Coherence of EEG Frequency Components While Performing Alternative Finger Movements in Women with Different Modal Frequency of Alpha-rhythm

Abstract

A test group consisting of 113 right-hand healthy women from the ages of 19 to 21 was divided into two groups according to the average magnitude of their individual modal αfrequency -groups with high and low values of individual modal αfrequency. The ideal time of a simple sensorimotor reaction and choice-point behavior as well as speed capabilities of nervous processes during the tapping test, and measures of the coherence of EEG frequency components individually determined for each testee in quiescent intervals and while performing alternative movements by the right hand fingers were evaluated. Women with high modal α-frequency had better speed capabilities of nervous processes. Women with a high IαF had a less time of simple and complex reactions. The increase of coherence coefficients was seen throughout the EEG frequency spectrum in women performing alternate movements by fingers. Alternate movements of fingers performed by women with low α-frequency are provided by even higher frequency coherence of the EEG components in frontal, anterior temporal and central areas and by much lower frequency in the posterior temporal and parietal-occipital cortex areas compared to testees with high α-frequency.Formulation of scientific problem and its significance. Movements by the upper extremities, particularly but not exclusively, by human fingers, form the basis of the manual movements in any labor activities. This or that person's individual functional capacities of the motor system acquire the critical score for a successful learning of a wide range of trades in the present-day society. For this purpose, an academic community places greater emphasis on issues dealing with the personality traits of the cerebral processes guaranteeing the motorial programming of the manipulation movements (MM).Analysis of studies of the problem. Various aspects of the abovementioned problem were studied in the area of neurophysiology concerning motor activities [1][2][3][4][5][6][7][8]. MM are obviously associated with the significant alterations of the brain activities ensuring the formation of the appropriate motor programs and orders. However, any specific information concerning these processes in the cerebral cortex is still very limited. It is not improbable that certain performance measures of the cerebration being correlated with MM -their amplitude, speed and accuracy are existed.Scientists [9][10][11][12] found out that individual values of the amplitude-frequency characteristics of any α-rhythm, including the modal frequency of such a rhythm demonstrate a significant informational content in determining the state of the main physiological functions of the man. According to the data of Bazanova [9], Kristeva, Charakov, Losch et al. [12] the ideal coordination of processes organizing movements and capacity for the censorship are positively correlated to the power of the individual EEG αrange and negatively to the tension of the muscles of the facial expression (forehead) being inactive during the MM autocinesia. These statement...

Changes in Electroencephalogram (Eeg) Power During Subdominant (Left) Hand Finger Movements in Females With Different Alpha Rhythm Characteristics

“…According to the available results, examinees with initially high EEG α-rhythm modal frequency had higher levels of selective attention and more local changes in electrical activity of the cerebral cortex during the regulation of MM. People with a low α-frequency were characterized by less specific and differentiated cortical activation processes [20,21,23]. The functional differences previously identified in men during their performance of MMs by the subdominant hand [22] may reflect a generally relatively lower tone of cortical activation in men with a low IαF that can be specifically compensated for by increased "intensity" and an observed redundancy of brain processes.…”

“…The nature of responses in the survey and execution of the motor and psychoacoustic tests were determined. The individual profiles of the manual motor asymmetry as well as auditory asymmetry were counted for each woman (K skew) (Formula 1) [20][21][22][23][24].…”

“…Changes in electroencephalogram (EEG)... Further studies involved dextral examinees whose coefficients of manual and auditory asymmetries were positive and were above 50% [21,22]. There was a total of 113 female subjects.…”

“…Kristeva et al [12] noted that an increment of the EEG α-amplitude and a decrease of the integral power of the facial muscle electromyogram can be considered as an increase of the ability to self-control movement. It should be emphasized that the modal α-frequency of EEG is often considered [13][14][15][16][17][18] as a sign that reflects important innate features of the structural organization of thalamic and cortical neurons, in particular, the features of ionic processes in these cells [19][20][21].…”

“…Taking into account the exceptional importance of the results obtained by various scientists, we have to note some insufficiency of such information to fully understand how the modal frequency of the EEG α-rhythm can be related to the control of the activity of the distal muscles of the hand. Previous studies [20,21,23] showed the brain processes' features during execution of manual movements in men with different modal frequency of EEG alpha rhythm. According to the available results, examinees with initially high EEG α-rhythm modal frequency had higher levels of selective attention and more local changes in electrical activity of the cerebral cortex during the regulation of MM.…”