Negative side effects of noncontingent reinforcement

Descriptive characteristics of extinction bursts: A record review

Procedural extinction is sometimes associated with a temporary increase in responding known as an extinction burst. Extinction bursts present unique challenges in the context of treating behavior targeted for reduction. The present study updates the prevalence of extinction bursts using a clinical sample (N = 108) receiving treatment for targeted behavior. The prevalence of extinction bursts in our sample (24%) was consistent with that in prior literature. The extinction-burst magnitude decreased across sessions after extinction was contacted during treatment, but this sample did not demonstrate decreased persistence or magnitude of extinction bursts across successive transitions from baseline to treatment. We also examined the prevalence and magnitude of extinction bursts based on the function and topography of targeted behavior and treatment components and found no consistent relation among these variables. These findings should lead clinicians to prepare for transient extinction bursts when implementing extinction-based treatment for challenging behavior.

Basic and applied research on extinction bursts

Discontinuation of the contingency between a response and its reinforcer sometimes produces a temporary increase in the response before its rate decreases, a phenomenon called the extinction burst. Prior clinical and basic studies on the prevalence of the extinction burst provide highly disparate estimates. Existing theories on the extinction burst fail to account for the dynamic nature of this phenomenon, and the basic behavioral processes that control response bursting remain poorly understood. In this paper, we first review the basic and applied literature on the extinction burst. We then describe a recent refinement of the concatenated matching law called the temporally weighted matching law that appears to resolve the above-mentioned issues regarding the extinction burst. We present illustrative translational data based conceptually on the model. Finally, we discuss specific recommendations derived from the temporally weighted matching law regarding procedures clinicians could implement to potentially mitigate or prevent extinction bursts.

Bridging the gap between laboratory and applied research on response-independent schedules

In 1948, Skinner described the behavior of pigeons under response-independent schedules as "superstitious," and proposed that the responses were reinforced by contiguous, adventitious food deliveries. Subsequently, response-independent schedules have been of interest to both basic and applied researchers, first to understand the mechanisms involved, and later, as "noncontingent reinforcement" (NCR) to reduce undesirable behavior. However, the potential superstitious effects produced by these schedules have been challenged, with some researchers arguing that antecedent variables play a significant role. This paper examines the evidence for adventitious reinforcement from both laboratory and applied research, the results of which suggest that antecedent, nonoperant functions may be important in fully understanding the effects of NCR. We propose an applied-basic research synthesis, in which attention to potential nonoperant functions could provide a more complete understanding of response-independent schedules. We conclude with a summary of the applied implications of the nonoperant functions of NCR schedules.

Noncontingent reinforcement: Arbitrary versus maintaining reinforcers for escape-maintained problem behavior

Noncontingent reinforcement (NCR) involves the delivery of maintaining reinforcers on a time-dependent schedule and often includes extinction. However, arbitrary reinforcers may be equally efficacious during NCR without extinction for treating escape-maintained problem behavior. The purpose of this study was to extend previous research on NCR by evaluating the relative efficacy of NCR without extinction and comparing maintaining versus arbitrary reinforcers for 4 individuals with escape-maintained problem behavior. Two different NCR conditions, NCR using the maintaining reinforcer (escape) and NCR using an arbitrary reinforcer (an edible), were evaluated using multielement and reversal designs. Treatment effects varied across participants. Results for 2 participants showed a reduction in problem behavior during NCR without extinction with both the arbitrary and maintaining reinforcers. For 1 participant, results showed a reduction in problem behavior with both the arbitrary and maintaining reinforcers only when extinction was added to NCR. For the 4th participant, the maintaining reinforcer was effective during NCR without extinction, but the arbitrary reinforcer was ineffective.

