposure.•After tyrosine administration P300 latencies returned close baseline value.•There was a significant increase in M100 latency after heat exposure.•M100 latency was significantly decreased after tyrosine supplementation.•Reaction time significantly reduced after tyrosine administration. The efficacy of tyrosine, a catecholamine precursor, as a countermeasure in the reduction of cognitive decline during heat exposure (HE) using event-related potential P300, and contingent negative variation (CNV) was evaluated. Ten healthy males, age 20–30years participated in the study. Volunteers received placebo or tyrosine (6.5g) 90min prior to HE (1.5h in 45°C+30% RH). P300 latency was significantly increased (p