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The effects of delivering nondrug alternative reinforcement on resistance to extinction and reinstatement of rats' ethanol-maintained lever pressing were evaluated in two experiments. In both, rats self-administered ethanol by lever pressing in a two-component multiple schedule during baseline. In the Rich component, alternative food reinforcement was made available for performing an alternative response (Experiment 1) or according to a differential-reinforcement-of-other-behavior schedule for lever pressing (Experiment 2). In the Lean component, only ethanol was available. Moreover, the frequency of alternative reinforcement was manipulated across conditions in Experiment 1. Following baseline, lever pressing was extinguished in both components by suspending ethanol reinforcement, and alternative food reinforcers were discontinued. Finally, to test for reinstatement, ethanol reinforcers were delivered independently of lever pressing in both components. In both experiments, proportion-of-baseline response rates were higher during extinction and reinstatement testing in the Rich component than in the Lean component (although differentiation was not observed at the lowest frequency of alternative reinforcement in Experiment 1). Thus, alternative nondrug reinforcers increased resistance to extinction and reinstatement of rats' ethanol-maintained lever pressing, even when those reinforcers were delivered contingently on an alternative response or on abstinence from lever pressing.

Resurgence is observed when a previously extinguished behavior reemerges while a more recently reinforced behavior is extinguished. Resurgence is further defined as responding that is greater than an inactive control response that has never produced reinforcement. Recent studies of resurgence using neurotypical adults as participants in human-laboratory investigations have produced discrepant patterns of responding compared to nonhuman animal laboratory studies when comparing control response performance. Namely, human-laboratory investigations have produced no differences between target and control responding, and persistence of all response types across the resurgence-test phase. In the present study, we conducted two human-laboratory experiments to determine if these effects were a product of the history of reinforcement associated with the target response as well as the types of technology used in human-laboratory studies. For all participants, we found no differences in levels of resurgence and occurrence for the target and control response, respectively. Moreover, we observed persistence of all response types across the resurgence-test phase in a manner consistent with prior research. This finding was apparent even when the length of baseline (i.e., reinforcement for the target) was increased, when the length of extinction was increased, and when low-technology stimuli were used. We highlight the implications of this outcome in the context of recent human-laboratory studies that have used arbitrary responses to study resurgence, and discuss the possible role of verbal mediation in these investigations.

Clinicians frequently prescribe functional communication training (FCT) as a treatment for severe destructive behavior. Recent research has shown that FCT treatments are susceptible to treatment relapse in the form of resurgence of destructive behavior when individuals contact periods in which reinforcers are unavailable. Results of preliminary studies suggest that teaching multiple response alternatives can mitigate the resurgence of target behavior. The current evaluation serves as a preliminary study in which we used a laboratory arrangement to evaluate the effects of a novel approach to training multiple alternative responses on the resurgence of target behavior. Findings showed that multiple-response training did not decrease resurgence of target responding consistently; however, it increased the total amount of target and alternative responding observed during the resurgence phase and decreased the overall probability of the target response.

Basic-laboratory assessments of renewal may inform clinical efforts to maintain reduction of severe destructive behavior when clients transition between contexts. The contextual changes arranged during standard renewal procedures, however, do not necessarily align with those that clients experience during outpatient therapy. More specifically, clients transition between clinical (associated with extinction for target behavior) and home/community (associated with reinforcement for target behavior) contexts during outpatient treatment. Standard renewal assessments do not incorporate these contextual alternations during treatment. The present experiment aimed to directly compare renewal of rats' lever pressing following a standard ("sequential") ABA renewal procedure (i.e., baseline in Context A, extinction in Context B, renewal test in Context A) and a "nonsequential" renewal assessment wherein treatment consisted of daily alternation between Context A (associated with reinforcement for lever pressing) and Context B (associated with extinction). Lever pressing renewed to a greater extent for rats in the Nonsequential group than for rats in the Sequential group, suggesting the contextual changes that clients experience during outpatient treatment for severe destructive behavior may be a variable that is important to consider in translational research on renewal. Potential implications of these findings for basic and clinical research on renewal are discussed.

Randomization statistics offer alternatives to many of the statistical methods commonly used in behavior analysis and the psychological sciences, more generally. These methods are more flexible than conventional parametric and nonparametric statistical techniques in that they make no assumptions about the underlying distribution of outcome variables, are relatively robust when applied to small-n data sets, and are generally applicable to between-groups, within-subjects, mixed, and single-case research designs. In the present article, we first will provide a historical overview of randomization methods. Next, we will discuss the properties of randomization statistics that may make them particularly well suited for analysis of behavior-analytic data. We will introduce readers to the major assumptions that undergird randomization methods, as well as some practical and computational considerations for their application. Finally, we will demonstrate how randomization statistics may be calculated for mixed and single-case research designs. Throughout, we will direct readers toward resources that they may find useful in developing randomization tests for their own data.

