Changes in self-stimulation preference as a function of incentive of alternative rewards.

Abstract

Rats on a 23-hr food and water deprivation schedule were tested for preference between lever pressing for electrical stimulation of the lateral hypothalamus and liquid rewards, which varied in taste and caloric content. Preference for self-stimulation diminished as the alternative liquid became more palatable: with a saccharineglucose solution as the alternative the animals showed an equal preference for hypothalamic stimulation and the liquid reward. In longer 6-hr tests, rats deprived of water for 24 and 48 hr initially showed a preference for self-stimulation over water but eventually satisfied their water deficit by pressing for water. Neglect of physiological needs during self-stimulation appears to be more a function of the alternatives available and the length of the test session than intrinsic properties of the brain stimulation.

Self-deprivation: A review.

“…A number of studies have demonstrated that some rats will self-starve when given simultaneous access to BSR and food (e.g., Routtenberg & Lindy, 1965;Spies, 1965). In addition, self-dehydration has been reported during water/BSR competition in thirsty animals (Falk, 1961;Morgan & Mogenson, 1966;Phillips et al, 1970). It is noteworthy that animals who self-starve will also self-dehydrate (Rossi & Stutz, 1978).…”

“…These more posterior placements, in an area more typically thought to be associated with sexual behavior (Caggiula, 1970), produced self-deprivation just as well as the more anterior sites. Phillips et al (1970), Stutz et al (1971), and Rossi and Stutz (1978) concluded that self-deprivation occurs because BSR is often more attractive than is the alternative reward. The following data have been used to support this conclusion which we refer to as the reward hypothesis.…”

“…It has been demonstrated that increases in either the train duration or current intensity of brain stimulation lead to increases in selfdeprivation Morgan & Mogenson, 1966) and BSR (Beyra, 1974;Deutsch, Roll, & Wetter, 1976). Phillips et al (1970) demonstrated that making the alternative to the BSR more palatable (e.g., by adding sucrose or saccharin to water) reduced the degree of self-deprivation. Consistent with this finding, increasing food and water deprivation decreased self-deprivation 39i Frank et aly in press;Morgan & Mogenson, 1966).…”

“…The rats' apparently maladaptive behavior was attributed to the activation of feeding-related neural mechanisms by the Requests for reprints should be sent to Robert A. Frank, Department of Psychology, University of Cincinnati, Cincinnati, Ohio 45221. brain stimulation and the subsequent short circuiting of normal regulatory behavior. An alternative explanation that was first offered by Olds (1956) and later by others (Phillips, Morgan, & Mogenson, 1970;Stutz, Rossi, & Bowring, 1971) characterized self-deprivation as the choice of an intensely rewarding stimulus over a less rewarding one. According to this view, self-deprivation does not involve a disruption of neural regulatory systems, but rather may be subsumed under the laws that govern more conventional choice behavior.…”

Competition and summation between rewarding effects of sucrose and lateral hypothalamic stimulation in the rat.

“…Much of the behavioral work addressing the relationship between rewarding effects of natural and electrically induced rewards can be categorized in terms of four types of measures: (a) the effects of deprivation on intracranial self-stimulation (Carr & Simon, 1984;Frutiger & Drinkwine, 1992;Hoebel & Teitelbaum, 1962;Margules & Olds, 1962;Rossi & Panksepp, 1992), (b) the effects of postingestional variables (e.g., stomach loading) on intracranial self-stimulation (Hoebel, 1968(Hoebel, , 1969Hoebel & Thompson, 1969), (c) competition between natural reinforcers and brain stimulation reward (BSR; Frank & Stutz, 1984;Miliaressis & Cardo, 1973;A. G. Phillips, Morgan, & Mogenson, 1970;Routtenberg & Lindy, 1965;Valenstein & Beer, 1962), and (d) summation between the rewarding effects of natural reinforcers and brain stimulation (Coons & White, 1977;A.…”