2011 Volume 9 Issue 2 Pages 189-195
In the present study was examined the occurrence pattern of the EEG in the 3-30 Hz frequency band with the development of the brain of infants.
Time series experiments were performed 3 times every 3 or 4 months on 3 infants ranging from 7 months to 15 months after birth. The EEG was recorded from 128 scalp locations. Music stimulation was used in the experiment.
1) For 5-9 months of age, ratios of the occurrence of the theta, beta, and alpha band, at the opening of eyes following rest, were 38%, 19%, and 43%, respectively. For 10-15 months of age, these ratios at the opening of eyes following rest, were 38%, 21%, and 41%, respectively. 2) For 5-9 months of age, the ratios of the occurrence of the theta, alpha, and beta band, at the music stimulation, were 41%, 18%, and 41%, respectively. For 10-15 months of age, however, these ratios at the music stimulation, were 29%, 18%, and 53%, respectively. The ratio of the occurrence of the beta band remarkably increased to 53% at 10-15 months of age, while the theta band decreased to 29%. The alpha band remained unchanged in the meantime. 3) The occurrence pattern of the EEG in the infants at 5-9 months of age developed the shape of vertical stripes in each hemisphere. However, such occurrence pattern of vertical stripes completely disappeared at 10-15 months of age, and, in contrast, the occurrence pattern of the beta band changed in the cerebral cortex hemisphere, beginning to move to all around directions. These results suggest that neuronal networks of the association area in infants become active from approximately 10 months of age with the development.
