Activity in Starvation †

Deprivation of food, water, or individual nutrients usually causes an increase in the spontaneous running activity of the rate 9"'0, 170 2, U t, 2#,a8 although some exceptions have been reported.2,'7' ' The measurement of running activity has been used for investigations into motivation, for instance, as a measure of the hunger and thirst drives."90" Wald and Jackson considered the hyperactivity of rats during nutritional deprivation an example of mammalian emigration to relieve the nutritional pressure on the home population. On the other hand, muscular activity is one of several means by which body temperature can be maintained through an increase in heat production.", 7 24 If the increased activity during starvation primarily reflects some function in the maintenance of body temperature, then there should be a relation between the environmental temperature and the degree of activity in starvation.