The role of adventitious reinforcement during differential reinforcement of other behavior: A systematic replication

Differential reinforcement of other behavior (DRO) is commonly used to decrease problem behavior by presenting reinforcers contingent upon the absence of a target response. Although it is well demonstrated that DROs decrease response rates, the processes producing these decreases are not well understood. The present study systematically replicated previous research assessing whether adventitious reinforcement of alternative behavior contributes to the effectiveness of DRO. We presented university students with two options on a computer and reinforced target responding on a variable-ratio schedule. Next, we compared decreases in target-response rates and any increases in alternative responding during DRO schedules versus yoked variable-time schedules or extinction probes. DRO schedules resulted in the lowest target-response rate and highest alternative-response rate. These findings generally provide some support for the adventitious reinforcement of "other" behavior.

A multicomponent approach to thinning reinforcer delivery during noncontingent reinforcement schedules

We evaluated a noncontingent reinforcement procedure that involved initially providing three subjects with signaled, continuous access to the functional reinforcer for aggression and slowly increasing the amount of time subjects were exposed to the signaled unavailability of the reinforcer. Additionally, alternative potential reinforcers were available throughout the sessions. Results showed immediate and substantial reductions in aggression for all three subjects. The clinical utility of this intervention is discussed, and future research directions are recommended.

Noncontingent Reinforcement to Improve Classroom Behavior of a Student With Developmental Disability

The purpose of this study was to examine the effects of a noncontingent reinforcement intervention package implemented by an interning teacher in a special education classroom to address disruptive behavior and task engagement for a third-grade, 8-year-old boy with developmental disability. Using a within-subject reversal design (A-B-A-B), a teacher interning in Max’s classroom delivered 3-min breaks (i.e., escape) from classroom tasks on a fixed-time 2-min interval schedule for five daily sessions during the first intervention phase and for five daily sessions during the reimplementation phase; breaks were not contingent on his behavior. The intervention package also included a reinforcement menu for the student to select daily from escape activities (i.e., preferred activities including swinging and taking a walk) and a picture prompt to provide a continuous, visual reminder of the upcoming reinforcer. Results indicated increases in task engagement and decreases in disruptive behavior during phases when the intervention was applied. Implications for future research and practice are discussed.

Function-based treatments for escape-maintained problem behavior: a treatment-selection model for practicing behavior analysts

Escape from instructional activities is a common maintaining variable for problem behavior and a number of effective treatments have been developed for this function. Each of these treatments has characteristics that make them optimal for certain environments and clients, but less optimal for others. We summarize the most commonly researched function-based treatments for escape-maintained behavior, describe the contexts for which they are most appropriate, and provide a clinical model for selecting treatments based on client characteristics and the constraints of the therapeutic environment.

The role of the rat medial prefrontal cortex in adapting to changes in instrumental contingency

In order to select actions appropriate to current needs, a subject must identify relationships between actions and events. Control over the environment is determined by the degree to which action consequences can be predicted, as described by action-outcome contingencies – i.e. performing an action should affect the probability of the outcome. We evaluated in a first experiment adaptation to contingency changes in rats with neurotoxic lesions of the medial prefrontal cortex. Results indicate that this brain region is not critical to adjust instrumental responding to a negative contingency where the rats must refrain from pressing a lever, as this action prevents reward delivery. By contrast, this brain region is required to reduce responding in a non-contingent situation where the same number of rewards is freely delivered and actions do not affect the outcome any more. In a second experiment, we determined that this effect does not result from a different perception of temporal relationships between actions and outcomes since lesioned rats adapted normally to gradually increasing delays in reward delivery. These data indicate that the medial prefrontal cortex is not directly involved in evaluating the correlation between action-and reward-rates or in the perception of reward delays. The deficit in lesioned rats appears to consist of an abnormal response to the balance between contingent and non-contingent rewards. By highlighting the role of prefrontal regions in adapting to the causal status of actions, these data contribute to our understanding of the neural basis of choice tasks.

