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In concurrent schedules, reinforcers are often followed by a brief period of heightened preference for the just‐productive alternative. Such ‘preference pulses’ may reflect local effects of reinforcers on choice. However, similar pulses may occur after nonreinforced responses, suggesting that pulses after reinforcers are partly unrelated to reinforcer effects. McLean, Grace, Pitts, and Hughes (2014) recommended subtracting preference pulses after responses from preference pulses after reinforcers, to construct residual pulses that represent only reinforcer effects. Thus, a reanalysis of existing choice data is necessary to determine whether changes in choice after reinforcers in previous experiments were actually related to reinforcers. In the present paper, we reanalyzed data from choice experiments in which reinforcers served different functions. We compared local choice, mean visit length, and visit‐length distributions after reinforcers and after nonreinforced responses. Our reanalysis demonstrated the utility of McLean et al.'s preference‐pulse correction for determining the effects of reinforcers on choice. However, visit analyses revealed that residual pulses may not accurately represent reinforcer effects, and reinforcer effects were clearer in visit analyses than in local‐choice analyses. The best way to determine the effects of reinforcers on choice may be to conduct visit analyses in addition to local‐choice analyses.
In a frequently used suboptimal‐choice procedure pigeons choose between an alternative that delivers three food pellets with p = 1.0 and an alternative that delivers ten pellets with p = 0.2. Because pigeons reliably choose the probabilistic (suboptimal) alternative, the procedure has been proposed as a nonhuman analog of human gambling. The present experiments were conducted to evaluate two potential threats to the validity of this procedure. Experiments 1 and 2 evaluated if pigeons obtained food at a lower unit price (i.e., pecks per pellet) on the suboptimal alternative than on the optimal alternative. When pigeons worked under this suboptimal procedure they all preferred the suboptimal alternative despite some pigeons paying a higher price for food on that alternative. In Experiment 2, when the unit price ratio more closely approximated the inverse of the expected value ratio, pigeons continued to prefer the suboptimal alternative despite its economic suboptimality. Experiment 3 evaluated if, in accord with the string‐theory of gambling, the valuation of the suboptimal alternative was increased when pigeons misattributed a subset of the suboptimal no‐food trials to the optimal alternative. When trial sequences were arranged to minimize these possible attribution errors, pigeons still preferred the suboptimal alternative. These data remove two threats to the validity of the suboptimal choice procedure; threats that would have suggested that suboptimal choice reflects economic maximization.
The present study evaluated the effects of instructive feedback embedded within a group discrete trial teaching to teach tact relations to nine children diagnosed with autism spectrum disorder using a nonconcurrent multiple‐baseline design. Dependent variables included correct responses for: primary targets (directly taught), secondary targets (taught via instructive feedback), primary observational targets (directly taught to other members of the group), and secondary observational targets (taught via instructive feedback provided to other members of the group). Results showed that all nine participants reached the mastery criterion for the primary targets, as well as acquired the secondary and observational targets without direct teaching. Clinical implications and areas for future research are provided.
Deposit contracting may reduce costs and increase efficacy in contingency management interventions. We evaluated two Internet‐based deposit contract arrangements for smoking. In Experiment 1, nine participants deposited self‐selected amounts that could be earned back for meeting goals. During treatment, participants were reimbursed for breath samples with less than or equal to 6 parts per million carbon monoxide and met the criterion for 47% of samples compared to 1% during baseline. In Experiment 2, 10 participants’ deposits were matched up to $50. No samples met the criterion during baseline but 41.5% met it during treatment. The average deposit was $82 in Experiment 1 and $49 in Experiment 2. Participants rated the intervention favorably and sample submission rates were high. These experiments suggest that Internet‐based self‐tailored deposits are acceptable, feasible, and can promote brief reduction and abstinence in some smokers. Future research should investigate individual and intervention factors that affect long‐term cessation and uptake of deposit contracts.
Hanley, Jin, Vanselow, and Hanratty (2014) described a functional analysis ( FA ) format that relied on a synthesis of multiple contingencies described by caregivers during open‐ended interviews. These interview‐informed synthesized contingency analyses ( IISCA ) provided effective baselines from which to develop socially validated treatments, but the synthesis precluded a precise understanding of individual contingencies influencing problem behavior. We conducted IISCAs and standard FAs (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) for nine children with autism to evaluate the likelihood of differentiation given a number of synthesized versus isolated variables. The IISCA was differentiated for all. The standard FA was differentiated for four; this number increased to six when we included precursors in the standard FA . We then compared treatments based on sets of differentiated analyses for four children. Treatment based on the IISCA was effective for all four; treatments based on the standard FA were effective for two. The role of synthesis in analysis is discussed.
