Hyperthermia does not alter the increase in cerebral perfusion during cognitive activation

•  What is the central question of this study? Decreases in baseline cerebral perfusion impair the capacity to increase cerebral perfusion during cognitive activation. Hyperthermia reduces baseline cerebral perfusion, but it remains unknown whether hyperthermia also impairs the increase in cerebral perfusion during the execution of a cognitive task. •  What is the main finding and its importance? This study shows that hyperthermia does not alter the increase in cerebral perfusion during a cognitive task. These findings have implications for individuals who are frequently exposed to heat stress in concert with a cognitive challenge.