Combining noncontingent reinforcement and differential reinforcement schedules as treatment for aberrant behavior

Reinforcer value moderates response magnitude and persistence during extinction: A randomized trial

Extinction bursts, or temporary increases in rates and intensities of behavior during extinction, can preclude the inclusion of extinction in intervention packages meant to suppress severe challenging behavior. To identify underlying behavioral mechanisms responsible for response persistence and bursting, 69 adults with developmental disabilities completed a low-stakes translational investigation employing a 2 × 2 factorial, crossed, and randomized matched blocks design, with batched randomization logic. In each of the four test groups, we made distinct antecedent manipulations with two value parameters commonly studied through behavioral economics (i.e., demand intensity, Pmax) and evaluated the extent to which each of these manipulations influenced target responding during extinction. Although we found statistically significant differences attributable to both parameters, variations in reinforcer consumption relative to demand intensity were most influential across all dependent variables. This outcome implicates consumption relative to demand intensity as both a mitigating and exacerbating preextinction factor that influences the prevalence of adverse collateral extinction effects (e.g., bursts).

A laboratory model of canine search vigilance decrement, II: Noncontingent reward and Pavlovian appetitive stimuli

Detection dogs have demonstrated reduced performance in operational settings when required to search in an environment where few to no target odors are present. This study's purpose was to increase detection dog accuracy using noncontingent reward (NCR) and Pavlovian stimuli associated with reward. Eighteen dogs were randomly spilt into two groups and received four 40-trial sessions in an operational and training context at 90% odor prevalence (baseline). Following baseline, in the operational context (now at 10% odor prevalence), experimental dogs received an NCR schedule consisting of delivering food rewards at the end of 66% of trials. After the NCR Test, dogs returned to baseline. During baseline, the experimental dogs received 10 days of delayed Pavlovian conditioning to a tone. During the test phase, the conditioned stimulus (tone) was presented to experimental dogs on average every two trials for 30 s in the operational context (now at 10% odor prevalence). Overall, NCR showed a nonsignificant trend for increased responding in the experimental group but tended to increase false alerts; therefore, a permutation of an NCR-like reward schedule may maintain search. The Pavlovian conditioned stimulus didn't decrease timeouts or improve accuracy, but a within-session analysis indicated that the dogs were more likely to time out and less likely to false alert when the tone was on than when it was off.

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.

Behavioral Assessment and Treatment of Aerophagia

Aerophagia is characterized by excessive air swallowing and can have serious negative effects on one’s health. We present the assessment and treatment of a 16-year-old girl, Khloe, with developmental disabilities and aerophagia. The initial assessment indicated that aerophagia occurred primarily to access attention in a divided attention context; however, our function-based treatment did not result in a clinically significant reduction in problem behavior. We then conducted a second assessment that indicated that Khloe’s aerophagia indeed occurred primarily in a divided attention context, but that it persisted independent of social consequences. We concluded that the divided attention context served as a motivating variable for aerophagia. Our second treatment consisted of differential reinforcement of other behavior, noncontingent access to competing stimuli, and graduated exposure to contextual variables (i.e., people and divided attention) that occasioned aerophagia. The treatment was successful in reducing rates of aerophagia. We discuss implications for assessment and treatment, as well as recommendations for clinicians and students.

A Meta-Analysis of Single-Case Research on Applied Behavior Analytic Interventions for People With Down Syndrome

This systematic review evaluates single-case research design studies investigating applied behavior analytic (ABA) interventions for people with Down syndrome (DS). One hundred twenty-five studies examining the efficacy of ABA interventions on increasing skills and/or decreasing challenging behaviors met inclusion criteria. The What Works Clearinghouse standards and Risk of Bias in N-of-1 Trials scale were used to analyze methodological characteristics, and Tau-U effect sizes were calculated. Results suggest the use of ABA-based interventions are promising for behavior change in people with DS. Thirty-six high-quality studies were identified and demonstrated a medium overall effect. A range of outcomes was targeted, primarily involving communication and challenging behavior. These outcomes will guide future research on ABA interventions and DS.

