The interaction of conditioned taste aversions and schedule-induced polydipsia: Effects of repeated conditioning trials

Abstract

In Experiment 1, rats poisoned following schedule-induced saccharin consumption showed a moderate reduction in the schedule-induced consumption of saccharin. With repeated poisoning, schedule-induced saccharin polydipsia was markedly reduced. Acquisition of conditioned aversion under the schedule-induced procedure was significantly slower than acquisition under water deprivation. In addition, recovery of consumption of the previously poisoned solution during extinction was more rapid under schedule-induced polydipsia. Experiment 2 revealed that schedule-induced polydipsia was less sensitive to suppression by conditioned aversions than a prandial drinking condition in which subjects were equally food deprived but were given a mass feeding instead of spaced pellet deliveries, suggesting that the relative insensitivity of schedule-induced polydipsia to conditioned taste aversions is not simply a function of different levels of food deprivation. This relative insensitivity is offered as a partial basis for the occurrence and maintenance of schedule-induced alcohol polydipsia.

The insensitivity of schedule-induced polydipsia to conditioned taste aversions: Effect of amount consumed during conditioning

“…Along with other work assessing the interaction of SIP and conditioned taste aversions (Clarke & Westbrook, 1978;Riley et al, 1980;Riley et al, 1979;Roll et al, 1969), the present results support the position that SIP is insensitive to conditioned taste aversions, an insensitivity which can in part account for the occurrence of the schedule-induced consumption of alcohol. …”

“…While the degree of the disruption in drinking was a function of the number of conditioning trials (cf. Nachman & Hartley, 1974;Riley et al, 1980)., the differences in the sensitivity of the two feeding schedules to taste aversions was evident at all levels of conditioning.…”

“…It has been suggested (Freed, Zec, & Mendelson, 1977;Riley et al, 1980;Riley et al, 1979) that the occurrence of schedule-induced alcohol polydipsia (Fa1k & Samson, 1975;Falk & Tang, 1977) is an index of the general insensitivity of SIP to conditioned taste aversions. This argument is based on the fact that although rats display SIP of alcohol, they will avoid the repeated consumption of intoxicating amounts of alcohol under ad-lib conditions in the home cage (Kulkosky, 1979;Kulkosky, Zellner, Hyson, & Riley, 1980;Samson & Falk, 1974).…”

“…Under SIP, for example, subjects typically consume at asymptote approximately 25 ml of water in a l-h session on a variable-time 6O-sec schedule of pellet delivery. Under 23.5 h water deprivation or following a mass meal of 60 pellets, subjects asymptotically consume, on the average, 12 and 5 ml of water, respectively (see Riley et al, 1980;Riley et al, 1979). Following asymptotic drinking under each of these procedures, on-baseline conditioned taste aversion training is initiated.…”

A reevaluation of the CS− hypothesis for schedule-induced polydipsia under intermittent schedules of pellet delivery

“…Falk (1961) demonstrated that if water is made continuously available to a rat leverpressing for food under an interval schedule, the rat develops a. characteristic temporal distribution of drinking following each pellet delivery (Staddon, 1977). Typically, this schedule-induced drinking occurs immediately following the delivery of food and greatly exceeds home-cage consumption under similar conditions of food deprivation (Riley, Hyson, Baker, & Kulkosky, 1980). While the majority of explanations of scheduleinduced polydipsia (SIP) have focused on physiological or motivational mechanisms (see Freed, Zec, & Mendelson, 1977;Roper, 1981), a Pavlovian conditioning account of SIP was recently presented (Lashley & Rosellini, 1980).…”