Heat Regulation in Dementia Præcox Reactions of Patients with Dementia Præcox to Cold.

THE responses of a homoeothermal organism to an extremely low environmental temperature and their adequacy in maintaining the body temperature at its normal level are measures of heat regulatory efficiency. A study of the reactions of schizophrenics exposed to extreme cold may reveal defects of aetiological importance. Experiments on heat regulation are particularly applicable for the discovery of any inadequacies in dementia precox at the physiological level because the stimulus (cold) may be made sufficiently intense to tax the central thermogenetic apparatus to the utmost. Lavoisier,' in 1777, observed that a man consumes more oxygen when the temperature of the air is 150 C. than he does when the environmental temperature is 32.50 C. Rubner,2 among others, has demonstrated by calorimetric experiments that the heat production of the body is increased when there is a fall in the external temperature, the body temperature remaining constant. This phase of heat regulation was termed by Rubner 'chemical regulation' in contradistinction to 'physical regulation' which consists in an adjustment of the heat loss of the body when exposed to ordinary environmental temperature changes. Chemical regulation consists of a reflex increase in heat production in response to a very low external temperature when physical regulation or diminution of the heat loss no longer suffices to maintain the body near its constant temperature. Variations from the normal in the oxygen consumption rate of schizophrenics have been reported by Hoskins.3 However, the lower oxygen consumption rate under basal condition that he reported may be interpreted as being due to the inactivity of the schizophrenic or may be consequential to the disease, a factor which Hoskins did not omit in his interpretation. On