A comparison of single-case evaluation tools applied to functional communication training with augmentative and alternative communication supports for students with developmental disabilities

BACKGROUND

Students with developmental disabilities frequently present with both limited vocal speech and challenging behavior. Functional communication training (FCT) with augmentative and alternative communication (AAC) supports, is a commonly recommended intervention to reduce challenging behavior for these students, while also increasing appropriate communication.

AIMS

Current research on this topic has not applied multiple evaluation tools, despite the recent suggestion to do so. Further, there are limited studies in the field of special education that have (a) applied multiple evaluation tools and (b) compared the results of the tools.

METHOD

In the current review, we applied three evaluation tools to intervention studies examining the use of FCT with AAC supports in school-based settings to determine the current level of scientific support for this intervention. We identified 38 studies, which contained 59 single-case designs (SCDs). Next, we compared the methodological rigor and/or quality, outcome scores, and Evidence-Based Practice (EBP) ratings provided by the three evaluation tools.

RESULTS AND CONCLUSION

Our results yielded inconsistent methodological rigor and/or quality, participant outcome measures, and EBP classifications between the evaluation tools. No two evaluation tools completely aligned. Limitations and future research are discussed.

Does teaching an omnibus mand preclude the development of specifying mands?

When problem behavior is controlled by a synthesized reinforcement contingency, a simple omnibus mand that yields access to all reinforcers simultaneously has been shown to effectively replace problem behavior. The question arises as to whether teaching an omnibus mand will preclude the acquisition of specifying mands for each of the combined reinforcers. In this study, after 3 students diagnosed with autism acquired an omnibus mand ("My way, please") that yielded all identified reinforcers simultaneously, specifying mands (e.g., "All done," "May I have my toys?" "Play with me") were taught to yield each individual reinforcer (e.g., escape, tangibles, attention). Problem behavior was immediately eliminated for all children, and the omnibus mand was acquired quickly. Teaching an omnibus mand did not preclude acquisition of specifying mands for any learner and instead allowed for the acquisition of specifying mands once problem behavior had been effectively reduced.

Treatment Burst Data Points and Single Case Design Studies: A Bayesian N-of-1 Analysis for Estimating Treatment Effect Size

Single-case experimental designs (SCED) evaluate treatment effects for each participant, but it is difficult to aggregate and quantify treatment effects across SCED participants receiving the same type of treatment. We applied Bayesian analytic procedures to SCED data aggregated across participants that have previously only been applied to large-N and group design studies of treatment effect sizes. For the current study, we defined transient elevated treatment data points as (1) above the range of the last five baseline sessions during the first three sessions of treatment (i.e., extinction burst); (2) within or above the range of baseline after the first three treatment sessions (i.e., recurrence burst); or (3) thinning phase data points above the last three prethinning treatment data points (i.e., thinning burst). Results indicated that the treatment effect sizes remained large regardless of controlling for transient elevated treatment data points. Finally, we examined the effects of reinforcer schedule thinning on estimates of treatment effect size. Results indicated a moderate negative impact of schedule thinning on treatment effect size with a 16% decrease in effect size. Recommendations for research and practice are provided, and the utility of using Bayesian analysis in single-case experimental designs is discussed.

Applying Standards of Effectiveness to Noncontingent Reinforcement: A Systematic Literature Review

Noncontingent reinforcement is a time-based schedule of reinforcement that has been shown to decrease problem behavior. Although the intervention is considered well established, there exist concerns that much of the supporting research has been conducted under highly controlled experimental conditions that may lack ecological validity. That is, although the efficacy has been demonstrated, the effectiveness in less controlled settings has not. To evaluate this concern, we analyzed research on noncontingent reinforcement between 1993 and 2017. Standards of evidence for effectiveness were adapted from prevention science and applied to noncontingent reinforcement literature. We specifically focused on generalizability across populations and settings, the conditions under which the intervention was applied, specific treatment parameters, opportunity cost, and social validity. Our results indicate several areas where evidence of noncontingent reinforcement effectiveness in applied settings is limited. We identify these limitations and provide a range of recommendations for future research to promote more widespread dissemination of the procedure.

