Pausing in multiple fixed- ratio schedules

Abstract

Pigeons were maintained on multiple fixed-ratio schedules with food reinforcement for a keypeck response. A regular pattern of short-short-Iong-Iong-etc. was employed for the fixed-ratio sequence within a session. Pausing following reinforcement was shown to be determined by the length of the forthcoming fixed ratio. the relation of this fixed-ratio length to the schedule paired with it. and the place of the fixed ratio in the patterned sequence. The sequential effect indicated shorter pauses for a given fixed ratio when its completion would be followed by the shorter fixed ratio. and longer pausing at the point of transition from a shorter to a longer fixed ratio.The performance generated by a particular schedule of reinforcement can be influenced by other schedules in the total test situation. These schedule interactions (Reynolds, 1961a, b) indicate that relations among conditions of reinforcement are important in determining the performance generated by each individual schedule in the set of procedures employed. Nevin and Shettleworth (1966), Pliskoff (1961Pliskoff ( , 1963, Staddon (I 969), and Wilton and Gay (1969) have all produced evidence that the pattern or sequence of schedules contributes to interactive effects. Enhanced effects or schedule interaction have been shown at the point of schedule change (Azrin, 1960) or interface of stimuli related to differenl schedules (Catania & Gill, 1964).Effects in postreinforcement pausing on fixed-ratio (FR) schedules related to the sequence of schedule presentation have been demonstrated by Mintz, Mourer, and Gofseyeff (1967). In the multiple FR schedules they employed (FRs of different length, each distinctively cued), the pause duration related primarily to the length of the forthcoming FR. Interaction manifested itself in differences between pausing following changes to, as opposed to repetitions of, a given FR. The present study extends this earlier investigation to quantitative manipulation of FR length. The analysis is aimed both at a clearer formulation of the determinants of FR pausing and a further examination of how the specific context contributes to schedule interaction. METHOD SubjectsTwo mature male white Carneaux pigeons were used as subjects. Both were maintained at 80% of their free-feeding weights. Both were experimentally naive prior to the study. Water was continuously available both in the home cage and the test environment. A standard grain mixture of 50% kaffir, 40% vetch, and 10% hemp was used for reinforcement.This research was supported in part by a grant from The City University of New York Faculty Research Program. Requests for reprints should be sent to Donald E. Mintz, Department of Psychology, City College of New York, New York 10031. ApparatusA Lehigh Valley two-key operant chamber for pigeons (Model 1519-2) was used, with only the right-hand key in operation. A force of approximately .15 N was required to operate the key. White noise was provided to mask apparatus sounds. The measurement of time intervals reported was accompli...

The effects of time-out duration during fixed-ratio reinforcement

“…This period of time , during which no responses are made on the operandum, has been termed the post reinforcement pause (prp), preresponse pause (prp) , pause after reinforcement (par), or ratio break, and its duration has been reported to be a function of the length of ratio (Boren, 1953;Felton & Lyon, 1966;Ferster & Skinner, 1957;Powell, 1968). In studies employing multiple FR schedules, where the impending contingency is exteroceptively cued, the ratio pause appears to be a function of both the ratio just completed and the present ratio (Griffiths & Thompson, 1972;Mintz, Mourer, & Gofseyeff, 1967) or forthcoming ratios (Mintz, 1976).…”