IT WAS postulated on the basis of recent investigations,1-4 that there may be some defect in the ability to process information in a wide variety of psychiatric diseases which might be correlated with differences in the stimulus bound electrical activity of the brain. Exploratory studies in our laboratory justified further investigation in this area.5 Input-output relationships were investigated for patient and nonpatient groups using flashes of light as discrete units of information.
Subjects.—The Nonpatient Control Group: This group consisted of 41 members of the professional and clerical staffs of St. Elizabeths Hospital and of the National Institutes of Health. All had normal electroencephalograms (EEG). Ages ranged from 20 to 60 years.The Patient Group: This group consisted of 71 patients from St. Elizabeths Hospital. New admissions to the William A. White Service were tested as a routine part of their admission evaluation. No