[Stress reaction to work today]. / Reaktsiia na stres pri suvremenniia trud.

The characteristic of stress factors at work and their effect upon humans is of great significance in labour optimization, detection of early changes in organism, assessment of the operative MAC and MAN, standardization and categorization of labour, etc. On the base of such studies (biochemical, physiological and psychophysiological) stress and fatigue in various occupations and working regimes are characterized. The results from the studies on stress reactions at work are presented in a summarized way, making use of complex methodical approach.

Diurnal variations in the cortical visual and auditory evoked potentials.

Visual and auditory evoked potentials (VEP and AEP) have been recorded for six subjects during the day (11.00-12.00 h) and during the night (23.00-24.00 h). For each subject the following parameters were estimated separately: the confidence limit of the averaged EP, the mean value and the standard error of the latencies of the EP components, EP energy and the product-manner correlation coefficient to evaluate waveform similarity of two evoked potentials. In order to estimate the diurnal variations of VEP and AEP, a comparison is made for each subject separately of the amplitudes and latencies, and their dispersions at N100, P200 for VEP and N100, P200 and P300 for AEP during the day and during the night. During the night hours the amplitudes of the different components and the EP energy are found to increase. The variativity of VEP and AEP increases during the night, while the degree of EP similarity and especially of their late components, decreases. The symmetry of the interhemispheric distribution of VEP, estimated by the peak amplitudes and the energy during the night hours of investigation, is disrupted.