ANALYSIS OF THE REINFORCEMENT AND EXTINCTION COMPONENTS IN DRO CONTINGENCIES WITH SELF-INJURY

Previous research has shown that self-injurious behavior (SIB) maintained by positive reinforcement may be reduced under differential-reinforcement-of-other-behavior (DRO) contingencies. In this study, we conducted an analysis of the reinforcement and extinction components of DRO while treating the self-injury of 3 women with developmental disabilities. A functional analysis revealed that each subject's SIB was maintained by positive reinforcement in the form of attention. Subsequent reinforcer assessments identified preferred and nonpreferred stimuli for later use in conjunction with DRO. Results showed high rates of SIB for all 3 subjects during baseline, which persisted when DRO was implemented without the relevant extinction component (withholding of attention for SIB) for 2 of the subjects. Low rates of SIB were observed for all subjects when DRO plus extinction was implemented or when extinction was implemented alone, suggesting that extinction may be a critical component of DRO schedules.     

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.     

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.     

Chained and tandem scheduling with children

Children 4 to 7 yr in age were reinforced with trinkets and pennies on chained and tandem schedules. The schedules used were chain DRL FR, chain DRO FR, chain FI FR, tand FI FR, and tand DRO FR. Chain DRL FR and chain DRO FR schedules almost always produced strong schedule and stimulus control, but chain FI FR schedules rarely did if additional techniques were not used. Strong control was produced with chain FI FR schedules, however, if: (a) the FR component was increased in size; (b) schedule and stimulus control was first established with chain DRL FR or chain DRO FR schedules before shifting to the chain FI FR; or (c) an external clock was attached to the FI. Tand FI FR schedules never produced regular or repeatable patterns of responding when additional procedures were not used. Rate patterns resembling those of chain FI FR schedules were produced by tand FI FR schedules, however, if: (a) an external clock was attached to the FI component or (b) control was established by means of tand DRO FR schedules before the tand FI FR was used. Stimulus control was found to be exercised by specific visual stimuli, change of stimuli, and schedule order. Control exercised by schedule order was probably mediated by the child's own behavior which had assumed discriminative stimulus properties.     

Adventitious reinforcement during long-duration DRO exposure

Differential reinforcement of other behavior (DRO) is a procedure often used to decrease problem behavior, but the processes responsible for behavior reduction are not well understood. This study assessed whether adventitious reinforcement of other behavior contributes to DRO effectiveness when, relative to previous research, DRO exposure is prolonged. Two response options were presented on a computer and target responding was reinforced on a variable-ratio schedule. Response rates were then compared during DRO versus yoked variable-time or extinction probes. Across 2 experiments, DRO decreased target responding and increased other responding more than control conditions. However, increases in other responding did not usually maintain despite target responding remaining at low levels. DRO might adventitiously reinforce other responses transiently but the decreases in target behavior could not be entirely explained by adventitious reinforcement of the other response. Instead, reductions in target responding likely depend on the discriminability of the DRO contingency.     

DRO contingencies: an analysis of variable-momentary schedules.

We conducted several comparative analyses to determine the relative effectiveness of variable-momentary differential-reinforcement-of-other-behavior (VM DRO) schedules. Three individuals who had been diagnosed with mental retardation participated. Results of functional analyses indicated that their self-injurious behavior (SIB) was maintained by social-positive reinforcement. Two individuals participated in a two-stage comparative analysis within multielement and multiple baseline designs. Fixed-interval (FI) and variable-interval (VI) DRO were compared in the first stage; VI DRO and VM DRO were compared in the second. All three schedules effectively reduced the participants' SIB. Treatment for the 3rd individual was conducted in a reversal design to examine the effects of VM DRO when it was implemented in isolation, and results indicated that the procedure was effective in reducing SIB. These findings suggest that VM DRO schedules may represent attractive alternatives to traditional FI schedules because momentary schedules do not require continuous monitoring and may result in higher rates of reinforcement.     

A comparison of fixed momentary differential reinforcement of other behavior to variable momentary differential reinforcement of other behavior to reduce challenging behavior

Differential reinforcement of other behavior (DRO) is commonly used to reduce behavioral excesses. Momentary DRO schedules involve delivery of reinforcement contingent upon the absence of the target behavior at a given moment. Two variations of momentary DRO exist: fixed-momentary (FM) DRO and variable-momentary (VM) DRO. In the current study, we directly compared FM-DRO and VM-DRO schedules to reduce challenging behavior maintained by automatic reinforcement exhibited by four children with autism spectrum disorder. The results suggest that both the DRO schedules were equally effective to reduce challenging behavior. A social validity measure showed that most caregivers rated the VM-DRO as a preferred schedule and noted the potential for FM-DRO schedule to become more discriminable over time, which could reduce its effectiveness. However, most caregivers also commented that the FM-DRO schedule was easier to implement.     