Differential Reinforcement of Other Behaviors to Treat Challenging Behaviors Among Children With Autism: A Systematic and Quality Review

This review summarizes the literature regarding differential reinforcement of other behaviors (DRO) to treat challenging behavior among children with autism spectrum disorder (ASD) and determines the quality of studies among the current literature according to the 2014 Council for Exceptional Children (CEC): Standards for Evidence-Based Practices in Special Education. Studies that focused on the use of DRO in the treatment of challenging behavior for individuals with ASD were included for systematic analysis. Forty-five studies were identified for inclusion in this review and were evaluated using the eight quality indicators described by the CEC. To the authors’ knowledge, this is the only systematic review of the literature that evaluates DRO as an intervention for individuals diagnosed with ASD. Principle findings, practical recommendations, and areas of future research are discussed.

Systematic Review of Differential Reinforcement of Alternative Behavior Without Extinction for Individuals With Autism

The purpose of this article is to review the literature on differential reinforcement of alternative behavior procedures without extinction for individuals with autism. Using predetermined inclusion criteria, a total of 10 studies were included and summarized in terms of the following: (a) participant characteristics (e.g., sex, age, and diagnosis), (b) treatment setting, (c) problem behavior, (d) function, (e) alternative behavior, (f) intervention, (g) outcomes, and (h) conclusiveness of evidence. Of the 10 studies, nine demonstrated positive effects and one mixed effects. Five studies successfully reduced problem behavior by manipulating different reinforcement parameters (magnitude, immediacy, and quality) and four manipulated the schedule of reinforcement. One study had mixed results with two of the three participants requiring extinction. The findings of this review suggest that variations of differential reinforcement of alternative behavior interventions without an extinction component may be considered promising practices for the treatment of challenging behavior in individuals with autism.

Correspondence between the results of functional analyses and brief functional analyses

PURPOSE

This study sought to examine the correspondence between brief functional analyses and more thorough functional analyses as described in the model of functional assessment proposed by Vollmer et al.¹ Methods: A panel of trained clinicians indicated the presence/absence of specific functions of problem behavior based on graphic results from brief functional analyses and functional analyses conducted with 19 participants. These conclusions were compared across assessments.

RESULTS

The functions identified by the panel based on results of brief functional analyses had low correspondence with those of the more thorough functional analysis conducted with the same participants.

CONCLUSIONS

Although brief-functional analyses appear regularly in clinical practice and the literature, findings from this study suggest that results may differ from those of more thorough functional analyses. Additional study is necessary to determine the cause of discrepant results between these two methodologies.

Noncontingent reinforcement without extinction plus differential reinforcement of alternative behavior during treatment of problem behavior

The effects of noncontingent reinforcement (NCR) without extinction during treatment of problem behavior maintained by social positive reinforcement were evaluated for five individuals diagnosed with autism spectrum disorder. A continuous NCR schedule was gradually thinned to a fixed-time 5-min schedule. If problem behavior increased during NCR schedule thinning, a continuous NCR schedule was reinstated and NCR schedule thinning was repeated with differential reinforcement of alternative behavior (DRA) included. Results showed an immediate decrease in all participants' problem behavior during continuous NCR, and problem behavior maintained at low levels during NCR schedule thinning for three participants. Problem behavior increased and maintained at higher rates during NCR schedule thinning for two other participants; however, the addition of DRA to the intervention resulted in decreased problem behavior and increased mands.

Noncontingent reinforcement of disruptive behaviors in personal care home settings

The purpose of this case study was to examine the potential of using noncontingent reinforcement (NCR) to reduce the frequency of disruptive behaviors of three elderly persons in personal care home (PCH) settings. Assessment indicated that participants were engaging in the disruptive behaviors to obtain social attention from PCH staff. Social attention, up to 1 min of staff making eye contact with the participant and directing positive verbal statements toward the participant, was given on a fixed time interval (from morning through early evening) beginning every 20 min and fading to every 30 min. Results indicate that NCR reduced the frequency of the disruptive behaviors.

