The influence of chronic psycho-emotional stress on cognitive function

Aim. The influence of the chronic psycho-emotional stress on the cognitive function was studied.

Methods. 160 railroad engineers of main-line locomotives, whose occupation is acknowledged to be one of the most stressful, were examined. 100 healthy volunteers were examined as a control group. A scale of psychological tension PSM-25 was used to evaluate the effect of the stress. Neurohumoral response to stress was studied by the activity of the hypothalamic-pituitary-adrenal axis, defining adrenocorticotropic hormone, cortisol and corticosterone concentrations. Cognitive functions were examined by the neuropsychological tests: Schulte tables, F. Grobov tables, Burdon correction tests. Attention assessment was emphasized due to railroad engineer’s profession specifics. Result. The reaction of the hypothalamic-pituitary-adrenal axis depended on the duration of chronic psycho-emotional stress: resistance period with reduced levels of the stress hormones in the next 5-7 years replaced the period of activation in the first years (with increased production of adrenocorticotropic hormone, cortisol and corticosterone). The reactivation of the hypothalamic-pituitary-adrenal axis occurred after 12-15 years. Neuropsychological tests revealed that the effect of chronic psycho-emotional stress was accompanied by decreased cognitive functions compared to controls. Time for passing the tests and the number of errors increased, productivity, stability and attention concentration dropped. The term of cognitive function disorders onset and their severity depend on chronic psycho-emotional stress duration. The extract of Ginkgo biloba (EGb 761, 240 mg per day for three months) intake has significantly improved the results of neuropsychological retests.

Conclusion. Chronic psycho-emotional stress leads to deterioration of cognitive functions, and, in particular, attention. The use of Ginkgo biloba (EGb 761) extract is rational for treatment of cognitive malfunction.