Comparative analysis of bioelectric activity of the brain of ambulance station personnel before and after daily duty

Introduction. The adaptive overload of the central nervous system, caused by occupational stress, leads to the disruption of complex operational activities in the ambulance station workers and an increasing number of errors in medical decision-making towards the end of the work shift.

Aim. To assess the level and prevalence of changes in the work of the central nervous system (CNS) under the influence of occupational stress.

Materials and methods. The study involved 35 workers (medical and nursing staff) of ambulance station (19 men and 16 women aged 20  to 55  years). Electroencephalogram (EEG) was recorded at rest for  3  minutes, according to international scheme 10-20  in  six leads: F3, F4, T3, T4, P3, P4. The  following rhythmic activity indicators were used: THETA  rhythm (4–8  Hz), ALPHA rhythm (8–12 Hz), BETA rhythm (BETA, 12–25 Hz) and their ratios.

Results and discussion. When analyzing the overall activity, there is a decrease in all the studied parameters. At the same time, THETA, BETA and the total power of all ranges showed significant dynamics. In spatial analysis, the most noticeable decrease in activity in the frontal lobes (F3, F4) is responsible for motor behavior (premotor area of the cortex), executive functions (behavior control, inductive reasoning, planning), short-term and spatial memory, attention (spatial and motor). The decrease in activity in the temporal (T3, T4) and parietal (P3, P4) departments is observed only in some indicators.

Conclusions. Professional workload during the 24 hour shift has a predominant effect on the activity of the frontal lobes, reducing the ability to control and plan complex (precise) motor functions, visual-spatial attention and planning abilities. These mechanisms are key to the professional work of the personnel of the emergency medical service and determine the number of errors. 

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