Evaluation of fixed momentary dro schedules under signaled and unsignaled arrangements

Fixed momentary schedules of differential reinforcement of other behavior (FM DRO) generally have been ineffective as treatment for problem behavior. Because most early research on FM DRO included presentation of a signal at the end of the DRO interval, it is unclear whether the limited effects of FM DRO were due to (a) the momentary response requirement of the schedule per se or (b) discrimination of the contingency made more salient by the signal. To separate these two potential influences, we compared the effects of signaled versus unsignaled FM DRO with 4 individuals with developmental disabilities whose problem behavior was maintained by social-positive reinforcement. During signaled FM DRO, the experimenter presented a visual stimulus 3 s prior to the end of the DRO interval and delivered reinforcement contingent on the absence of problem behavior at the second the interval elapsed. Unsignaled DRO was identical except that interval termination was not signaled. Results indicated that signaled FM DRO was effective in decreasing 2 subjects' problem behavior, whereas an unsignaled schedule was required for the remaining 2 subjects. These results suggest that the response requirement per se of FM DRO may not be problematic if it is not easily discriminated.

Automatic Prompting and Positive Attention to Reduce Tongue Protrusion and Head Tilting by Two Adults With Severe to Profound Intellectual Disabilities

This study assessed a simple behavioral strategy for reducing stereotypic tongue protrusion and forward head tilting displayed by a woman and a man with severe to profound intellectual disabilities. The strategy involved (a) auditory prompting (i.e., verbal encouragements to keep the tongue in the mouth or the head upright) delivered automatically at fixed intervals via a portable device, and (b) social approval delivered by a research assistant at adjustable intervals for the absence of the inappropriate behavior. The intervals arranged for the delivery of approval were extended if the inappropriate behavior occurred in concomitance with the expected delivery. Data showed that the intervention strategy was effective in reducing the stereotypic tongue protrusion and forward head tilting. Their occurrences dropped from above 40% (tongue protrusion) and close to 80% (head tilting) of the observation instances during the initial baseline to around or slightly above 10% of those instances during the second intervention period and the 3-month postintervention check.

Do children prefer contingencies? An evaluation of the efficacy of and preference for contingent versus noncontingent social reinforcement during play

Discovering whether children prefer reinforcement via a contingency or independent of their behavior is important considering the ubiquity of these programmed schedules of reinforcement. The current study evaluated the efficacy of and preference for social interaction within differential reinforcement of alternative behavior (DRA) and noncontingent reinforcement (NCR) schedules with typically developing children. Results showed that 7 of the 8 children preferred the DRA schedule; 1 child was indifferent. We also demonstrated a high degree of procedural fidelity, which suggested that preference is influenced by the presence of a contingency under which reinforcement can be obtained. These findings are discussed in terms of (a) the selection of reinforcement schedules in practice, (b) variables that influence children's preferences for contexts, and (c) the selection of experimental control procedures when evaluating the effects of reinforcement.

Applied implications of reinforcement history effects

Although the influence of reinforcement history is a theoretical focus of behavior analysis, the specific behavioral effects of reinforcement history have received relatively little attention in applied research and practice. We examined the potential effects of reinforcement history by reviewing nonhuman, human operant, and applied research and interpreted the findings in relation to possible applied significance. The focus is on reinforcement history effects in the context of reinforcement schedules commonly used either to strengthen behavior (e.g., interval schedules) or commonly used to decrease behavior (e.g., extinction).

Contingency space analysis: an alternative method for identifying contingent relations from observational data

Descriptive assessment methods have been used in applied settings to identify consequences for problem behavior, thereby aiding in the design of effective treatment programs. Consensus has not been reached, however, regarding the types of data or analytic strategies that are most useful for describing behavior-consequence relations. One promising approach involves the analysis of conditional probabilities from sequential recordings of behavior and events that follow its occurrence. In this paper we review several strategies for identifying contingent relations from conditional probabilities, and propose an alternative strategy known as a contingency space analysis (CSA). Step-by-step procedures for conducting and interpreting a CSA using sample data are presented, followed by discussion of the potential use of a CSA for conducting descriptive assessments, informing intervention design, and evaluating changes in reinforcement contingencies following treatment.