“Other” behavior and the DRO: The roles of extinction and reinforcement

Jessel et al. (2015) provided some evidence to suggest that “other” behavior is strengthened in the differential reinforcement of other behavior (DRO). The present study is a systematic replication of the Jessel et al. procedures. The effects of DRO and extinction on target responding, target-other responding (a response with an established history of reinforcement), and nontarget-other responding emitted by children with intellectual and developmental disabilities and children with no known diagnoses were compared. Other behavior increased in at least one DRO condition for each participant, suggesting that other behavior increases when using DRO, at least initially. Under extinction, target responding and target-other responding decreased to low rates for three of the five participants; however, rates of nontarget-other responding were elevated compared to the DRO condition. These results suggest that increased rates of target-other responding and nontarget-other responding during the DRO condition may be a result of extinction-induced variability.     

Comparing fixed‐amount and progressive‐amount DRO Schedules for tic suppression in youth with chronic tic disorders

Chronic tic disorders (CTDs) involve motor and/or vocal tics that often cause substantial distress and impairment. Differential reinforcement of other behavior (DRO) schedules of reinforcement produce robust, but incomplete, reductions in tic frequency in youth with CTDs; however, a more robust reduction may be needed to affect durable clinical change. Standard, fixed‐amount DRO schedules have not commonly yielded such reductions, so we evaluated a novel, progressive‐amount DRO schedule, based on its ability to facilitate sustained abstinence from functionally similar behaviors. Five youth with CTDs were exposed to periods of baseline, fixed‐amount DRO (DRO‐F), and progressive‐amount DRO (DRO‐P). Both DRO schedules produced decreases in tic rate and increases in intertic interval duration, but no systematic differences were seen between the two schedules on any dimension of tic occurrence. The DRO‐F schedule was generally preferred to the DRO‐P schedule. Possible procedural improvements and other future directions are discussed.     

Stimulus control of cocaine self-administration

Environmental stimuli that set the occasion wherein drugs are acquired can "trigger" drug-related behavior. Investigating the stimulus control of drug self-administration in laboratory animals should help us better understand this aspect of human drug abuse. Stimulus control of cocaine self-administration was generated here for the first time using multiple and chained schedules with short, frequently-alternating components--like those typically used to study food-maintained responding. The procedures and results are presented along with case histories to illustrate the strategies used to produce this stimulus control. All these multicomponent schedules contained variable-interval (VI) components as well as differential-reinforcement-of-other-behavior (DRO) or extinction components. Schedule parameters and unit dose were adjusted for each rat to produce stable, moderate rates in VI components, with minimal postreinforcement (infusion) pausing, and response cessation in extinction and DRO components. Whole-body drug levels on terminal baselines calculated retrospectively revealed that all rats maintained fairly stable drug levels (mean, 2.3 to 3.4 mg/kg) and molar rates of intake (approximately 6.0 mg/kg/hr). Within this range, no relation between local VI response rates and drug level was found. The stimulus control revealed in cumulative records was indistinguishable from that achieved with food under these schedules, suggesting that common mechanisms may underlie the control of cocaine- and food-maintained behavior.     

Additional free reinforcers increase persistence of problem behavior in a clinical context: A partial replication of laboratory findings

Behavioral momentum theory is a quantitative framework used to characterize the persistence of behavior during response disruptors as a function of baseline stimulus–reinforcer relations. Results of several investigations have shown that alternative reinforcement can increase the resistance to change of a target response during extinction. In the present study, concomitant variable‐interval fixed‐time schedules of reinforcement for problem behavior were employed to simulate naturalistic situations involving the superimposition of response‐independent reinforcers on a baseline schedule of reinforcement for problem behavior, as in the common use of noncontingent reinforcement treatments. Resistance to change of problem behavior was assessed during postsession periods of extinction by comparing response rates in extinction following sessions with and without additional reinforcer deliveries arranged by fixed‐time schedules. For 2 out of 3 participants, problem behavior tended to be more resistant to extinction following periods in which additional fixed‐time reinforcers were delivered. These results are discussed in terms of potential effects of noncontingent reinforcement on problem behavior when the intervention is discontinued or implemented without good treatment integrity.     

Delivering alternative reinforcement in a distinct context reduces its counter‐therapeutic effects on relapse

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.     

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.     

Effects of adjusting DRO schedules on the reduction of stereotypic vocalizations in children with autism

The reduction of stereotypic behavior is important for individuals with developmental disabilities because it may interfere with learning new skills. A common procedure used to reduce stereotypic behavior is differential reinforcement of other behavior (DRO). A DRO schedule is a procedure in which reinforcement is delivered given the absence of a target response for a period of time. Although DRO schedules have been shown to be effective in reducing a variety of stereotypic behavior, empirical studies have not yet determined the most effective way to thin the reinforcement schedule. The current study examined the extent to which the relationship between the inter‐response time (IRT) and the DRO requirement affects the reduction of stereotypic behavior. Results of the current study showed the DRO requirement that was set to the 25th percentile of the IRT distribution was more effective in reducing stereotypic behavior when compared with a DRO requirement set to the 95th percentile of the IRT distribution. Copyright © 2009 John Wiley & Sons, Ltd.     

