Variations in the Normal Electroencephalogram During a Five-Year Period

Abstract

During a 5-yr. period, numerous electroencephalograms (EEG) were made on 3 individuals, all [male] [male] who had been subjected to a variety of exptl. conditions. Their blood sugar and rectal temps. were also observed. There was no change in the gross appearance of control EEG which were obtained before and after recovery from the various experiences during the 5-yr. period. There was no variation in regularity nor any unusual waveforms or frequencies. The spread of mean frequencies for each individual was as follows: Subject. A, 8.8-9.6 cycles/sec.; Subject B, 8.3-9.3 cycles/sec; Subject C, 8.8-9.3 cycles/ sec. There was no consistent correlation between the daily fluctuations in mean frequency and in blood sugars. There was remarkably little change in mean frequency over a 5-yr. period. The results also give some indication of the reliability of this method of frequency analysis of the ERG.