Electrical activity of the cerebral cortex during the low-frequency acoustic stimulation in women with different characteristics of alpha rhythm

Abstract

Background: Human functional capabilities, to a certain extent, depend on an individual’s nervous system. The recording of the spontaneous electroencephalogram (EEG) makes it possible to estimate specific features of the nervous system, and in particular the activity of the human brain. Purpose: This study is aimed at investigating the brain in women with a high or a low individual α-frequency (ІαF), determined in a quiescent state during low-frequency acoustic stimulation. Methods: The study group consisted of 113 right-handed healthy women in the age group 19-21 years. The study group was divided into 2 categories in terms of the average magnitude of ІαF - groups with high (n = 59, IαF ≥ 10.25 Hz) and low (n = 54, IαF ≤ 10.25 Hz) values of ІαF. The power and coherence of electrical activity of the cerebral cortex as well as the differences between the groups were evaluated in a quiescent state during low-frequency acoustic stimulation. Results: In case of low-frequency acoustic stimulation, a high rate of EEG θ-, β2-power, γ-waves in thecortex, α1-oscillations - in frontal areas were registered in women with a high α-frequency, while the power α2-, α3-and β1-activity became lower in the cortex. Women with a low α-frequency had a decrease of the cerebral cortex α-θ-, α- and β-activity. This was recorded as more generalized, and the expression of γ-waves was more localized. All the participants had increased values of coherence of the EEG frequency components in the cortex. Some overexertion on the right side was detected in the right hemisphere posterior structures. Some local reduction of the coherence of θ-, α1-, α3-oscillations was found in women with a high α-frequency and α1-activity among the study group members with a low α-frequency in the frontal and anterior temporal areas. Conclusion: The establishment of common factors in the study group is an important step towards defining clear prognostic criteria for the physiological capabilities of people based on the congenital features of brain function.