Progressing toward data intimacy: a review of within-session data analysis

Visual inspection of data is a common method for understanding, responding to, and communicating important behavior-environment relations in single-subject research. In a field that was once dominated by cumulative, moment-to-moment records of behavior, a number of graphic forms currently exist that aggregate data into larger units. In this paper, we describe the continuum of aggregation that ranges from distant to intimate displays of behavioral data. To aid in an understanding of the conditions under which a more intimate analysis is warranted (i.e., one that provides a richer analysis than that provided by condition or session aggregates), we review a sample of research articles for which within-session data depiction has enhanced the visual analysis of applied behavioral research.

Staff-administered functional analysis and treatment of aggression by an elder with dementia

In the current study, nursing home staff were taught to administer functional analyses to determine the variables maintaining aggression by an elder with dementia. The results indicated that aggression was evoked during bathroom routines and that escape maintained aggression. Staff then reduced aggression to near-zero levels with noncontingent escape. Implications for the assessment and treatment of problem behaviors in nursing home settings are discussed.

Negative automaintenance omission training is effective

Twelve pigeons were exposed to negative automaintenance contingencies for 17-27 sessions immediately after brief (14-16 sessions) or extended (168-237 sessions) exposure to positive automaintenance contingencies, or after 4-10 sessions of instrumental training. In all conditions, negative automaintenance contingencies virtually eliminated responding, reducing response rates to an average 1.3 responses per min. This reduction in response rate was validated by a model of transition between early and late response rates that assumed exponential transition of rates from one set of contingencies to the next. The model faithfully reproduced cumulative records, and yielded estimates of terminal rates under negative automaintenance that were close to operant level.

Noncontingent reinforcement, alternative reinforcement, and the matching law: a laboratory demonstration

Basic researchers, but not most applied researchers, have assumed that the behavior-decelerating effects of noncontingent reinforcement result at least partly from adventitious reinforcement of competing behaviors. The literature contains only sketchy evidence of these effects because few noncontingent reinforcement studies measure alternative behaviors. A laboratory model is presented in which concurrent schedules of contingent reinforcement were used to establish a "target" and an "alternative" behavior. Imposing noncontingent reinforcement decreased target behavior rates and increased alternative behavior rates, outcomes that were well described by the standard quantitative account of alternative reinforcement, the generalized matching law. These results suggest that adventitious reinforcement of alternative behaviors can occur during noncontingent reinforcement interventions, although the range of conditions under which this occurs remains to be determined in future studies. As an adjunct to applied studies, laboratory models permit easy measurement of alternative behaviors and parametric manipulations needed to answer many research questions.

A comparison of dense-to-lean and fixed lean schedules of alternative reinforcement and extinction

Behavior-reduction interventions typically employ dense schedules of alternative reinforcement in conjunction with operant extinction for problem behavior. After problem behavior is reduced in the initial treatment stages, schedule thinning is routinely conducted to make the intervention more practical in natural environments. In the current investigation, two methods for thinning alternative reinforcement schedules were compared for 3 clients who exhibited severe problem behavior. In the dense-to-lean (DTL) condition, reinforcement was delivered on relatively dense schedules (using noncontingent reinforcement for 1 participant and functional communication training for 2 participants), followed by systematic schedule thinning to progressively leaner schedules. During the fixed lean (FL) condition, reinforcement was delivered on lean schedules (equivalent to the terminal schedule of the DTL condition). The FL condition produced a quicker attainment of individual treatment goals for 2 of the 3 participants. The results are discussed in terms of the potential utility of using relatively lean schedules at treatment outset.

Effects of alternative reinforcement on human behavior: the source does matter

Competing theories regarding the effects of delivering periodic response-independent reinforcement (more accurately, response-independent points exchanged for money) on a baseline rate of behavior were evaluated in human subjects. Contiguity theory holds that these events decrease target responding because incompatible behavior is adventitiously strengthened when the point deliveries follow target behavior closely in time. Matching theory holds that response-independent points, like any other alternative reinforcer, should reduce target responding. On this view, temporal contiguity between target responding and response-independent point delivery is unimportant. In our experiment, four different responses (moving a joystick in four different directions) were reinforced with points exchangeable for money according to four independent variable-interval schedules. Different schedules of point delivery were then superimposed on these baselines. When all superimposed point deliveries occurred immediately after one of the four responses (the target response), time allocated to target responding increased. When the superimposed point deliveries could be delivered at any time, time allocated to target responding declined and other behavior increased. When superimposed points could never immediately follow target responses, time allocated to target responding decreased further and other behavior or pausing predominated. The findings underscore the contribution of temporal contiguity in the effects of response-independent deliveries of food, money, points, etc.

