Cognitive deficits due to thermal stress: An exploratory study on soldiers in deserts.

Background: It is well known that environmental factors play an important role in human performance. High temperature and humidity particularly impair mental performance by altering brain neurochemistry and electrolyte disturbance which in turn affect one's overall efficiency. While the physiological responses to environmental heat have been well established, it is less clear about its impact on cognition. Study aims to investigate the impact of thermal strain on cognition.

Methods: One hundred (100) healthy soldiers aged between 20 and 30 years who had spent minimum of one year in desert conditions prior to their induction in the study formed sample of the study. The subjects were evaluated on memory and on cognitive functions twice i.e. in the month of February and June. The data so generated was analyzed by appropriate statistical methods.

Results: The mean age of the subjects were 25.8 yrs. There was a significant decline in cognitive performance in hot climate as compared to normal weather on Post graduate Institute (PGI) memory scale ( P  < 0.05). The effect was more marked for tests requiring sustained attention, concentration, psychomotor performance, verbal memory and tests of executive function.

Conclusion: The present study is the first study to be conducted in actual desert conditions. Findings revealed a detrimental impact of thermal stress on the cognitive performance of soldiers in deserts.