Application of the Spectral Analysis to Assess the Complex Sensorymotor Reaction of Workers at Nuclear Energy Facilities

Summary. The objective of the study is to determine the level of psychophysiological state of workers at nuclear facilities using an integral indicator calculated based on the spectral analysis of the results of the complex sensorimotor reaction (CSMR). To compare this indicator with the standard indicators contained in the current “Methodological Guidelines for Conducting Medical Examinations and Psychophysiological Surveys of Workers at Nuclear Facilities” of 1999 (MU-1999). To determine the boundaries of its normal fluctuations, defined as two standard deviations (SD) from the mean, and unacceptable values of this indicator.

Research materials and methods. Research materials – the results of the psychophysiological examination conducted in the laboratories of psychophysiological research in medical organizations of the Federal Medical and Biological Agency (FMBA of Russia) – 20 organizations and the Ministry of Health of Russia – 12 organizations in accordance with the order of the Ministry of Health dated July 28, 2020 No. 749n. In total, the analysis included the results of 6,085 examinations performed from 19.01.2021 to 07.03.2024. Distribution of the examined by gender: men – 5,423, average age (44.5 ± 0.9) years; women – 662, average age (41.3 ± 0.8) years. Research methods – the fast Fourier transform (FFT) method was applied to the SSMR results, implemented in the form of the authors’ own algorithm in the MS Excel environment with the calculation of the “Frequency density of signal power” (Pω) indicator, normalized to the number of SSMR stimuli in the form of the decimal logarithm Lg (Pωnorm).

Research results and their analysis. The results of the assessment of the SRMT using the standard indicators “Mean reaction time” (MRT) and “Root mean square deviation” from MU-1999 were obtained and compared with Lg(Pωnorm). A stronger correlation of the Lg(Pωnorm) indicator with both MRT and SD was revealed than between these indicators. Statistically significant differences in this indicator with changes in the SRMT were established; its upper and lower limits of the norm, equal to 3.63 to 4.83 logarithmic units, and their unacceptable values were determined.

Conclusion. The study provides a rationale for the relevance of research in the field of development and improvement of indicators for assessing the functional state of the central nervous system of subjects using the mathematical apparatus of the FFT. Based on the data of 6085 examinations, a new integral indicator Lg(Pωnorm) was proposed, a method for its calculation was given, and its standard values were determined.