System-specific differences in behavior regulation: Overrunning and underdrinking in molar nondepriving schedules.

Abstract

In two experiments we tested the molar regulation prediction that animals adjust schedule performance to reduce deviations from baseline response totals. Both experiments constrained the baseline drink-burst length under molar nondepriving schedules but allowed rats to continue running without drinking. In Experiment 1, rats were required to run in order to drink. In Experiment 2, water was delivered independently of running by fixed-time (FT) schedules. Under the run-to-drink contingency, rats exceeded their baseline amounts of running (overrunning) but failed to maintain their baseline water intake (underdrinking). The total amount of running that did not lead to drinking approximated baseline running. Under the FT schedules, rats again underdrank, but total running approximated baseline. These results do not support previous studies that have shown molar equilibrium effects under nondepriving reciprocal schedules. We conclude that (a) contingent running may not substitute for independent running; (b) intermittent access to water reduces the total instigation for drinking; (c) molar regulation differs under reciprocal and nonreciprocal schedules; and (d) more dynamic, system-specific regulatory models need to be developed.

Bliss points, stop lines, and performance under schedule constraint.

“…Thus, after both spouts became freely available during the contingency-paired test session, the rats contradicted the bliss point model by making too many empty licks—the same result seen in Experiment 2—and too few water licks, a significant shortfall not detected in Experiment 2. This shortfall resembled the underdrinking reported by Gawley (1986) for an experiment in which rats ran in an activity wheel for contingent access to water but received free access to water after various portions of the session had elapsed.…”

Responding Changes Systematically Within Sessions During Conditioning Procedures

“…Franklin and Quartermain (1970) studied rats licking (Experiment 1) or pressing levers (Experiment 2), with water as the reinforcer in both cases. The mean number of licks per 5-min interval remained approximately constant across 20-min sessions, but the number of lever presses increased (see also Gawley, Timberlake, & Lucas, 1987). Different schedules of reinforcement may produce different changes in responding.…”

Reinforcement in applied settings: Figuring out ahead of time what will work.

“…Other research has indicated complex interactions of schedule constraints with particular instrumental and contingent responses. Gawley et al (1986) and Gawley, Timberlake, & Lucas, (1987) found that slightly disrupting the drinking of rats significantly decreased their baseline intake, whereas forcing rats to markedly alter their pattern and amount of running in order to drink did not affect their free running (see also Tierney, Smith, & Gannon, 1987, and perhaps Allison, Buxton, & Moore, 1987). This is reminiscent of the tendency of Kavanau's (1963) deer mice to work to turn off a wheel that was rotating and turn on a wheel that was locked.…”