Noncontingent reinforcement is a commonly used procedure to decrease levels of problem behavior. Goals of this intervention are to decrease motivation, responding, and the functional relation between behavior and consequences, but it could also possibly compete with performance of alternative desirable responses. In the current study, we assessed the effects of noncontingent reinforcement arranged from 0% to 100% of sessions on performance of alternative responding across two experiments. Experiment 1 assessed manding (i.e., requests) maintained by attention and tangibles with a child with developmental disabilities and Experiment 2 assessed keypecking maintained by food with six pigeons. We extended previous research by (a) showing that noncontingent reinforcement competes with both the acquisition and maintenance (performance) of an alternative response, (b) extending the generality of the findings across nonhuman and human participants, and (c) eliminating influence of sequence effects through random manipulations of noncontingent value in pigeons. Overall, greater amounts of noncontingent reinforcement competed with both acquisition and maintenance of alternative responding.
Noncontingent reinforcement ( NCR ) is a commonly used treatment for severe problem behavior displayed by individuals with intellectual and developmental disabilities. The current study sought to extend the literature by reporting outcomes achieved with 27 consecutive applications of NCR as the primary treatment for severe problem behavior. All applications of NCR were included regardless of treatment outcome to minimize selection bias favoring successful cases. Participants ranged in age from 5 to 33 years. We analyzed the results across behavioral function and with regard to the use of functional versus alternative reinforcers. NCR effectively treated problem behavior maintained by social reinforcement in 14 of 15 applications, using either the functional reinforcer or alternative reinforcers. When we implemented NCR to treat problem behavior maintained by automatic reinforcement, we often had to add other treatment components to produce clinically significant effects (five of nine applications). Results provide information on the effectiveness and limitations of NCR as treatment for severe problem behavior.
Impairment in social skills is a primary feature of Autism Spectrum Disorders (ASDs). Research indicates that social skills are intimately tied to social development and negative social consequences can persist if specific social behaviors are not acquired. The present study evaluated the effects of behavioral skills training (BST) on teaching four parents of children with ASDs to be social skills trainers. A nonconcurrent multiple baseline design across parent–child dyads was employed and direct observation was used to assess parent and child behaviors Results demonstrated substantial improvement in social skills teaching for all participants for trained and untrained skills. Ancillary measures of child performance indicated improvement in skills as well. High levels of correct teaching responses were maintained at a 1 month follow‐up. This study extends current literature on BST while also providing a helpful, low‐effort strategy to modify how parents can work with their children to improve their social skills.
Noncontingent reinforcement ( NCR ) is typically implemented with extinction ( EXT ) for destructive behavior reinforced by social consequences and without EXT for destructive behavior reinforced by sensory consequences. Behavioral momentum theory ( BMT ) predicts that responding will be more persistent, and treatment relapse in the form of response resurgence more likely, when NCR is implemented without EXT due to the greater overall rate of reinforcement associated with this intervention. We used an analogue arrangement to test these predictions of BMT by comparing NCR implemented with and without EXT . For two of three participants, we observed more immediate reductions in responding during NCR without EXT . However, for all participants, NCR without EXT produced greater resurgence than NCR with EXT when we discontinued all reinforcers during an EXT Only phase, although there was variability in response patterns across and within participants. Implications for treatment of destructive behavior using NCR are discussed.
This study examined the interactions of stimulus type (high‐ vs. low‐tech) and magnitude (duration of access) on preference and reinforcer efficacy. Two preference assessments were conducted to identify highly preferred high‐tech and low‐tech items for each participant. A subsequent assessment examined preference for those items when provided at 30‐s and 600‐s durations. We then evaluated reinforcer efficacy for those same items when provided for a range of durations using progressive‐ratio schedules. Results suggested item type and access duration interacted to influence preference and reinforcer efficacy. Participants preferred high‐tech items at longer durations of access and engaged in more responding when the high‐tech item was provided for long durations, but these patterns were reversed for the low‐tech item. In addition, participants engaged in less responding when the high‐tech item was provided for short durations and when the low‐tech item was provided for long durations.