Functional analysis of problem behavior: a review

Functional analysis methodology focuses on the identification of variables that influence the occurrence of problem behavior and has become a hallmark of contemporary approaches to behavioral assessment. In light of the widespread use of pretreatment functional analyses in articles published in this and other journals, we reviewed the literature in an attempt to identify best practices and directions for future research. Studies included in the present review were those in which (a) a pretreatment assessment based on (b) direct observation and measurement of (c) problem behavior was conducted under (d) at least two conditions involving manipulation of an environmental variable in an attempt (e) to demonstrate a relation between the environmental event and behavior. Studies that met the criteria for inclusion were quantified and critically evaluated along a number of dimensions related to subject and setting characteristics, parametric and qualitative characteristics of the methodology, types of assessment conditions, experimental designs, topographies of problem behaviors, and the manner in which data were displayed and analyzed.

Operant variability: evidence, functions, and theory

Although responses are sometimes easy to predict, at other times responding seems highly variable, unpredictable, or even random. The inability to predict is generally attributed to ignorance of controlling variables, but this article is a review of research showing that the highest levels of behavioral variability may result from identifiable reinforcers contingent on such variability. That is, variability is an operant. Discriminative stimuli and reinforcers control it, resulting in low or high variability, depending on the contingencies. Schedule-of-reinforcement effects are orderly, and choosing to vary or repeat is lawfully governed by relative reinforcement frequencies. The operant nature of variability has important implications. For example, learning, exploring, creating, and problem solving may partly depend on it. Abnormal levels of variability, including those found in psychopathologies such as autism, depression, and attention deficit hyperactivity disorder, may be modified through reinforcement. Operant variability may also help to explain some of the unique attributes of voluntary action.

Pharmacological manipulations of the extinction process of fear-induced ultrasonic vocalization in rats

The effects of pharmacological manipulation on the extinction process of fear-induced ultrasonic vocalizations (USVs), which are considered distress calls related to anxiety, were investigated. Male Wistar rats were conditioned to emit USVs by being given repeated electrical foot-shocks while in a chamber. After 10 sessions of conditioning, the animals started to emit USVs upon mere exposure to the shock chamber without being shocked. Using these animals, the extinction process of the USVs was examined. With repeated exposure to the chamber without shocks, the USVs first increased and then gradually decreased. i.e., the extinction burst was observed. Daily intraperitoneal injections of a benzodiazepine-GABA receptor agonist diazepam (DZP; 1.0 mg/kg) or a tricyclic antidepressant clomipramine (CLM; 20 mg/kg) inhibited this extinction burst. Moreover, CLM, but not DZP, shortened the period required for extinction as compared with the vehicle-treated animals. Following the extinction phase, the emission of USVs was enhanced by the cessation of both drug treatments. These results suggest that CLM would be useful for reducing anxiety-related behaviors in the extinction process, as long as withdrawal symptoms after long-term drug treatments are taken into consideration.

An experimental analysis of aggression

Iwata, Dorsey, Slifer, Bauman, and Richman developed an assessment method to identify the operant functions of self-injurious behavior. In this study, a similar method was used to assess the operant functions of aggression displayed by children and adolescents with developmental disabilities. Although previous research has shown that aggression is an operant behavior, there has been no comprehensive analysis of aggression using analog functional analysis method. Eight children and adolescents participated. The experimental conditions involved attention, escape, materials, no interaction, and control. Results for 7 of the 8 participants identified clear operant functions (positive or negative reinforcement) for aggression. For 1 child, subsequent analyses suggested that aggression was possibly sensitive to peer attention as reinforcement.

