Determinants of Pausing Under Variable‐ratio Schedules: Reinforcer Magnitude, Ratio Size, and Schedule Configuration

Abstract

Pigeons pecked a key under two-component multiple variable-ratio schedules that offered 8-s or 2-s access to grain. Phase 1 assessed the effects of differences in reinforcer magnitude on postreinforcement pausing, as a function of ratio size. In Phase 2, postreinforcement pausing and the first five interresponse times in each ratio were measured as a function of differences in reinforcer magnitude under equal variable-ratio schedules consisting of different configurations of individual ratios. Rates were also calculated exclusive of postreinforcement pause times in both phases. The results from Phase 1 showed that as ratio size increased, the differences in pausing educed by unequal reinforcer magnitudes also increased. The results of Phase 2 showed that the effects of reinforcer magnitude on pausing and IRT durations were a function of schedule configuration. Under one configuration, in which the smallest ratio was a fixed-ratio 1, pauses were unaffected by magnitude but the first five interresponse times were affected. Under the other configuration, in which the smallest ratio was a fixed-ratio 7, pauses were affected by reinforcer magnitude but the first five interresponse times were not. The effect of each configuration seemed to be determined by the value of the smallest individual ratio. Rates calculated exclusive of postreinforcement pause times were, in general, directly related to reinforcer magnitude, and the relation was shown to be a function of schedule configuration.

Rats don’t always respond faster for more food: The paradoxical incentive effect

“…Larger amounts of food often increase the postreinforcement pause (see, e.g., Harzem, Lowe, & PriddleHigson, 1978;Lowe, Davey, & Harzem, 1974), although in contrasted conditionsof reinforcement, smaller amounts of food may cause longer pauses, a negative contrast effect (Blakely & Schlinger, 1988). Hatton and Shull (1983) found larger feedings to presage longer pausing than did smaller feedings on fixed-interval schedules-but only when they were intermixed, not blocked.…”

Extended Pausing by Humans on Multiple Fixed-Ratio Schedules With Varied Reinforcer Magnitude and Response Requirements

“…This account predicts that increasing the frequency or magnitude of reinforcement should reduce pausing. Supporting data have come from research with fixed‐ratio (FR), fixed‐interval (FI), and variable‐ratio (VR) schedules (e.g., Blakely & Schlinger, 1988; Crossman, 1971; Felton & Lyon, 1966; Griffiths & Thompson, 1973; Inman & Cheney, 1974; Killeen, 1969; Lowe & Harzem, 1977; Powell, 1968, 1969; Rider & Kametani, 1984; Schlinger et al, 1990).…”

Fixed‐ratio Pausing: Joint Effects of Past Reinforcer Magnitude and Stimuli Correlated With Upcoming Magnitude

“…Moreover, this account predicts that manipulations to enhance response strength, such as increasing the frequency or magnitude of reinforcement, should reduce pausing. Supporting data come from research with FR, FI, and VR schedules (e.g., Blakely & Schlinger, 1988;Crossman, 1971;Felton & Lyon, 1966;Griffiths & Thompson, 1973;Inman & Cheney, 1974; Killeen, 1969;Lowe & Harzem, 1977;Powell, 1968Powell, , 1969Rider & Kametani, 1984;Schlinger et al, 1990). For example, Powell (1969) studied reinforcement frequency by manipulating FR size; as frequency was increased (by lowering the FR), pausing was reduced.…”