In functional assessment, challenging behavior is categorized by the purpose that it serves for the individual. This is accomplished by assessing the environmental variables that precede (antecedents) and follow (consequences) the occurrence of challenging behavior. Functions are then established by identifying systematic behavior-environment relations. The purpose of the current chapter is to describe the ways in which functions of challenging behavior are identified during the assessment process. We begin by providing a brief overview of various functional-assessment strategies. Next, we describe common functions of challenging behavior and present them according to their corresponding category of reinforcement (i.e., social-positive, social-negative, and automatic reinforcement). Finally, we discuss the clinical implications of functional assessment in terms of treatment utility.

Parents play an important role in the treatment of their children's symptoms of autism spectrum disorder (ASD); thus, developing effective, efficient, socially acceptable, and accessible procedures for training parents to implement applied-behavior-analysis (ABA) interventions is critically important. One potential approach involves delivering training via a virtual private network (VPN) over the internet (Fisher et al., 2014). In this study, we conducted a randomized clinical trial to evaluate a virtual parent-training program with e-learning modules and scripted role-play via a VPN. We evaluated parent implementation of ABA skills using direct-observation measures in structured-work and play-based training contexts. Parents in the treatment group showed large, statistically significant improvements on all dependent measures; those in the waitlist-control group did not. Parents rated the training as highly socially acceptable. Results add to the growing literature on the efficacy and acceptability of virtually delivered training in ABA.

Individuals diagnosed with intellectual disability (ID) are at increased risk for the development of challenging behaviors. Common forms of challenging behaviors presented by individuals with ID include self-injurious behavior (SIB), rituals, and stereotypies. The prevalence of challenging behaviors often increases throughout childhood and adolescence. Further, challenging behaviors can result in detrimental consequences. Therefore, prevention and effective treatment for challenging behaviors is essential for improving the lives of individuals with ID.

Concepts from behavioral momentum theory, along with some empirical findings, suggest that the rate of baseline reinforcement may contribute to the relapse of severe destructive behavior. With seven children who engaged in destructive behavior, we tested this hypothesis in the context of functional communication training by comparing the effects of different baseline reinforcement rates on resurgence during a treatment challenge (i.e., extinction). We observed convincing resurgence of destructive behavior in four of seven participants, and we observed more resurgence in the condition associated with high-rate baseline reinforcement (i.e., variable-interval 2 s in Experiment 1 or fixed-ratio 1 in Experiment 2) compared to a low-rate baseline reinforcement condition. We discuss the implications of these results relative to schedules of reinforcement in the treatment of destructive behavior and strategies to mitigate resurgence in clinical settings.

Delivery of alternative reinforcers in the presence of stimuli previously associated with reinforcement for target behavior increases the susceptibility of target behavior to relapse. To explore contingencies that might mitigate this counter-therapeutic effect, we trained pigeons on a procedure that entailed extinction of previously reinforced target-key pecking, access to a distinct stimulus context contingently on refraining from target behavior (differential-reinforcement-of-other-behavior; DRO), and reinforcement of alternative-key pecks (differential-reinforcement of alternative behavior; DRA) in that context. This DRO-DRA treatment was compared with standard DRA in successive conditions, counterbalanced across pigeons. Target behavior extinguished more rapidly in the Standard-DRA condition. When alternative reinforcement was discontinued, however, there was less resurgence after DRO-DRA than after Standard DRA. In a third condition, the DRO contingency was suspended so that the former DRA stimuli were not presented (DRO-NAC), and resurgence was greater than in the Standard-DRA and DRO-DRA conditions. Reinstatement produced by response-independent reinforcers was small and similar across conditions. Subsequent reacquisition of target-key pecking under baseline reinforcement conditions was faster following DRO-NAC than Standard-DRA or DRO-DRA. These findings suggest that DRO-DRA might serve as a useful method in clinical settings for reducing problem behavior while minimizing the threat of posttreatment relapse.

