Electroencephalographic, hormonal, and psychiatric investigations of a small number of subjects with and without premenstrual tension have revealed the following :(1) no indication that the behavioral manifestations of premenstrual tension reflect directly alterations in the cerebral neurophysiology so measured, (2) endocrine activity within normal limits in all subjects, with no demonstrable distinction between subjects with premenstrual tension and controls, and (3) no evidence that would substantiate a theory of psychogenic etiology for premenstrual tension.However, there appeared to be some definable differences in behavior other than the premenstrual manifestations differentiating the 2 groups. The subjects with premenstrual tension showed more marked emotional lability throughout their cycles, and in general were less assertive individuals.Abstract Teaser