Résumé
PURPOSE: To investigate the modifications in brain electrical activity (EEG) when performing a cognitive task in the heat. METHODS: 10 subjects performed a planning task (OTS: One Touch Stockings of Cambridge) with two levels of complexity: simple (OTS-4) and complex (OTS-6) after 2 hours of rest in hot (HOT, WBGT =40.2 + or -0.6[degrees]C.) and neutral (CON, WBGT =21.1 + or - 0.4[degrees]C) environments. RESULTS: Central temperature, was significantly higher in HOT (39.0 + or - 0.2) than in CON (37.0 + or - 0.2) condition. Independent of conditions, total alpha power (p<0.005) decreased from baseline to task engagement and theta power increased linearly comparing baseline to OTS-4 and OTS-6, respectively (p<0.05), suggesting theta activity increases with memory load and is a good indicator of working memory task demand.