their help and cooperation. We are especially in-

the perception of a fearful object, can evoke autonomic changes. The inverse of this opera-tion—the influence of autonomic upon psy-chologic activity—is, however, poorly under-stood. At the turn of the century Eppinger and Hess gave their answer in terms of sympathi-cotonia and vagotonia, but this suggestion has been found unsatisfactory.31'45 Wenger's careful work has produced a more tenable modification of the Eppinger-Hess concepts, but the basic personality correlates remain similar. He found a positive correlation be-tween sympathetic predominance and de-creased emotional inhibition, decreased dom-inance, increased activity, increased emotional excitability, and increased suggestibility. His measure of autonomic balance has been criti-cized,81 and we cannot tell from his approach whether he was observing the effects of auto-nomic balance on personality or the effects of personality traits on autonomic activity. We From the Naval Medical Research Institute, Bethesda, Maryland. The opinions expressed in this paper are those of the authors and do not necessarily reflect the views of the Navy Department. The authors wish to express their appreciation to the staffs of the Naval Medical Research Institut