CHANGES IN ELECTROENCEPHALOGRAM (EEG) POWER DURING SUBDOMINANT (LEFT) HAND FINGER MOVEMENTS IN FEMALES WITH DIFFERENT ALPHA RHYTHM CHARACTERISTICS

Background
This study investigates the indicators of electroencephalographic (EEG) oscillatory activity and processes that are correlated with manual movements executed by the subdominant (left) hand in women with a high or a low individual α-frequency.

Material and methods
113 healthy right-handed women from the ages of 19 to 21 were divided randomly into two experimental groups with high (n = 59, IαF > 10.25 Hz) and low (n = 54, IαF ≤ 10.25 Hz) individual EEG α-frequency (IαF). EEG power during flexion or extension of the subdominant hand fingers was evaluated.

Results
Manual movements performed by women, especially those exhibiting high modal α-frequency, were accompanied by reduced α and β power in mid and posterior cortical areas. These changes occurred in combination with a local power increase in α1-oscillations in the frontal leads. A local increase of α3-activity in the frontal cortex areas was also revealed in women with low IαF. In this same group of women, generalized increases in EEG power of θ-, β- and γ-oscillations were observed in the cortex.

Conclusions
These results revealed a greater redundancy of brain processes in women with low IαF power compared to women with high α-frequency.