THE CORRELATION BETWEEN AGING AND ALPHA SLOWING
Teng Xiheng, et al Department of Neurology, Binzhou Medical College, Shandong Province
It is well known that the most frequent change seen in the EEG of old age is the slowing of alpha rhythm. As to the clinical significance of a slowing and where is its upper limit are still questions of controversy. By analyzing 509 cases of EEG of presenilc (182) and senile (327) cadres,we have found that there is a close negative correlation between aging and a slowing. By taking every half Hz as a frequency band since 8 Hz and taking those α frequencies≥10.5 Hz as one frequency band to observe the progress of α slowing, we've found that the curve of correlative coefficients is negative at the frequencies10 Hz and then being positive thereafter. The shifting point is at the α frequency band of 9.5—10 Hz. The curve of those over 60 years runs a similar way.It is by this observation we've suggested to take 9—9,5 Hz of α rhythm as the upper limit of a slowing and also taking this as a borderline EEG.