Spontaneous recovery occurs when a previously reinforced and recently extinguished response reemerges over the course of time, often at the beginning of a new session of extinction. Spontaneous recovery could underlie instances of treatment relapse that threaten otherwise effective behavioral interventions for problem behavior. In two experiments, we arranged multiple schedules with pigeons and a human child to assess the effects of different training reinforcer rates on spontaneous recovery. In both experiments, responding was both more resistant to extinction and more likely to relapse following training with greater reinforcement rates upon returning to extinction after time off from extinction testing. A quantitative model based on behavioral momentum theory accounted well for the data, which suggests reexposure to the extinction context following time off during extinction resulted in (1) the failure of extinction learning to generalize, and (2) greater generalization of original learning during training. The present model attempts to quantify theories attributing spontaneous recovery to changes in temporal context.

Resistance to extinction in a target multiple-schedule component varies inversely with the rate of reinforcement arranged in an alternative component during baseline. The present experiment asked whether changing the reinforcer rate in an alternative component would impact extinction of target component responding if those changes occurred in an off-baseline phase during which the target component was never experienced. Pigeons' key pecking was studied in three types of conditions, and each condition consisted of three phases. In Phase 1, pecking produced food in the target and alternative components of a multiple schedule according to variable-interval 60-s schedules. In Phase 2, the alternative-component stimulus was presented alone in a single schedule. Pecking during this phase produced the same reinforcer rate as in baseline in the Control condition, a higher rate of food (variable-interval 15 s) in the High-Rate condition, or was extinguished in the Extinction condition. Extinction of target- and alternative-component key pecking then was assessed in a multiple schedule during the final phase of each condition. Resistance to extinction of target-component key pecking was the same between the Control and High-Rate conditions but lower in the Extinction condition. These findings are discussed in terms of discrimination and generalization processes.

Resurgence refers to the recurrence of an extinguished target behavior following subsequent suspension of alternative reinforcement. Delivery of reinforcers during extinction of alternative behavior has been shown to mitigate resurgence. The present experiment aimed to determine whether delivering stimuli associated with reinforcers during resurgence testing similarly mitigates resurgence. Three groups of rats pressed target levers for food according to variable-interval 15-s schedules during Phase 1. In Phase 2, lever pressing was extinguished, and an alternative nose-poke response produced alternative reinforcement according to a variable-interval 15-s schedule. Food reinforcement was always associated with illumination of the food aperture and an audible click from the pellet dispenser during Phases 1 and 2. Phase 3 treatments differed between groups. For one group, nose poking continued to produce food and food-correlated stimuli. Both of these consequences were suspended for a second group. Finally, nose poking produced food-correlated stimuli but not food for a third group. Target-lever pressing resurged in the group that received no consequences and in the group that received only food-correlated stimuli for nose poking. Resurgence, however, was smaller for the group that received food-correlated stimuli than for the group that received no consequences for nose poking. Target-lever pressing did not increase between phases in the group that continued to receive food and associated stimuli. Thus, delivery of stimuli associated with food reinforcement after suspension of food reduced but did not eliminate resurgence of extinguished lever pressing. These findings contribute to potential methodologies for preventing relapse of extinguished problem behavior in clinical settings.

Resurgence is typically defined as an increase in a previously extinguished target behavior when a more recently reinforced alternative behavior is later extinguished. Some treatments of the phenomenon have suggested that it might also extend to circumstances where either the historic or more recently reinforced behavior is reduced by other non-extinction related means (e.g., punishment, decreases in reinforcement rate, satiation, etc.). Here we present a theory of resurgence suggesting that the phenomenon results from the same basic processes governing choice. In its most general form, the theory suggests that resurgence results from changes in the allocation of target behavior driven by changes in the values of the target and alternative options across time. Specifically, resurgence occurs when there is an increase in the relative value of an historically effective target option as a result of a subsequent devaluation of a more recently effective alternative option. We develop a more specific quantitative model of how extinction of the target and alternative responses in a typical resurgence paradigm might produce such changes in relative value across time using a temporal weighting rule. The example model does a good job in accounting for the effects of reinforcement rate and related manipulations on resurgence in simple schedules where Behavioral Momentum Theory has failed. We also discuss how the general theory might be extended to other parameters of reinforcement (e.g., magnitude, quality), other means to suppress target or alternative behavior (e.g., satiation, punishment, differential reinforcement of other behavior), and other factors (e.g., non- contingent versus contingent alternative reinforcement, serial alternative reinforcement, and multiple schedules).

