The role of response suppression in behavioral contrast: Signaled reinforcement

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Recent research on multiple schedule interactions is reviewed. Contrary to formulations that view contrast as the result of elicited behavior controlled by the stimulus-reinforcer contingency (e.g., additivity theory), the major controlling variable is the relative rate of reinforcement, which cannot be reduced to some combination of stimulus-reinforcer and response-reinforcer effects. Other recent theoretical formulations are also reviewed and all are found to face serious counterevidence. The best description of the available data continues to be in terms of the "context of reinforcement," but Herrnstein's (1970) formulation of the basis of such context effects appears to be inadequate. An alternative conception is provided by Catania's concept of "inhibition by reinforcement," by which rate of responding is inversely related to the average rate of reinforcement in the situation. Such a conception is related to Gibbon's recent scalar-expectancy account of autoshaping and Fantino's delay-reduction model of conditioned reinforcement, suggesting that a common set of principles determines several diverse conditioning phenomena. However, the empirical status of such a description remains uncertain, because recent evidence shows that schedule interactions are temporally asymmetric, depending primarily upon the conditions of reinforcement that follow a schedule component.

Section: Major Empirical Findings a The Independent Variable: Rementioning

confidence: 99%

Another Look at Contrast in Multiple Schedules

Williams¹

1983

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“…In several recent experiments (Reynolds and Limpo, 1968;Brownstein and Hughes, 1970;Brownstein and Newsom, 1970) behavioral contrast has been found to occur in one component of a multiple schedule when reinforcement availability in another component is signalled. According to the preference hypothesis, subjects should prefer (i.e., allocate more time to) non-signalled over signalled reinforcement in a concurrent choice situation.…”

Section: University Of British Columbiamentioning

confidence: 99%

SIGNALLED REINFORCEMENT IN MULTIPLE AND CONCURRENT SCHEDULES¹

Wilkie

1973

Five pigeons were exposed to multiple and concurrent variable-interval, variable-interval reinforcement schedules in which reinforcement availability in one component was never signalled. During certain phases of the experiment, reinforcement availability in the other component was signalled. Behavioral contrast was observed in seven of eight instances when reinforcement availability in the multiple schedules was signalled. Under the concurrent schedules in which reinforcement availability was signalled, the subjects did not always allocate more time to (prefer) the component containing non-signalled reinforcement, as would be predicted by an account of behavioral contrast holding that contrast results from the introduction of a less-preferred condition in one component of a multiple schedule.Despite several problems associated with defining behavioral contrast (see, for example, Bloomfield, 1969;Wilkie, 1971;Hemmes and Eckerman, 1972), the effect is often an increase in response rate in a constant or unchanged component of a multiple schedule that occurs when some change is made in the conditions prevailing in another component. Sev-eral investigators (e.g., Terrace, 1972) have pointed out similarities between behavioral contrast and phenomena such as "positive induction" (Pavlov, 1927), "frustration effects" (Amsel and Roussel, 1952), the "Crespi effect" (Crespi, 1944), and "transient contrast" (Nevin and Shettleworth, 1966).Much of the recent research on behavioral contrast has been concerned with determining what conditions in the altered component of a multiple schedule are necessary to produce contrast. Several hypotheses concerning the causes of behavioral contrast have emerged from this research. One hypothesis (Reynolds, 1961) is that a reduction in reinforcement frequency in the altered component is necessary to produce contrast; another (Terrace, 1966) is that a reduction in response rate in the altered component is necessary. Findings

“…This procedure typically reduces response rate if it is imposed on either variable-interval (VI) schedules (Brownstein and Hughes, 1970;Lander, 1971;Thompson and Corr, 1974;Wilkie, 1973) or fixed-interval schedules (Brownstein and Newsom, 1970). Further, since the interreinforcement interval is not affected, Brownstein and Hughes (1970) and Brownstein and Newsom (1970) have suggested that the signalled-reinforcer procedure provides a method of reducing response rate without concomitantly reducing frequency of reinforcement. Lander (1971) and Thompson and Corn, (1974), however, have proposed an alternative interpretation of the suppressive effects of signalled reinforcement.…”

mentioning

confidence: 99%

“…Further, Brownstein and Hughes (1970) and Brownstein and Newsom (1970) suggested that the signalled-reinforcer procedure produced contrast by reducing response rate in S-without a change in reinforcement frequency. The counter position, holding that signalled reinforcement segments a schedule into EXT and FR 1 segments, argues that both the suppression of responding in S-and the facilitation of responding in S+ are due to the imposed EXT condition.…”

mentioning

confidence: 99%

“…This procedure typically reduces response rate if it is imposed on either variable-interval (VI) schedules (Brownstein and Hughes, 1970;Lander, 1971;Thompson and Corr, 1974;Wilkie, 1973) or fixed-interval schedules (Brownstein and Newsom, 1970 signal is correlated with extinction (EXT). For example, if the signalled-reinforcer procedure is imposed on a VI schedule, it segments the schedule into EXT and fixed ratio 1 (FR 1) components.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Line‐orientation Generalization Following Signalled‐reinforcer Training

Griffin

Stewart

1977

Three naive and three nonnaive pigeons key pecked for food on a multiple variable-interval 1-minute variable-interval 1-minute schedule with a black zero-degree vertical line on a white surround associated with one component and a black line shifted 30 degrees to the right (+30 degree) associated with the other component. Subsequently, a signalledreinforcer procedure was introduced in the +30 degree component, i.e., whenever the reinforcer was available for the next response, the key changed to blank white. Following this training, the original unsignalled-reinforcer condition was re-instated. Line orientation generalization tests were given at the end of signalled-reinforcer training and after the second unsignalled-reinforcer condition. The signalled-reinforcer procedure reduced response rate in the +30-degree conmponent in all subjects but facilitated responding during the zerodegree component (behavioral contrast) for two of the naive subjects only. However, average generalization gradients following signalled-reinforcer training indicated peak shift in two subjects and area shift in all five subjects that completed the experiment. There was no apparent relation between contrast and peak shift or degree of area shift. The data were interpreted as supporting the notion that the signalled-reinforcer procedure segments a variable-interval schedule into extinction and fixed ratio 1 segments.Key words: signalled reinforcement, area shift, peak shift, behavioral contrast, key peck, pigeonsSignalled reinforcement refers to a procedure in which a signal occurs whenever the reinforcer will be produced by the subject's next response. This procedure typically reduces response rate if it is imposed on either variable-interval (VI) schedules (Brownstein and Hughes, 1970;Lander, 1971;Thompson and Corr, 1974;Wilkie, 1973) or fixed-interval schedules (Brownstein and Newsom, 1970 signal is correlated with extinction (EXT). For example, if the signalled-reinforcer procedure is imposed on a VI schedule, it segments the schedule into EXT and fixed ratio 1 (FR 1) components. That is, the unsignalled portion of the signalled VI schedule (SIGVI) functions like EXT because the reinforcer does not occur, and the signalled portion functions like FR 1 because the reinforcer always follows the response. Thus, although total reinforcement frequency remains unchanged, the relative frequency in the unsignalled portion of SIGVI is reduced to zero.The preceding account of the suppressive effects of signalled reinforcement also bears upon explanations of positive behavioral contrast. In the paradigmatic procedure for producing such contrast (e.g., Reynolds, 1961), one component (S-) of a multiple variable-interval variable-interval schedule (mult VI VI) is changed to EXT, which results in a decrease in response rate in that component. Contrast occurs if a concomitant increase in response rate is observed in the unchanged VI component (S+). Reynolds (1961)