The effects of fixed-time reinforcement schedules on functional response classes: a translational study

Research on functional response classes has applied significance because less severe forms of problem behavior have been found to co-occur with more severe forms. In addition, the most severe forms of problem behavior are sometimes targeted for intervention without monitoring other less severe forms. In such cases, it is unknown whether and how untreated forms of problem behavior covary with the targeted behaviors. The present study employed a translational procedure (with button presses as the target behavior) to investigate response covariation under noncontingent reinforcement with typically developing preschoolers. The results indicated that noncontingent reinforcement was generally effective in decreasing all response class members when only one member was targeted.

Extended Analysis of Empirical Citations with Skinner's Verbal Behavior: 1984-2004

The present paper comments on and extends the citation analysis of verbal operant publications based on Skinner's Verbal Behavior (1957) by Dymond, O'Hora, Whelan, and O'Donovan (2006). Variations in population parameters were evaluated for only those studies that Dymond et al. categorized as empirical. Preliminary results indicate that the majority of empirical research in the area of verbal behavior has been conducted with the younger developmentally disabled population and has focused on verbal operants from the introductory chapters of Skinner's book. It is clear that Verbal Behavior has influenced empirical research over the past 50 years. We believe, however, that there are many underdeveloped research areas originating from Verbal Behavior that have not yet been addressed. Suggestions for extended areas of research are provided.

The effects of variable-time delivery of food items and praise on problem behavior reinforced by escape

Prior research indicates that reinforcement of an appropriate response (e.g., compliance) can produce concomitant reductions in problem behavior reinforced by escape when problem behavior continues to produce negative reinforcement (e.g., Lalli et al., 1999). These effects may be due to a preference for positive over negative reinforcement or to positive reinforcement acting as an abolishing operation, rendering demands less aversive and escape from demands less effective as negative reinforcement. In the current investigation, we delivered a preferred food item and praise on a variable-time 15-s schedule while providing escape for problem behavior on a fixed-ratio 1 schedule in a demand condition for 3 participants with problem behavior maintained by negative reinforcement. Results for all 3 participants showed that variable-time delivery of preferred edible items reduced problem behavior even though escape continued to be available for these responses. These findings are discussed in the context of motivating operations.

Use of differential reinforcement to reduce behavior problems in adults with intellectual disabilities: a methodological review

The least-restrictive-alternative guideline for providing treatment emphasizes the use of non-aversive procedures to reduce maladaptive behaviors in individuals with intellectual disability (ID). Differential reinforcement (DR) is an excellent example of such a non-aversive, reinforcement based behavioral intervention. The purpose of this literature review was to summarize and provide a methodological analysis of studies, conducted between 1980 and 2009, using a DR contingency to reduce problem behaviors in adults with ID. A total of 31 studies were located that met the inclusion criteria. Of these, 15 reported DR to be an effective intervention when used independently. Of the remaining, 10 studies found DR to be useful as part of a treatment package, and six found a DR contingency used independently to be ineffective, and only observed treatment effects when an aversive component was added. Very few studies assessed the use of DR in older adults and in individuals with mild ID; these reflect areas of future research. A methodological analysis found that several studies did not report information on key methodological variables; for example, conducting a functional analysis and a stimulus preference assessment to guide choice of treatment and reinforcers, thinning very dense DR schedules, assessing collateral behaviors, generalization of behavior change across settings and implementers, and following up treatment outcomes over time. The overall positive findings about the effectiveness of DR are encouraging; however, more methodologically robust studies would serve to make such findings more conclusive and practically relevant for implementation in natural settings for adults with ID.

Response persistence: the effects of stimulus control on negatively reinforced problem behavior in a concurrent operant

In the context of instructional demands, compliance and problem behavior can be considered concurrent operants. Of applied interest is increasing one response (i.e., compliance) while decreasing the other (i.e., problem behavior). Strategic arrangement of reinforcement can alter response allocation accordingly. Such schedules can also influence response persistence and generalization. A case study is used to illustrate the effects of stimulus-reinforcer relations in a concurrent-operants arrangement involving an adult with developmental disabilities and problem behavior. Results are discussed in the context of basic operant research findings in the areas of stimulus control and behavioral persistence.