Resurgence is defined as an increase in the frequency of a previously reinforced target response when an alternative source of reinforcement is suspended. Despite an extensive body of research examining factors that affect resurgence, the effects of alternative-reinforcer magnitude have not been examined. Thus, the present experiments aimed to fill this gap in the literature. In Experiment 1, rats pressed levers for single-pellet reinforcers during Phase 1. In Phase 2, target-lever pressing was extinguished, and alternative-lever pressing produced either five-pellet, one-pellet, or no alternative reinforcement. In Phase 3, alternative reinforcement was suspended to test for resurgence. Five-pellet alternative reinforcement produced faster elimination and greater resurgence of target-lever pressing than one-pellet alternative reinforcement. In Experiment 2, effects of decreasing alternative-reinforcer magnitude on resurgence were examined. Rats pressed levers and pulled chains for six-pellet reinforcers during Phases 1 and 2, respectively. In Phase 3, alternative reinforcement was decreased to three pellets for one group, one pellet for a second group, and suspended altogether for a third group. Shifting from six-pellet to one-pellet alternative reinforcement produced as much resurgence as suspending alternative reinforcement altogether, while shifting from six pellets to three pellets did not produce resurgence. These results suggest that alternative-reinforcer magnitude has effects on elimination and resurgence of target behavior that are similar to those of alternative-reinforcer rate. Thus, both suppression of target behavior during alternative reinforcement and resurgence when conditions of alternative reinforcement are altered may be related to variables that affect the value of the alternative-reinforcement source.

Previous work from our laboratory showed that intermittently re-exposing rats to reinforcement for lever pressing in a training (A) context, while eliminating lever pressing in a second (B) context, increased ABA renewal of lever pressing relative to rats that experienced only Context B during response elimination. In the current study, we replicated these procedures while assessing renewal in the presence of a novel context (i.e., ABC renewal). Unlike the findings described above, renewal was reduced in the group that experienced re-exposure to Context A during lever-press elimination relative to rats that experienced only Context B. These findings suggest that alternating between contexts associated with reinforcement and extinction during treatment reduces the probability that organisms will respond in novel contexts. These outcomes may be the result of discrimination and/or generalization processes. Moreover, this training procedure may offer a potential mitigation strategy for ABC renewal.

Contingency is a critical concept for theories of associative learning and the assignment of credit problem in reinforcement learning. Measuring and manipulating it has, however, been problematic. The information-theoretic definition of contingency-normalized mutual information-makes it a readily computed property of the relation between reinforcing events, the stimuli that predict them and the responses that produce them. When necessary, the dynamic range of the required temporal representation divided by the Weber fraction gives a psychologically realistic plug-in estimates of the entropies. There is no measurable prospective contingency between a peck and reinforcement when pigeons peck on a variable interval schedule of reinforcement. There is, however, a perfect retrospective contingency between reinforcement and the immediately preceding peck. Degrading the retrospective contingency by gratis reinforcement reveals a critical value (.25), below which performance declines rapidly. Contingency is time scale invariant, whereas the perception of proximate causality depends-we assume-on there being a short, fixed psychologically negligible critical interval between cause and effect. Increasing the interval between a response and reinforcement that it triggers degrades the retrograde contingency, leading to a decline in performance that restores it to at or above its critical value. Thus, there is no critical interval in the retrospective effect of reinforcement. We conclude with a short review of the broad explanatory scope of information-theoretic contingencies when regarded as causal variables in conditioning. We suggest that the computation of contingencies may supplant the computation of the sum of all future rewards in models of reinforcement learning. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The present experiments assessed whether resistance to extinction of pigeons' key pecking decreased across repeated extinction tests. An additional impetus for this research was to determine how the quantitative framework provided by behavioral momentum theory might be used to describe any such changes across tests. Pigeons pecked keys in two-component multiple schedules (one component associated with a higher reinforcer rate and the other with a lower rate) in which baseline and extinction conditions alternated. In Experiment 1, baseline and extinction conditions alternated every session, and, in Experiment 2, these conditions lasted for 10 and 7 sessions, respectively. Resistance to extinction decreased across successive extinction conditions in both experiments. Fits of the behavioral-momentum based model of extinction to the data returned uncertain results in Experiment 1 but implicated both generalization decrement and response-reinforcer contingency termination as the possible mechanisms responsible for behavior change in Experiment 2. Thus, these data suggest that experimental manipulations that affect discrimination of changes in reinforcement contingencies may influence resistance to extinction by modulating the disruptive impacts of removing reinforcers from the experimental context and of suspending response-reinforcer contingencies.