Fixed-time schedule effects as a function of baseline reinforcement rate

Using an arbitrary response, we evaluated fixed-time (FT) schedules that were either similar or dissimilar to a baseline (response-dependent) reinforcement schedule and extinction. Results suggested that both FT schedules and extinction resulted in decreased responding. However, FT schedules were more effective in reducing response rates if the FT reinforcer rate was dissimilar to baseline reinforcer rates. Possible reasons for this difference were evaluated with data analysis methods designed to identify adventitious response-reinforcer relations.

Reinforcement contingencies and social reinforcement: some reciprocal relations between basic and applied research

Reinforcement contingencies and social reinforcement are ubiquitous phenomena in applied behavior analysis. This discussion paper is divided into two sections. In the first section, reinforcement contingencies are discussed in terms of the necessary and sufficient conditions for reinforcement effects. Response-stimulus dependencies, conditional probabilities, and contiguity are discussed as possible mechanisms of, and arrangements for, reinforcement effects. In the second section, social reinforcement is discussed in terms of its functional subtypes and reinforcement context effects. Two underlying themes run throughout the discussion: (a) Applied research would benefit from a greater understanding of existing basic research, and (b) basic research could be designed to specifically address some of the issues about reinforcement that are central to effective application.

A method for analyzing changes in response efficiency

Although experimental effects typically are evaluated by summarizing levels of responding across time (e.g., calculating the mean levels of problem behavior during 10-min sessions), these data summaries may obscure important mechanisms that may be responsible for changes in responding. A case study is reported to illustrate alternative methods of data analysis when decreasing trends in responding may be due to increases in response efficiency.

A variation of noncontingent reinforcement in the treatment of aberrant behavior

We examined the effectiveness of a variation of noncontingent reinforcement (NCR) that incorporated a stimulus-delay procedure in the reduction of aberrant behavior maintained by positive reinforcement. Functional analyses for three individuals diagnosed with developmental disabilities indicated that their behaviors were maintained by positive reinforcement: one in the form of access to a tangible item, another by attention, and the third by physical contact. We implemented NCR with the delay procedure with two participants using reversal designs to evaluate effects. We also compared this NCR variation and DRO with the third participant to evaluate reinforcer-delivery rates. The variation of NCR was successful in reducing all aberrant behavior to near-zero levels. A comparison of reinforcer delivery between NCR with the stimulus-delay procedure and DRO demonstrated that the participant accessed more reinforcement with NCR. Results are discussed in the context of enhancing decelerative interventions with emphases on minimizing response effort for caregivers and maximizing access to reinforcement for the individuals.

A review of "noncontingent" reinforcement as treatment for the aberrant behavior of individuals with developmental disabilities

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 (t) directions for future research.

Reinforcing variability in adolescents with autism

Five adolescents with autism, 5 adult control participants, and 4 child controls received rewards for varying their sequences of responses while playing a computer game. In preceding and following phases, rewards were provided at approximately the same rate but were independent of variability. The most important finding was that, when reinforced, variability increased significantly in all groups. Reinforced variability could provide the necessary behavioral substrate for individuals with autism to learn new responses.

Effects of noncontingent reinforcement on problem behavior and stimulus engagement: the role of satiation, extinction, and alternative reinforcement

This study examined the effects of noncontingent reinforcement (NCR) with and without extinction on problem behavior and stimulus engagement (consumption of reinforcement) of 4 participants. Reductions in problem behavior using NCR have frequently been attributed to both satiation of the reinforcer and extinction. In the current study, aspects of the NCR treatment effects were difficult to explain based solely on either a satiation or an extinction account. Specifically, it was found that stimulus engagement remained high throughout the NCR treatment analysis, and that problem behavior was reduced to near-zero levels during NCR without extinction. The implications of these findings are discussed with respect to the satiation and extinction hypotheses frequently described in the applied literature. Findings from basic studies examining the effects of response-independent schedules are presented, and are used as the basis for a matching theory account of NCR-related effects. It is proposed that reductions in problem behavior observed during NCR interventions may be a function of the availability of alternative sources of reinforcement.

