Biology of Drives

Abstract

Claude Bernard and Cannon have shown that various physiological regulators serve the function of maintaining a constant internal environment. Richter''s exptl. work indicates that the animal as a whole also plays an important role in this regulatory function. These total responses are commonly overlooked in the intact organism, but by eliminating the physiological regulators in rats the author brought to clear definition the "total organism responses which serve to maintain a constant internal environment." Examples of these regulatory responses are the drinking of large quantities of water by rats when deprived of the mechanism for regulating water metabolism through surgical removal of the posterior lobe of the pituitary gland; the covering of the body with large amounts of nesting material when kept in a cool room after the regulatory mechanism for body temp. control has been abolished through removal of the pituitary or thyroid gland; and the intake of large amts. of minerals, carbohydrates and fats when the respective physiol. mechanisms for mediating the metabolism of these substances have been removed by operation. Further expts. with normal rats indicate that behavioral factors also play an important role in maintaining an optimal internal environment in the intact organism. When given an opportunity to choose their diet from as many as 15 different substances the animals arrived at a more efficient diet than had been devised by dietary experts. The implications of the homeostatic principle for the study of abnormal and psychotic behavior are briefly discussed.