individuals with developmental disabilities
A review of “noncontingent” reinforcement as treatment for the aberrant behavior of
individuals with developmental disabilities
James E. Carr*,1, Sean Coriaty, David A. Wilder2, Brian T. Gaunt3, Claudia L. Dozier4, Lisa N. Britton5,
Claudia Avina, Curt L. Reed University of Nevada, Reno, NV 89557-0062, USA
Abstract
The term noncontingent reinforcement (NCR) refers to the delivery of an aberrant behavior’s known reinforcer on a response-independent basis. The typical result is a decrease in responding from baseline (i.e., reinforcement) levels. NCR has become one of the most reported function-based treatments for aberrant behavior in the recent literature. The purpose of this review is to briefly discuss the history of the procedure and summarize the findings from the treatment research literature. The review is organized into the following sections: (a) basic research on NCR, (b) NCR as a control procedure, (c) NCR as a function-based treatment, (d) considerations in the programming of NCR schedules, (e) behavior-change mechanisms underlying NCR effects, and (f) directions for future research. © 2000 Elsevier Science Ltd. All rights reserved.
1 James Carr is now at Department of Psychology, Western Michigan University, 1903 W. Michigan Ave., Kalamazoo, MI 49008-5439.
2 David Wilder is now at The University of the Pacific. 3 Brian Gaunt is now at The University of South Florida. 4 Claudia Dozier is now at The University of Florida. 5 Lisa Britton is now at Spectrum Center. * Corresponding author. Tel.:11-616-387-4925; fax:11-616-387-4550. E-mail address:jim.carr@wmich.edu (J.E. Carr).
Research in Developmental Disabilities 21 (2000) 377–391
0891-4222/00/$ – see front matter © 2000 Elsevier Science Ltd. All rights reserved. PII: S0891-4222(00)00050-0
1. Introduction
One of the most significant advances in the treatment of aberrant behavior of individuals with developmental disabilities has been the development of system- atic methods for determining behavioral function. The advent of functional assessment methods has enabled researchers and practitioners to design inter- ventions that are based on a behavior’s maintaining variable(s), rather than its topography. Function-based approaches are considered preferable to their non- function-based counterparts for several reasons. First, function-based interven- tions necessarily emphasize reinforcement-based, as opposed to punishment- based, procedures. In addition, function-based interventions are directed at the response-reinforcer relationship, thus weakening a problematic contingency as opposed to simply overpowering it. Finally, function-based interventions often involve the establishment of an adaptive response-reinforcer relationship, which may result in increased maintenance of treatment gains.
Iwata, Vollmer, Zarcone, and Rodgers (1993) described three general classes of function-based interventions. The first class, the modification of establishing opera- tions (EOs), includes antecedent manipulations designed to either weaken the rein- forcer for the aberrant behavior or strengthen that of an alternative behavior (for a review, see Wilder & Carr, 1998). The second class, extinction, involves withholding the reinforcer that maintains the aberrant behavior. Finally, in behavioral replacement procedures, the aberrant behavior’s reinforcer is provided contingent upon an alter- native behaviorand withheld for the aberrant behavior. In recent years, one of the most widely researched group of treatments for aberrant behavior has been noncon- tingent reinforcement (NCR). NCR procedures are often conceptualized as EO manipulations, although extinction sometimes plays a role in their effects. The basic premise of NCR is that an aberrant behavior’s reinforcer is delivered to the individual on a response-independent basis. Through the operation of several behavioral pro- cesses, a subsequent behavior reduction is usually observed.
Before the more substantive areas of this review are presented, a brief discussion of the termnoncontingent reinforcementis warranted. The quotes in the title of the article are a hint that the term is problematic. As has previously been discussed in the literature, NCR is a misnomer for several reasons. First, by definition, reinforcement is acontingentprocess. Second, no behavior is strength- ened as a result of NCR, compared to reinforcement procedures. Third, NCR is an imprecise description as it refers to many procedurally distinct treatments. With all of these problems with the term, one would surmise that researchers would have adopted a more precise vocabulary with which to refer to these procedures. However, this has not yet happened, and with the increasing fre- quency at which the term is being reported in the literature, we believe that a change is unlikely to occur. Therefore, throughout this review, the term NCR will be used much as it is used in the current treatment literature. We refer the reader to several published commentaries on this issue for more in-depth discussion, as well as for potential alternatives to current terminology (Carr, 1996; Poling & Normand, 1999; Vollmer, 1999).