Variable-time reinforcement schedules in the treatment of socially maintained problem behavior

Noncontingent reinforcement (NCR) consists of delivering a reinforcer on a time-based schedule, independent of responding. Studies evaluating the effectiveness of NCR as treatment for problem behavior have used fixed-time (FT) schedules of reinforcement. In this study, the efficacy of NCR with variable-time (VT) schedules was evaluated by comparing the effects of VT and FT reinforcement schedules with 2 individuals who engaged in problem behavior maintained by positive reinforcement. Both FT and VT schedules were effective in reducing problem behavior. These findings suggest that VT schedules can be used to treat problem behavior maintained by social consequences.

Competition between noncontingent and contingent reinforcement schedules during response acquisition

We examined the extent to which noncontingent reinforcement (NCR), when used as treatment to reduce problem behavior, might interfere with differential reinforcement contingencies designed to strengthen alternative behavior. After conducting a functional analysis to identify the reinforcers maintaining 2 participants' self-injurious behavior (SIB), we delivered those reinforcers under dense NCR schedules. We delivered the same reinforcers concurrently under differential-reinforcement-of-alternative-behavior (DRA) contingencies in an attempt to strengthen replacement behaviors (mands). Results showed that the NCR plus DRA intervention was associated with a decrease in SIB but little or no increase in appropriate mands. In a subsequent phase, when the NCR schedule was thinned while the DRA schedule remained unchanged, SIB remained low and mands increased. These results suggest that dense NCR schedules may alter establishing operations that result in not only suppression of problem behavior but also interference with the acquisition of appropriate behavior. Thus, the strengthening of socially appropriate behaviors as replacements for problem behavior during NCR interventions might best be achieved if the NCR schedule is first thinned.

Noncontingent reinforcement: effects of satiation versus choice responding

Recent research findings suggest that the initial reductive effects of noncontingent reinforcement (NCR) schedules on destructive behavior result from the establishing effects of an antecedent stimulus (i.e., the availability of "free" reinforcement) rather than extinction. A number of authors have suggested that these antecedent effects result primarily from reinforcer satiation, but an alternative hypothesis is that the individual attempts to access contingent reinforcement primarily when noncontingent reinforcement is unavailable, but chooses not to access contingent reinforcement when noncontingent reinforcement is available. If the satiation hypothesis is more accurate, then the reductive effects of NCR should increase over the course of a session, especially for denser schedules of NCR, and should occur during both NCR delivery and the NCR inter-reinforcement interval (NCR IRI). If the choice hypothesis is more accurate, then the reductive effects of NCR should be relatively constant over the course of a session for both denser and leaner schedules of NCR and should occur almost exclusively during the NCR interval (rather than the NCR IRI). To evaluate these hypotheses, we examined within-session trends of destructive behavior with denser and leaner schedules of NCR (without extinction), and also measured responding in the NCR interval separate from responding in the NCR IRI. Reductions in destructive behavior were mostly due to the participants choosing not to access contingent reinforcement when NCR was being delivered and only minimally due to reinforcer satiation.

Further evaluation of reinforcer magnitude effects in noncontingent schedules

We closely replicated the procedures of a previous study that showed a positive relationship between reinforcer magnitude and the response-rate-reducing effects of noncontingent schedules (NCS). NCS reduced response rates, as expected, but the NCS-magnitude effect was not reproduced, illuminating possible weaknesses of current arbitrary-response procedures and suggesting avenues for future research.

On the establishing and reinforcing effects of termination of demands for destructive behavior maintained by positive and negative reinforcement

The results of functional analyses suggested that the destructive behavior of two individuals was sensitive to escape and attention as reinforcement. In an instructional context, we evaluated the effects of reinforcing compliance with functional reinforcers when destructive behavior produced a break. For one participant we also evaluated the effects of reinforcing compliance with functional reinforcers when destructive behavior produced no differential consequence (escape extinction). We hypothesized that destructive behavior failed to decrease in an instructional context when compliance resulted in a break because presentation of a break evoked attention-maintained destructive behavior. The results of a reinforcer assessment supported this hypothesis by demonstrating that demands functioned as positive reinforcement when no alternative activities were available. These results are discussed in terms of the importance of establishing operations in determining the appetitive or aversive properties of stimuli when destructive behavior is multiply controlled.

