Maintenance schedules and hunger drive: An examination of the rat literature.

Abstract

In the interest of examining the possible relevance of the maintenance schedule variable, studies are reviewed in which the feeding method used to produce hunger drive was a manipulated variable and was not confounded with differences in body weight loss. In addition, a standardized notation system, capable of describing various maintenance procedures, was introduced and used in order to facilitate intra-and interexperiment comparisons. On the basis of the studies reviewed, it is concluded that (a) the maintenance schedule variable is a relevant one in the determination of behavior; (6) hunger drive is probably determined by some joint function of body weight loss and maintenance schedule; and (c) based on data currently available, some form of an adjusted percentage maintenance schedule appears to be the most appropriate for use in the study of rat behavior.

Theoretical, Practical, and Social Issues in Behavioral Treatments of Obesity

“…Studies by Baker (1955), Lawrence and Mason (1955), Mandler (1957), Gross (1968), and Weinstock (1972) all support the generalization that rats on irregular schedules behave as if they were operating on a higher level of drive than rats regularly fed and kept at comparable body weights. The more predictable food presentations are, the more time the animal has to engage in other activities; the most adaptive, i.e., energy-saving, activity would be sleep, because it is during sleep that energy expenditure is lowest.…”

Frustration and learned helplessness.

“…The subjects were 32 male Holtzman rats, 100-110 days old, weighing 286-317 g before deprivation. One week before the beginning of the experiment, all animals were placed on an 85% fixed body weight deprivation schedule (Weinstock, 1972). They were maintained on ad-lib water and were run during the light phase of the 12-hr dark/ 12-hr light housing schedule.…”

Inescapable shock interferes with the acquisition of an appetitive operant

“…The subjects were 24 male Holtzman rats approximately 90 days of age at the start of the experiment. One week before the experimental treatment, all rats were placed on an 85010 adjusted-body-weight deprivation schedule (Weinstock, 1972). They were maintained on ad-lib water and were run during the light phase of the 12-h dark/12-h light cycle.…”