From the Veterans Administration Hospital, West

in physiological and emotional stress was established experimentally by Cannon and Mendenhall in 1914. It was later incorpo-rated by Cannon into his general theory of homeostasis. Other experimental work has in general substantiated these findings. More re-cently, de Takats has reported rapid coagula-tion of blood in man resulting from "fear, apprehension, and nervous strain. " Schneider has found that stress also shortens clotting time, the degree of change appearing to be proportional to the extent of elevation of the blood pressure. He observed this relationship to be of particular importance in patients with hypertension and with thrombophlebitis. The present study was designed to retest the relationship between anxiety and blood coagulation. A more precise quantitative in-strument was used, the Ultra Viscoson, which was adapted from industrial use by Yesner and Hurwitz for continuously measur-ing changes in viscosity during coagulation. In addition, we have made a gross compari-son in blood reactions to stress between psy-chotic and nonpsychotic patients. Some ex-perimental evidence has been published indicating that psychotics do not respond physiologically to stress to the same degree as nonpsychotics. Hoagland and other worker