Fixed-time schedules attenuate extinction-induced phenomena in the treatment of severe aberrant behavior

We compared the effects of extinction (EXT) and fixed-time (FT) schedules as treatment for severe problem behavior displayed by 3 individuals with developmental disabilities. First, functional analyses identified the reinforcers maintaining aberrant behavior for all 3 individuals. Next, EXT and FT schedules were compared using a multielement design. During EXT, the reinforcer maintaining problem behavior was withheld. During FT, the reinforcers were presented response independently at preset intervals. Results showed that FT schedules were generally more effective than EXT schedules in reducing aberrant behavior. FT schedules may be used in situations when extinction-induced phenomena are problematic.

On the effects of noncontingent delivery of differing magnitudes of reinforcement

We conducted a parametric analysis of response suppression associated with different magnitudes of noncontingent reinforcement (NCR). Participants were 5 adults with severe or profound mental retardation who engaged in a manual response that was reinforced on variable-ratio schedules during baseline. Participants were then exposed to NCR via multielement and reversal designs. The fixed-time schedules were kept constant while the magnitude of the reinforcing stimulus was varied across three levels (low, medium, and high). Results showed that high-magnitude NCR schedules produced large and consistent reductions in response rates, medium-magnitude schedules produced less consistent and smaller reductions, and low-magnitude schedules produced little or no effect on responding. These results suggest that (a) NCR affects responding by altering an establishing operation (i.e., attenuating a deprivation state) rather than through extinction, and (b) magnitude of reinforcement is an important variable in determining the effectiveness of NCR.

Evaluation of client preference for function-based treatment packages

Functional communication training (FCT) and noncontingent reinforcement (NCR) are commonly prescribed treatments that are based on the results of a functional analysis. Both treatments involve delivery of the reinforcer that is responsible for the maintenance of destructive behavior. One major difference between the two treatment procedures is that client responding determines reinforcement delivery with FCT (e.g., reinforcement of communication is delivered on a fixed-ratio 1 schedule) but not with NCR (e.g., reinforcement is delivered on a fixed-time 30-s schedule). In the current investigation, FCT and NCR were equally effective in reducing 2 participants' destructive behavior that was sensitive to attention as reinforcement. After the treatment analysis, the participants' relative preference for each treatment was evaluated using a modified concurrent-chains procedure. Both participants demonstrated a preference for the FCT procedure. The results are discussed in terms of treatment efficacy and preference for control over when reinforcement is delivered. In addition, a method is demonstrated in which clients with developmental disabilities can participate in selecting treatments that are designed to reduce their destructive behavior.

Noncontingent delivery of arbitrary reinforcers as treatment for self-injurious behavior

Results of recent research have shown that noncontingent reinforcement (NCR) can be effective in reducing the frequency of behavior problems. In typical NCR applications, the reinforcer that is responsible for behavioral maintenance (as demonstrated through a functional analysis) no longer follows occurrences of the target behavior but instead is delivered according to a time-based schedule. Thus, it is unclear if NCR would be effective if the target behavior continued to be reinforced or if arbitrary reinforcers (i.e., those irrelevant to behavioral maintenance) were substituted for the maintaining reinforcers in the NCR procedure. In this study, 2 individuals whose self-injurious behavior (SIB) was maintained by positive reinforcement were exposed to conditions in which arbitrary and maintaining reinforcers were withheld and were delivered either contingently or noncontingently. Results indicated that noncontingent delivery of arbitrary reinforcers was effective in reducing SIB even though occurrences of SIB produced access to the maintaining reinforcer. These results suggest that (a) arbitrary reinforcers may sometimes be substituted for maintaining reinforcers, (b) an important component of NCR procedures is alteration of a behavior's establishing operation, and (c) NCR with arbitrary reinforcers might therefore be effective when maintaining reinforcers cannot be identified or withheld during the course of treatment.