Three experiments explored the impact of different reinforcer rates for alternative behavior (DRA) on the suppression and post-DRA relapse of target behavior, and the persistence of alternative behavior. All experiments arranged baseline, intervention with extinction of target behavior concurrently with DRA, and post-treatment tests of resurgence or reinstatement, in two- or three-component multiple schedules. Experiment 1, with pigeons, arranged high or low baseline reinforcer rates; both rich and lean DRA schedules reduced target behavior to low levels. When DRA was discontinued, the magnitude of relapse depended on both baseline reinforcer rate and the rate of DRA. Experiment 2, with children exhibiting problem behaviors, arranged an intermediate baseline reinforcer rate and rich or lean signaled DRA. During treatment, both rich and lean DRA rapidly reduced problem behavior to low levels, but post-treatment relapse was generally greater in the DRA-rich than the DRA-lean component. Experiment 3, with pigeons, repeated the low-baseline condition of Experiment 1 with signaled DRA as in Experiment 2. Target behavior decreased to intermediate levels in both DRA-rich and DRA-lean components. Relapse, when it occurred, was directly related to DRA reinforcer rate as in Experiment 2. The post-treatment persistence of alternative behavior was greater in the DRA-rich component in Experiment 1, whereas it was the same or greater in the signaled-DRA-lean component in Experiments 2 and 3. Thus, infrequent signaled DRA may be optimal for effective clinical treatment.

Owing in part to the implications of resurgence for issues surrounding human health and adaptive problem solving, a substantial amount of laboratory research has been dedicated to understanding why this form of relapse occurs and what factors affect it. This research, however, has never been extended to mice, leaving unknown the specific experimental parameters that are appropriate for studying resurgence in this species. Two experiments were conducted in which mice were exposed to a three-phase resurgence preparation in a multiple-baseline-across-subjects design. In Phase 1, pressing a target lever produced food according to a variable-interval 15-s schedule. In Phase 2, target-lever pressing was extinguished, and nose poking produced reinforcement according to either a variable-interval 15-s (Experiment 1) or fixed-ratio 1 (Experiment 2) schedule. Finally, alternative reinforcement was suspended to test for resurgence. Lever pressing relapsed for one of four mice in Experiment 1, but all four mice demonstrated relapse in Experiment 2. Thus, relatively dense schedules of alternative reinforcement may be required to reliably study resurgence of previously reinforced responding in mice. These findings are instructive for researchers who are interested in studying resurgence of mice’s behavior and further demonstrate the cross-species generality of this form of relapse.

Resurgence occurs when a previously extinguished behavior reemerges once a more recently reinforced behavior is placed on extinction. Previous research has suggested that nontargeted responses within the same response class recur alongside target-response resurgence (e.g., da Silva, Maxwell, & Lattal, 2008; Lieving, Hagopian, Long, & O'Connor, 2004). The purpose of this two-experiment investigation was to examine target response resurgence while simultaneously measuring the occurrence of nontargeted responses. Three children diagnosed with autism spectrum disorder who displayed multiple topographies of problem behavior participated. In Experiment 1, a three-phase resurgence procedure was conducted and all three participants displayed target-response resurgence accompanied by the emergence of nontargeted forms of problem behavior. These findings were replicated in Experiment 2 using a 30-min assessment procedure. The implications of these findings as they pertain to the treatment of severe problem behavior and utility of a brief relapse assessment are discussed.

In the clinic, differential reinforcement of alternative behavior (DRA) often involves programming extinction for destructive behavior while reinforcing an alternative form of communication (e.g., a functional communication response); however, implementing extinction can be unsafe or impractical under some circumstances. Quantitative theories of resurgence (i.e., Behavioral Momentum Theory and Resurgence as Choice) predict differences in the efficacy of treatments that do and do not involve extinction of target responding when reinforcement conditions maintaining alternative responding worsen. We tested these predictions by examining resurgence following two DRA conditions in which we equated rates of reinforcement. In DRA without extinction, target and alternative behavior produced reinforcement. In DRA with extinction plus noncontingent reinforcement, only alternative behavior produced reinforcement. We conducted this study in a reverse-translation sequence, first with participants who engaged in destructive behavior (Experiment 1) and then in a laboratory setting with rats (Experiment 2). Across both experiments, we observed proportionally lower levels of target responding during and following the DRA condition that arranged extinction for the target response. However, levels of resurgence were similar following both arrangements.

Concepts from behavioral momentum theory, along with some empirical findings, suggest that the rate of baseline reinforcement may contribute to the relapse of severe destructive behavior. With seven children who engaged in destructive behavior, we tested this hypothesis in the context of functional communication training by comparing the effects of different baseline reinforcement rates on resurgence during a treatment challenge (i.e., extinction). We observed convincing resurgence of destructive behavior in four of seven participants, and we observed more resurgence in the condition associated with high-rate baseline reinforcement (i.e., variable-interval 2 s in Experiment 1 or fixed-ratio 1 in Experiment 2) compared to a low-rate baseline reinforcement condition. We discuss the implications of these results relative to schedules of reinforcement in the treatment of destructive behavior and strategies to mitigate resurgence in clinical settings.

