I N 'rHE past, mental deterioration was considered inevitable in the lifehistory of the epileptic, with possibly a few exceptions in which the epilepsy was naively regarded as part and parcel of genius, since it appeared in individuals with marked creative talents; viz., Caesar, Flaubert, Dostoevsky.Present day studies show differences of opinion with regard to the inevitability of deterioration. Fetterman and Barnes, (1) for example, found no decided trend toward deterioration for 46 hospital dispensary patients, nor any direct connection between intelligence quotient and the nature of the attack or duration of the disease. Sullivan and Gahagan (2) found much variability and less deterioration than most writers on the subject. Patterson and Fonner (3) found much variation and deterioration, and a great proportion of patients were classifiable as feebleminded among their institutionalized epileptic children. The deterioration, however, was found to be unrelated to frequency and severity of seizures. Dawson and Conn, (4) on the other hand, in a study of epileptic children found definite evidence of deterioration which they' attributed to epilepsy, with no significant relationship between the degree of deterioration and duration, but a significant correlation between decrease in the frequency of attacks and mental progress.The tendency among students of epilepsy at the present time is to differentiate quite sharply between institutionalized and non-institutionalized epileptics. It has been estimated that the former are on the average 10 to 15 points lower in IQ than the latter, and present a more striking picture of mental deterioration. Adequate data to support this contention, however, are absent from the literature.As a segment of a broader study, planned to deal with the social and psychological factors characterizing institutionalized epileptics, this paper raises the following questions. First, do institutionalized epileptics deteriorate, and to what extent, as compared with non-institutionalized epileptics? Second, do any significant relationships suggest themselves between change in intellectual status and the nature of the attacks, especially with regard to severity and frequency?• Read before the Midwestern Psychological Association, May 4,1940, Chicago, Illinois. The writer is indebted to Dr. Andrew W. Brown whose helpful guidance and encouragement made this study possible. The research was carried on through the facilities of the Dixon State Hospital.