No abstract

and the late P. A. DAVIS, M.D.I N 1937 we published a brief note (10) describing two major correlations between the electroencephalogram (EEG) and the psychologic organization of the individual. The psychologic formulations were based on psychoanalytic data and other information available on 66 patients at the Institute for Psychoanalysis in Chicago. From 1937 through 1940 we obtained annually additional EEG records (with improved technic) on as many as possible of the original group and also on nearly one hundred additional individuals who have been in psychoanalysis. Our two original correlations have been confirmed and the concepts clarified by this subsequent study, and in addition a third correlation has been established. The present paper aims to present these correlations as empirical propositions, with a minimum of theory and interpretation. EEG Procedure and DefinitionsThe descriptive classification of the EEG patterns by P. A. Davis (5) distinguishes three main types among the usual normal records. These are the A type with regular alpha rhythm, the B (low-alpha, low-voltage type, referred to by some authors as "beta" type), and the M, MF, and MS, (P.A.D.), and wartime service with the U. S. Navy and the NDRC respectively for the other two. We have made no attempt to add references to later work in electroencephalography although much might legitimately be mentioned. We have also adhered with slight modifications to the concept of "types" of EEG pattern developed by P. A. Davis although we hope that in the future a more quantitative and less impressionistic set of concepts may be substituted for them. or "mixed" types. The mixed group is characterized primarily by the generally irregular appearance of the record and the prominence of frequencies other than the smooth alpha waves and the small fast beta waves of the A and B records. The general tempo of the MF record is faster than the 10.5 per second which represents the center of the usual alpha frequency range, and the dominant tempo of the MS record is slower than this. M records show prominent waves both faster and slower than 10.5 per second. The MF and the A types have proved to be the commonest in a number of different samples of the population, for example, college students, medical students, aviation cadets, friends and acquaintances of the authors, and the same distribution is found in the present series.Our records were all recorded by means of an ink-writing oscillograph (Grass), using scalp to ear-lobe connections. Solder-pellet electrodes were attached with electrode paste and collodion at standard positions on occipital, precentral and frontal regions (5). In 1936 only two placements (occiput and vertex) and a one-channel instrument were employed, but later three, six, and finally nine placements, and a two-and then, in 1939 and 1940, a three-channel instrument were used. The subjects lay comfortably on a cot with eyes closed in a moderately lighted room. Every effort was made to make them comfortable and relaxed, both physically and psyc...