Provision of alternative non-drug reinforcement is among the most effective methods for treating substance use disorders. However, when alternative reinforcers become unavailable during treatment interruptions or upon cessation of treatment, relapse often occurs. Relapse following the loss of alternative reinforcement is known as resurgence. One factor that could reduce resurgence is longer duration of treatment with alternative reinforcement, but the available data are mixed. Further, the effects of length of treatment have previously only been examined with food seeking. The present experiments directly examined if duration of treatment impacted the magnitude of resurgence of cocaine or alcohol seeking in rats. First, rats were trained to self-administer cocaine (Experiment 1) or alcohol (Experiment 2) by performing a target behavior. Second, target behavior was extinguished and performing an alternative behavior produced an alternative non-drug (i.e., food) reinforcer. Finally, resurgence was assessed following removal of alternative reinforcement after either 5 or 20 sessions of treatment. Treatment duration did not differentially affect resurgence of cocaine seeking in Experiment 1 or Alcohol seeking in Experiment 2. These results suggest that extended treatment with alternative non-drug reinforcement may not decrease propensity to relapse. Further, these results may have implications for treatment of substance use disorders and for theories of resurgence.

Spontaneous recovery occurs when a previously reinforced and recently extinguished response reemerges over the course of time, often at the beginning of a new session of extinction. Spontaneous recovery could underlie instances of treatment relapse that threaten otherwise effective behavioral interventions for problem behavior. In two experiments, we arranged multiple schedules with pigeons and a human child to assess the effects of different training reinforcer rates on spontaneous recovery. In both experiments, responding was both more resistant to extinction and more likely to relapse following training with greater reinforcement rates upon returning to extinction after time off from extinction testing. A quantitative model based on behavioral momentum theory accounted well for the data, which suggests reexposure to the extinction context following time off during extinction resulted in (1) the failure of extinction learning to generalize, and (2) greater generalization of original learning during training. The present model attempts to quantify theories attributing spontaneous recovery to changes in temporal context.

We summarize the results of four recent translational studies from our lab that used the predictions of behavioral momentum theory to inform the development of more durable treatments for destructive behavior. Treatments informed by behavioral momentum theory generally showed better suppression of target responding during an extinction challenge than did a comparison treatment. We re-analyze data from each of the four studies to show that this general finding is apparent both at the aggregate (i.e., proportion of baseline response rates averaged across participants) and within participant (i.e., percentage reduction in proportion of baseline response rates, difference in raw response rates during the extinction challenge). Interestingly, participants who experienced multiple cycles of the extinction challenge generally showed less differentiation in target responding between the theory informed by behavioral momentum treatment and the comparison treatment. Overall results suggest that applications of behavioral momentum theory can substantially improve the durability of common treatments for destructive behavior.

"Resistance to change" represents a core symptom of autism that we conceptualized and assessed as resulting in part due to factors known to govern free-operant choice. During a free-choice baseline, participants chose between problematic, resistive responses and an appropriate alternative response. During the asymmetrical-choice condition, we delivered their most highly preferred item if the participant chose the alternative response (i.e., differential reinforcement of alternative behavior [DRA]). During the guided- (Experiment 1) and singular- (Experiment 2) choice conditions, we prompted participants to choose the alternative response and then delivered their most highly preferred item (i.e., DRA with escape extinction). All participants learned to tolerate (Experiment 1) or choose (Experiment 2) the alternative response when we combined DRA with escape extinction. After exposure to escape extinction, two participants showed strong maintenance effects with DRA alone. We discuss these finding relative to the effects of DRA and escape extinction on resistance to change.

The effects of intermittent schedules of reinforcement for pausing were evaluated in two experiments. In Experiment 1, across a series of conditions, a variable-interval (VI) baseline schedule, in which pigeons' key pecks produced food, alternated with conditions in which food was delivered according to a concurrent VI (for key pecking) tandem variable-time differential-reinforcement-of-other-behavior (DRO) 5-s schedule. Time spent pausing within a session was proportional to the reinforcement rates associated with the tandem schedule. To examine the control of pausing by antecedent events, Experiment 2 arranged a multiple schedule in which pecking and pausing in either component were maintained according to concurrent schedules like those used in the first experiment. The availability of reinforcement for pausing was signaled in one component while signals uncorrelated with reinforcement were presented in the other. Signaled reinforcement for pausing, relative to the presentation of uncorrelated signals, decreased time spent pausing, a finding consistent with existing research on the effects of signaled VI reinforcement for key pecking in pigeons. The results of the two experiments show that pausing functions as an operant in much the same way that discrete responses, like key pecks, do, and that pausing and other operants are similarly affected by both antecedent and consequent events.

