The Behavioural Response of Infants to Heat Stress *

The influence of environmental temperature on the water and electrolyte balance of infants has been studied by Cooke, Pratt, and Darrow and reported in this journal.8 However, changes in the feeding behaviour and activity of infants exposed to heat stress have not been extensively studied. The suppression of food intake in adults by high environmental temperature has been known for years," but the influence of psychic factors in adults complicates these results. In the laboratory the relationship between food and water intake and environmental temperature has been studied in several species2' " 18,16 with fairly consistent lowering of the food intake with heat stress. The human infant is in many ways comparable to the laboratory animal in being relatively free of habit and prejudice. Therefore, a study of the feeding behaviour of infants may be of value in understanding the physiological mechanisms underlying the regulation of food intake in the human species. It is the purpose of this paper to report the influence of environmental temperature on the food and water intake of human infants. A few other somewhat unrelated effects of environmental temperature on their behaviour will be mentioned.