A review of empirical support for differential reinforcement of alternative behavior

Differential reinforcement of alternative behavior (DRA) is one of the most common behavior analytic interventions used to decrease unwanted behavior. We reviewed the DRA literature from the past 30 years to identify the aspects that are thoroughly researched and those that would benefit from further emphasis. We found and coded 116 empirical studies that used DRA, later grouping them into categories that met APA Division 12 Task Force criteria. We found that DRA has been successful at reducing behaviors on a continuum from relatively minor problems like prelinguistic communication to life-threatening failure to thrive. DRA with and without extinction is well established for treating destructive behavior of those with developmental disabilities, and to combat food refusal.

General outcome measures for verbal operants

A general outcome measure (GOM) can be used to show progress towards a long-term goal. GOMs should sample domains of behavior across ages, be sensitive to change over time, be inexpensive and easy to use, and facilitate decision making. Skinner's (1957) analysis of verbal behavior may benefit from the development of GOM. To develop GOM, we conducted a review of the literature on mands, tacts, echoics, and intraverbals. The four areas reviewed included (a) an examination of the participant's response form (i.e., vocal or nonvocal), (b) the type of prompt used, (c) types of materials used, and (d) timing of responses or sessions. Based on the review of the literature, we developed GOM for mands and tacts. This paper attempts to bridge the concept of GOMs with Skinner's analysis of verbal behavior.

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).

Incorporating "motivation" into the functional analysis of challenging behavior: on the interactive and integrative potential of the motivating operation

Sensitivity theory attempts to account for the variability often observed in challenging behavior by recourse to the "aberrant motivation" of people with intellectual and developmental disabilities. In this article, we suggest that a functional analysis based on environmental (challenging environments) and biological (challenging needs) motivating operations provides a more parsimonious and empirically grounded account of challenging behavior than that proposed by sensitivity theory. It is argued that the concept of the motivating operation provides a means of integrating diverse strands of research without the undue inference of mentalistic constructs. An integrated model of challenging behavior is proposed, one that remains compatible with the central tenets of functional analysis.

Experimental analysis and treatment of multiply controlled problem behavior: a systematic replication and extension

We evaluated interventions designed to reduce multiply controlled problem behavior exhibited by a young boy with developmental disabilities, using a multiple baseline design. Each intervention was designed to address a specific social function of problem behavior. Results showed that the separate interventions were useful in reducing problem behavior, and terminal schedules were reached by way of schedule thinning (attention condition) and delays to reinforcement (tangible and escape conditions).

The efficacy of noncontingent escape for decreasing children's disruptive behavior during restorative dental treatment

We evaluated the effectiveness of a dentist-implemented behavioral intervention in which brief escape from dental treatment was provided on a regular basis, independent of the child's behavior. Within a multiple baseline design across subjects, 5 children, ages 4 to 7 years, were provided with temporary escape from dental treatment on a fixed-time schedule. The intervals were signaled by an electronic timer worn by the dentist. Clinically significant reductions were observed in physically disruptive behavior across all 5 children with the introduction of noncontingent escape, and verbally disruptive behavior was markedly reduced in 4 of the 5 children. In addition, the dental staff s use of physical restraint was reduced to near zero across all 5 children. The research extends the literature in both clinical dentistry and in applied behavior analysis by demonstrating that a dentist can easily and effectively implement noncontingent reinforcement to produce clinically significant and socially important changes in children's health behavior.