Delivery of alternative reinforcers in the presence of stimuli previously associated with reinforcement for target behavior increases the susceptibility of target behavior to relapse. To explore contingencies that might mitigate this counter-therapeutic effect, we trained pigeons on a procedure that entailed extinction of previously reinforced target-key pecking, access to a distinct stimulus context contingently on refraining from target behavior (differential-reinforcement-of-other-behavior; DRO), and reinforcement of alternative-key pecks (differential-reinforcement of alternative behavior; DRA) in that context. This DRO-DRA treatment was compared with standard DRA in successive conditions, counterbalanced across pigeons. Target behavior extinguished more rapidly in the Standard-DRA condition. When alternative reinforcement was discontinued, however, there was less resurgence after DRO-DRA than after Standard DRA. In a third condition, the DRO contingency was suspended so that the former DRA stimuli were not presented (DRO-NAC), and resurgence was greater than in the Standard-DRA and DRO-DRA conditions. Reinstatement produced by response-independent reinforcers was small and similar across conditions. Subsequent reacquisition of target-key pecking under baseline reinforcement conditions was faster following DRO-NAC than Standard-DRA or DRO-DRA. These findings suggest that DRO-DRA might serve as a useful method in clinical settings for reducing problem behavior while minimizing the threat of posttreatment relapse.

We review quantitative accounts of behavioral momentum theory (BMT), its application to clinical treatment, and its extension to post-intervention relapse of target behavior. We suggest that its extension can account for relapse using reinstatement and renewal models, but that its application to resurgence is flawed both conceptually and in its failure to account for recent data. We propose that the enhanced persistence of target behavior engendered by alternative reinforcers is limited to their concurrent availability within a distinctive stimulus context. However, a failure to find effects of stimulus-correlated reinforcer rates in a Pavlovian-to-Instrumental Transfer (PIT) paradigm challenges even a straightforward Pavlovian account of alternative reinforcer effects. BMT has been valuable in understanding basic research findings and in guiding clinical applications and accounting for their data, but alternatives are needed that can account more effectively for resurgence while encompassing basic data on resistance to change as well as other forms of relapse.

Relapse following removal of an alternative source of reinforcement introduced during extinction of a target behavior is called resurgence. This form of relapse may be related to relapse of drug taking following loss of alternative non-drug reinforcement in human populations. Laboratory investigations of factors mediating resurgence with food-maintained behavior suggest higher rates of alternative reinforcement produce faster suppression of target behavior but paradoxically generate more relapse when alternative reinforcement is discontinued. At present, it is unknown if a similar effect occurs when target behavior is maintained by drug reinforcement and the alternative is a non-drug reinforcer. In the present experiment three groups of rats were trained to lever press for infusions of cocaine during baseline. Next, during treatment, cocaine reinforcement was suspended and an alternative response was reinforced with either high-rate, low-rate, or no alternative food reinforcement. Finally, all reinforcement was suspended to test for relapse of cocaine seeking. Higher rate alternative reinforcement produced faster elimination of cocaine seeking than lower rates or extinction alone, but when treatment was suspended resurgence of cocaine seeking occurred following only high-rate alternative reinforcement. Thus, although higher rate alternative reinforcement appears to more effectively suppress drug seeking, should it become unavailable, it can have the unfortunate effect of increasing relapse.

The behavioral-momentum model of resurgence predicts reinforcer rates within a resurgence preparation should have three effects on target behavior. First, higher reinforcer rates in baseline (Phase 1) produce more persistent target behavior during extinction plus alternative reinforcement. Second, higher rate alternative reinforcement during Phase 2 generates greater disruption of target responding during extinction. Finally, higher rates of either reinforcement source should produce greater responding when alternative reinforcement is suspended in Phase 3. Recent empirical reports have produced mixed results in terms of these predictions. Thus, the present experiment further examined reinforcer-rate effects on persistence and resurgence. Rats pressed target levers for high-rate or low-rate variable-interval food during Phase 1. In Phase 2, target-lever pressing was extinguished, an alternative nose-poke became available, and nose-poking produced either high-rate variable-interval, low-rate variable-interval, or no (an extinction control) alternative reinforcement. Alternative reinforcement was suspended in Phase 3. For groups that received no alternative reinforcement, target-lever pressing was less persistent following high-rate than low-rate Phase-1 reinforcement. Target behavior was more persistent with low-rate alternative reinforcement than with high-rate alternative reinforcement or extinction alone. Finally, no differences in Phase-3 responding were observed for groups that received either high-rate or low-rate alternative reinforcement, and resurgence occurred only following high-rate alternative reinforcement. These findings are inconsistent with the momentum-based model of resurgence. We conclude this model mischaracterizes the effects of rein-forcer rates on persistence and resurgence of operant behavior.