RESPONDING MAINTAINED BY INTERMITTENT REINFORCEMENT: IMPLICATIONS FOR THE USE OF EXTINCTION WITH PROBLEM BEHAVIOR IN CLINICAL SETTINGS

Results of basic research have demonstrated that behavior maintained on an intermittent schedule of reinforcement (INT) will be extinguished more slowly than behavior maintained on a continuous schedule (CRF). Although these findings suggest that problem behaviors may be difficult to treat with extinction if they have been maintained on INT rather than on CRF schedules, few applied studies have examined this phenomenon with human behavior in clinical settings. The purpose of this study was to determine whether problem behavior maintained on CRF schedules would be extinguished more rapidly than behavior maintained on INT schedules. Three individuals diagnosed with profound mental retardation participated after results of pretreatment functional analyses had identified the sources of reinforcement that were maintaining their self-injury, aggression, or disruption. Subjects were exposed to extinction following baseline conditions with CRF or INT schedules alternated within reversal or multielement designs. Results suggested that problem behaviors may not be more difficult to treat with extinction if they have been maintained on INT rather than CRF schedules. However, switching from an INT to a CRF schedule prior to extinction may lower the baseline response rate as well as the total number of responses exhibited during extinction.     

Effects of continuous and intermittent reinforcement for problem behavior during functional communication training

We evaluated the effectiveness of functional communication training (FCT) in reducing problem behavior and in strengthening alternative behavior when FCT was implemented without extinction. Following the completion of functional analyses in which social-positive reinforcement was identified as the maintaining variable for 5 participants' self-injurious behavior (SIB) and aggression, the participants were first exposed to FCT in which both problem behavior and alternative behavior were reinforced continuously (i.e., on fixed-ratio [FR] 1 schedules). During subsequent FCT conditions, the schedule of reinforcement for problem behavior was made more intermittent (e.g., FR 2, FR 3, FR 5, etc.), whereas alternative behavior was always reinforced according to an FR 1 schedule. Results showed that 1 participant's problem behavior decreased and alternative behavior increased during FCT when both behaviors were reinforced on FR 1 schedules. The remaining 4 participants shifted response allocation from problem to alternative behavior as the schedule of reinforcement for problem behavior became more intermittent. These results suggest that individuals might acquire alternative responses during FCT in spite of inconsistencies in the application of extinction, although even small errors in reinforcement may compromise treatment effects.     

COMPARISON OF EXTINCTION,DRO 0-SEC,AND DRO 6-SEC IN THE ELIMINATION OF IMITATIVE RESPONDING UNDER DISCRETE-TRIAL PARADIGMS1

Imitative response levels were observed for normal 5-yr-old children within a discrete-trial imitation paradigm. Following imitation training sessions, children were observed under conditions of contingent reinforcement for three experimental sessions. Following the contingent reinforcement phase, children were then observed under reversal conditions for four sessions. A 3 × 4 repeated measures design was employed for observing response decrements under conditions of extinction, DRO 6-sec, and DRO 0-sec. The DRO 0-sec group demonstrated a significantly greater decrement in imitative responding than did the DRO 6-sec and extinction group. The differences in effects between the two DRO conditions and results from previous studies in which DRO procedures have had little effect in reducing imitative responding, suggest an incomplete understanding of the ways in which DRO procedures may operate.     

Evaluating the role of contingency in differentially reinforced tic suppression

The current study evaluated the effects of tokens delivered on differential reinforcement of zero-rate behavior (DRO) schedules or noncontingently on tic suppression in 4 children with tics. Tic frequency was lower in 3 of 4 children when tokens were delivered contingent on the absence of tics than when tokens were delivered noncontingently.     

AN EVALUATION OF RESURGENCE DURING TREATMENT WITH FUNCTIONAL COMMUNICATION TRAINING

Extinction‐induced resurgence is the recurrence of previously reinforced behavior when another behavior is placed on extinction (Lieving, Hagopian, Long, & O'Connor, 2004). This phenomenon may account for some instances of treatment relapse when problem behavior recovers during extinction‐based treatments. The current study sought to determine whether resurgence of problem behavior would reliably occur with 5 participants who received treatment with FCT. Results showed that problem behavior reemerged for all but 1 participant when the communicative response was exposed to extinction or thin schedules of reinforcement. These findings suggest that resurgence may account for some instances of response recovery during treatment, and that the described procedure may be useful for the further study of resurgence and eventual prevention of this phenomenon.     

Concurrent reinforcement schedules: behavior change and maintenance without extinction

We evaluated the effects of concurrent schedules of reinforcement on negatively reinforced problem behavior and task completion with 3 children with autism. Results indicated that problem behavior occurred at high levels and relatively few tasks were completed when problem behavior produced a break (from tasks) and task completion produced either no consequence or a break. By contrast, problem behavior was eliminated and tasks were completed when problem behavior produced a break and task completion produced a break with access to preferred activities. Treatment gains were maintained without the use of extinction when the response requirement was increased and the schedule of reinforcement was thinned.