Hyperthermia impaired human visual short-term memory: an fMRI study.

PURPOSE:In order to investigate the effects of hyperthermia conditions on human cognitive performance, functional magnetic resonance imaging (fMRI) was employed to investigate human brain activation during visual short-term memory (VSTM) tasks under modulated hyperthermia conditions. MATERIALS AND METHODS:A total of 38 right-handed healthy young male participants were randomly divided into control and hyperthermia groups who underwent VSTM tasks by using block design. RESULTS:Compared with that of the control group, the reaction time of the hyperthermia group was longer in VSTM tasks (p = 0.019), but there was no significant difference between the two groups for the accuracy rate (p > 0.85). The fMRI data showed that the processing advantage of the right hemisphere was notably enhanced and that activity strength of the bilateral dorsolateral prefrontal cortex and right intra-parietal sulcus were significantly enhanced in the hyperthermia group. CONCLUSIONS:These data provided neuroimaging evidence of the effect of hyperthermia conditions on the brain regions and also proved heat load decreases cognitive performance.