Electroencephalographic Changes and Vigilance Behavior During Experimentally Induced Intoxication with Alcoholic Subjects

Spectral analyses of EEG data derived from 12 healthy male alcoholics are reported. Data were acquired at five blood alcohol levels ranging from.026% to.104%. Marked increases in 8- and 9-cycle activity were accompanied by sub-stantial reduction of 10- and 11-cycle energy with no change in the 12- and 13-cycle activity. This confirms previous reports of "alpha slowing " under alcohol. (Frequencies slower and faster than those mentioned above were not significantly altered.) There was a marked increase in alpha abundance with maximal change induced by very light alcohol dosage. Increases in heart rate were highly cor-related with dosage and are believed to be covariant with changes in peripheral blood volume. Rapid eye movement activity was markedly enhanced by the alcohol doses employed. In a separate study, 13 male alcoholics were given 0.5 ml./kg. of ethyl alcohol prior to being tested over a period of about 50 min. on an auditory vigilance task requiring detection of infrequent (2/min.) variations in the temporal pattern of "click " stimuli. On control days, without alcohol, the expected decrement in signal detection over time was noted. However, with alcohol this decrement did not occur. Signal detection differences between control and alcohol days were statistically significant when blood alcohol was lowest near the end of the vigi-lance run. I H E LITERATURE relating to the ef- grams (EEGs) may justify the follow-fects of alcohol on electroencephalo- ing summary statements: (1.) alcoholics From the Department of Psychiatry, The without psychoses do not show EEG Neuropsychiatric Institute, University of Call- patterns of clinical significance1'2 (2.) fomia, Los Angeles, Calif. One report2 indicates that alcoholics Grateful acknowledgment is given to the h a y e, , fc. d # fa