Citation Analysis of Skinner's Verbal Behavior: 1984-2004

The present study undertook an updated citation analysis of Skinner's (1957)Verbal Behavior. All articles that cited Verbal Behavior between 1984 and 2004 were recorded and content analyzed into one of five categories; four empirical and one nonempirical. Of the empirical categories, studies that employed a verbal operant from Skinner's analysis were assigned to either basic, applied, or observational categories. Empirical studies that did not employ a verbal operant were categorized as other-empirical. The total number of citations remained stable across the review period and averaged just over 52 per year. Of these, 80% were from nonempirical articles, 13.7% were from other-empirical articles, 4% were from applied articles, 1.4% were from basic articles, and 0.9% were from observational articles. An "obliteration" analysis was also conducted to identify articles that employed Skinner's verbal operant terms but did not cite Verbal Behavior. This analysis identified 44 additional articles, suggesting that a degree of obliteration had occurred in the half century since the publication of Verbal Behavior. In particular, the analysis suggests that the verbal operant of manding has sufficient presence in the applied empirical literature to render citation of Verbal Behavior redundant. Overall, Verbal Behavior continues to make an important contribution to the psychological literature.

The effects of fixed-time and contingent schedules of negative reinforcement on compliance and aberrant behavior

Prior research has suggested that fixed-time (FT) schedules of reinforcement do not necessarily preclude the acquisition of appropriate behavior (e.g., mands) when combined with differential reinforcement (DRA). These studies also note that dense FT schedules are more likely to interfere with DRA packages than lean FT schedules. In the current investigation, we examined whether similar findings would occur with FT schedules of negative reinforcement. Schedule analyses were conducted with two participants following functional analyses that identified escape from task demands as the maintaining variable for problem behavior. Differential negative reinforcement of alternative behavior (DNRA) was implemented first to establish behavioral control (decreased problem behavior and increased compliance). Breaks (negative reinforcement) were then concurrently delivered on a FT basis under either dense (at a greater rate than that obtained during DNRA alone) or lean (at a lower rate than that obtained during DNRA) reinforcement schedules. In general, results showed that FT escape did not preclude compliance when the FT schedule was lean, but treatment gains were significantly disrupted when dense FT schedules were superimposed.

Modifying the behaviour of singly caged baboons: evaluating the effectiveness of four enrichment techniques

Techniques to reduce or prevent behavioural disturbances in singly caged primates vary in form and effectiveness, with some behaviours being exceptionally resistant to treatment. Seven singly caged adolescent male olive hybrid baboons (Papio hamadryas anubis) were selected for behavioural intervention because of their severe abnormal behaviour. A continuous, all-occurrence sampling method yielded mean durations of abnormal and normal behaviour throughout the 10-week study. Analysis of baseline behaviour verified substantial durations of abnormal behaviour (mean = 9.80 min per 30-min observation period). We tested the effectiveness of four enrichment techniques: positive reinforcement training (PRT), food enrichment, non-food enrichment, and social enrichment (pair/trio housing). Each of the four enrichment conditions was implemented for a two-week period, with 10 30-min observations conducted per subject. We used repeated-measures analysis of variance to examine differences in behaviour durations between baseline and each enrichment condition. The social enrichment condition resulted in the most positive behavioural changes, including increased social behaviour and near elimination of abnormal behaviours (mean = 0.69 min per 30-min observation). Significant reductions in total abnormal behaviour levels were also found for other types of enrichment, but only social enrichment and PRT were effective in reducing whole-body stereotypies. Cage-directed and self-directed behaviours significantly decreased, whereas activity levels significantly increased during all enrichment conditions. The results of this project indicate that animate enrichment (human or conspecific stimulation), as opposed to inanimate enrichment, provides optimal means of behaviour modification for singly caged baboons. These findings have substantial implications for the welfare of captive primates in promoting successful therapeutic approaches for the behavioural management of laboratory primate species and for allocating limited enrichment resources.

On the relative contributions of noncontingent reinforcement and escape extinction in the treatment of food refusal

In the current investigation, we evaluated the relative effects of noncontingent reinforcement (NCR), escape extinction, and a combination of NCR and escape extinction as treatment for the feeding problems exhibited by 4 children. For each participant, consumption increased only when escape extinction was implemented, independent of whether NCR was present or absent. These results were consistent with prior research suggesting that positive reinforcement alone is insufficient for increasing consumption, and that escape extinction often is necessary to increase and maintain food acceptance. However, NCR appeared to decrease inappropriate behavior for some participants.

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.