Changes in hunger during starvation

Gradients of drive stimulus (Sd) intensity generalization.

“…This suggests that the effects of extinction are to a certain degree specific to the intensity of the drive stimulus operating during extinction. The motivation curves obtained by Heron and Skinner (5) and Perin (14) tend to indicate that stimulus-intensity generalization also operates in the case of reinforcement effects.…”

Drive (D) as a function of hours of hunger (h).

“…For example, in the studies by Warden et al (11) changes in obstruction grid crossings were produced by varying the hours of food, sex, or water deprivation. By a reconditioning procedure, Heron and Skinner (3) determined the relationship of rate of unreinforced responses to days of hunger. Also in the experiments by Williams (15) and Perin (9), recently expanded by Koch and Daniel (8) and Saltzman and Koch (10), intensity of motivation was varied by varying the number of hours of food deprivation, and approximations to measures of reaction potentiality were obtained by extinguishing the conditioned Skinner box lever-pressing response.…”

Hunger

“…• When albino rats were starved, the drive for food increased steadily from the first day until a point when their search activity decreased abruptly. This breaking point was extremely variable, in a range from the 4 th to the 15 th day with no indication of which variables could predict it (Heron & Skinner, 1937). • Once the breaking point was reached, it was almost impossible to recover the animal.…”

“…• Once the breaking point was reached, it was almost impossible to recover the animal. It would always die whatever actions were taken to heal it (Heron & Skinner, 1937). • When albino rats were starved collectively, hunger did not increase hostile or aggressive attitudes among them.…”