Habitual behaviors, such as problematic nail biting, are a common target for self-managed behavior-modification programs. The current self-experiment used self-monitoring in conjunction with a self-managed differential-reinforcement procedure for the treatment of problematic nail biting. A simple picture-comparison procedure allowed an independent observer to assist in monitoring treatment progress and outcomes and to ensure treatment integrity. Results provide support that the overall treatment package was successful in decreasing the occurrence of nail biting. Moreover, the treatment-integrity procedure enabled full-day monitoring to take place with limited requirement of a secondary observer.

The ability of organisms to detect reinforcer-rate changes in choice preparations is positively related to two factors: the magnitude of the change in rate and the frequency with which rates change. Gallistel (2012) suggested similar rate-detection processes are responsible for decreases in responding during operant extinction. Although effects of magnitude of change in reinforcer rate on resistance to extinction are well known (e.g., the partial-reinforcement-extinction effect), effects of frequency of changes in rate prior to extinction are unknown. Thus, the present experiments examined whether frequency of changes in baseline reinforcer rates impacts resistance to extinction. Pigeons pecked keys for variable-interval food under conditions where reinforcer rates were stable and where they changed within and between sessions. Overall reinforcer rates between conditions were controlled. In Experiment 1, resistance to extinction was lower following exposure to dynamic reinforcement schedules than to static schedules. Experiment 2 showed that resistance to presession feeding, a disruptor that should not involve change-detection processes, was unaffected by baseline-schedule dynamics. These findings are consistent with the suggestion that change detection contributes to extinction. We discuss implications of change-detection processes for extinction of simple and discriminated operant behavior and relate these processes to the behavioral-momentum based approach to understanding extinction.

Delay discounting describes the subjective devaluation of a reward when it is delayed. In animals, the adjusting- and increasing-delay tasks often are used to assess individual differences in, and drug effects on, delay discounting. No study to date, however, has compared systematically the measures of discounting produced in these tasks. The current study examined the correlation between measures of delay discounting derived from adjusting- and increasing-delay procedures. Twenty rats completed 30 sessions under each task (order counterbalanced across rats). Quantitative measures of delay discounting produced by the two tasks were positively correlated, suggesting that the adjusting-and increasing-delay tasks measure the same underlying facet of impulsive choice (i.e., individual or conjoint sensitivities to reward delay and magnitude). The measures derived from either task, however, depended on the sequences in which the tasks were experienced. That is, pre-exposure to one task decreased discounting of delayed rewards in the second task. Consistent with other published findings, exposure to delayed consequences during the initial discounting assessment might explain this effect. Despite the observed correlation between ID and AD indifference delays, we suggest that the ID procedure might be a more appropriate procedure for pharmacological studies.

The effects of intermittent schedules of reinforcement for pausing were evaluated in two experiments. In Experiment 1, across a series of conditions, a variable-interval (VI) baseline schedule, in which pigeons' key pecks produced food, alternated with conditions in which food was delivered according to a concurrent VI (for key pecking) tandem variable-time differential-reinforcement-of-other-behavior (DRO) 5-s schedule. Time spent pausing within a session was proportional to the reinforcement rates associated with the tandem schedule. To examine the control of pausing by antecedent events, Experiment 2 arranged a multiple schedule in which pecking and pausing in either component were maintained according to concurrent schedules like those used in the first experiment. The availability of reinforcement for pausing was signaled in one component while signals uncorrelated with reinforcement were presented in the other. Signaled reinforcement for pausing, relative to the presentation of uncorrelated signals, decreased time spent pausing, a finding consistent with existing research on the effects of signaled VI reinforcement for key pecking in pigeons. The results of the two experiments show that pausing functions as an operant in much the same way that discrete responses, like key pecks, do, and that pausing and other operants are similarly affected by both antecedent and consequent events.

A hydraulic model is being used to simulate 1400 km of the Orange River, the largest river in southern Africa, south of the Zambezi and one of South Africa’s most important water resources. The system will be used as a decision support tool in the operation of the river so that the supply of water to the lower Orange River can be optimised. By incorporating real time telemetry flow and stage data into the model the forecast flows in the river are improved.