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The purpose of this review is to briefly discuss the history of NCR and summarize the recent findings from the research literature. First, the basic research on NCR is briefly summarized, followed by a short discussion of NCR’s role as a methodological control procedure. Next, NCR is discussed as a func- tion-based treatment for aberrant behavior. We then discuss the many variables that should be considered when programming NCR schedules. Next, we discuss the behavior-change mechanisms responsible for NCR effects. Finally, sugges- tions for future research are presented.
1.1. Basic research on NCR
Although Skinner (1948) first addressed the possibilities of fixed-time (FT) schedules of reinforcement in his seminal article “Superstition in the Pigeon,” it was not until the 1960s that researchers began to systematically study NCR procedures. Since then, there have been dozens of articles published in the basic literature whose primary purposes have been to (a) examine the procedural and functional properties of NCR, and (b) use NCR as a control procedure for studying other behavioral phenomena (e.g., behavioral momentum). Since the purpose of the current paper is to review NCR procedures as they relate to clinical application, a comprehensive review of the basic NCR literature is not possible. Below, however, is a brief summary of some of the early findings from the basic literature that were important to the development of our current technology.
Zeiler (1968) evaluated variable-time (VT) and FT schedules in pigeons that had previously acquired an operant response (i.e., key pecking). The results showed that FT schedules produced consistent decreases in responding, while VT schedules produced ones that were more erratic. Rescorla and Skucy (1969) compared extinction with the response-independent delivery (i.e., VT schedules) of food in rats. The authors found that extinction (by omission) decreased responding more effectively than response-independent food delivery, although both procedures resulted in significant decreases in response rates. Lachter, Cole, and Schoenfeld (1971) evaluated both dense and lean FT schedules in pigeons and found that, although both were effective reductive procedures, the dense schedules produced the greater reductions. The aforementioned studies and others (e.g., Alleman & Zeiler, 1974; Calef et al., 1989; Dickinson & Charnock, 1985; Edwards, Peek, & Wolfe, 1970; Halliday & Boakes, 1971; Job, 1988; Oakes, Rosenblum, & Fox, 1982) illuminated a consistent phenomenon: a change from response-dependent to response-independent reinforcement consistently produces a response reduction. This finding led to NCR being adopted as an experimental control procedure as an alternative to extinction.
1.2. NCR as a control procedure
Based on findings from the basic literature, researchers introduced NCR in the applied literature as an experimental control procedure. That is, reinforcers were
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delivered independent of the target response in either FT or VT schedules to evaluate the effects of reinforcement-based procedures. Previously, extinction had been employed as the modal control procedure; however, extinction was shown to produce a possible confound. When extinction procedures are used, not only is the response-reinforcer relationship terminated, but thepresentationof the stimulus is also removed from the individual. This type of control (i.e., extinction) does not allow for the delineation of the effects of stimulus presen- tation and the response-reinforcer relationship (Lachter, 1980). In contrast, NCR procedures interrupt the response-reinforcer relationship while still presenting the stimulus to the individual, which allows for the examination of the response- reinforcer relationship independent of stimulus-presentation effects.
Numerous studies in the applied literature have since employed NCR as a control for reinforcement procedures (e.g., O’Neill & Morris, 1979; Sheppard, 1969). Below are brief descriptions of two representative studies. Hart, Reynolds, Baer, Brawley, and Harris (1968) reported one of the first demonstrations of the use of NCR as a control procedure with humans. The researchers used a reversal design to evaluate the effects of contingent adult social reinforcement on the cooperative play behavior of a 5-year-old girl. In addition to a contingent attention condition, the authors employed a noncontingent attention control procedure. Increased cooperative play was observed in the contingent attention condition, but not in the noncontingent attention condition. These results sug- gested that the contingency between the response and the reinforcer was…
