Approaches for Treating Multiply Controlled Problem Behavior

A portion of problem behavior is maintained by multiple reinforcement contingencies. Treating multiply controlled problem behavior may be more complex than treating problem behavior maintained by a single contingency. Several approaches for addressing multiply controlled problem behavior have been described in the literature. The purpose of this review is to provide practitioners with an overview of function-based approaches for addressing multiply controlled problem behavior. In particular, we present guidelines for functional analysis and treatment. We also describe strengths and limitations of published treatment approaches and discuss strategies for mitigating these limitations. Finally, we describe areas for future research.

Sample-comparison mapping and joint stimulus control

A matching-to-sample task with a 3-sample, 2-comparison mapping has been found to engender joint control by the stimuli that signaled the samples (keylight) and the inter-trial interval (houselight), with a trade-off in the degree of control exerted by each stimulus. To learn about the boundary conditions for the establishment of that joint stimulus control, we trained pigeons in a similar task, but featuring a one-to-one sample-comparison mapping, with two samples and two comparisons. To assess their relative influences, we ran two tests where each of the stimuli was removed: in one test, no sample keylight was presented, and in the other, the ITI was spent in darkness. Results were consistent with both stimuli influencing choice but there was no clear evidence of a trade-off between them. These results suggest that sample-comparison mapping and/or total number of samples may influence how an animal directs its attention to the stimuli available.

Shifts in stimulus control over opioid use with increasing periods of recovery

BACKGROUND

Periods of engaging in an alternative behavior diminishes behavioral control by stimuli occasioning alcohol use. This increase in relapse resistance with increasing recovery suggests that changing stimulus control over substance use may be a mechanism responsible for decreased relapse rates with longer recovery. However, the generality of this phenomenon to other drugs of abuse, including opioid self-administration, remains unclear. This study tests the generality of these findings with etonitazene to determine whether the shift in attention represents a behavioral process that generalizes from conditions we previously reported.

METHODS

Five adult male Lewis rats were trained to respond on levers under two stimulus conditions; high-cost food (food FR150 and etonitazene FR5) and low-cost food (both food and etonitazene FR 5). Next, only the high-cost food stimulus (occasioning etonitazene responding) was presented for 20 sessions (Use Phase) followed by 9 sessions in which only the low-cost food stimulus (occasioning food responding) was presented (Recovery Phase). During the Recovery Phase, testing occurred during the first component of sessions 0, 1, 2, 4, and 8 when rats were re-exposed to the high-cost food stimulus. The number of food responses prior to completing the etonitazene response requirement during this stimulus exposure was the primary measure.

RESULTS

Food responses during stimulus re-exposure increased significantly as a function of recovery sessions completed with a slope [95 % CI] of 2.49 responses/recovery session [0.16, 4.81]. The average number of etonitazene deliveries per use session was 32 ± 6.6 or an average daily dose of 48.8 ± 10.1 μg/kg. During Recovery Phase, etonitazene deliveries decreased to 2.4 ± 1 or 3.6 ± 1.5 μg/kg.

CONCLUSION

The decrease in stimulus control observed for ethanol self-administration appears to generalize to opioid self-administration, indicating this change in stimulus control may play a general role in recovery.

Intraverbal Assessment for Persons with Aphasia or Other Acquired Brain Injury

An intraverbal assessment was administered to older adults with aphasia, using a hierarchy of questions that required increasingly complex verbal discriminative stimulus control. Five categories of errors were defined and analyzed for putative stimulus control, with the aim to identify requisite assessment components leading to more efficient and effective treatments. Evocative control over intraverbal error responses was evident throughout the database, as shown by commonalities within four distinct categories of errors; a fifth category, representing a narrow majority of errors, was less clear in terms of functional control over responses. Generally, questions requiring increasingly complex intraverbal stimulus control resulted in weaker verbal performance for those with aphasia. A new 9-point intraverbal assessment model is proposed, based on Skinner's functional analysis of verbal behavior. The study underscores that loss or disruption of a formerly sophisticated language repertoire presents differently than the fledgling language skills and errors of new learners, such as typically developing children and those with autism or developmental disabilities. Thus, we would do well to consider that rehabilitation may require a different approach to intervention than habilitation. We offer several thematic topics for future research in this area.

The Problem of Class Breakdown in Sidman's (1994, 2000) Theory about the Origin of Stimulus Equivalence

Sidman (1994, 2000) hypothesized that equivalence relations are a direct outcome of reinforcement contingencies. This theory is problematic because contingencies do not always result in equivalence. Sidman proposed that equivalence relations may conflict with analytic units, the other outcome of contingencies (e.g., in conditional discriminations with common responses/reinforcers). This conflict may result in a generalized class breakdown and a failure to pass equivalence tests. This is more likely in nonhumans, very young humans, etc. The conflict can also result in a selective class breakdown and success in equivalence tests. This occurs after experience shows the organism the necessity and utility of this process. The nature of that experience and the class breakdown processes were not described by Sidman. I explored the implications of the following hypotheses for Sidman's theory. First, conditional discriminations with a common response/reinforcer result in a generalized class breakdown when participants fail to discriminate emergent relations incompatible with contingencies from those compatible. Second, learning to discriminate between the two requires a history of multiple exemplar training (MET). This implies that equivalence class breakdown is a common response to exemplars that have nothing in common except their relations. This, however, contradicts Sidman's views about the impossibility of such process in the absence of a complex verbal repertoire. If that type of learning from MET is possible, then the possibility that MET results in the selective formation of equivalence classes must be admitted, and the utility of hypothesizing that equivalence is a direct outcome of reinforcement contingencies can be questioned.

Referent-Based Instruction to Strengthen the Verbal Behavior of Early Learners with Autism and Related Language Disorders

The current study evaluated the use of precision teaching to address the verbal behavior deficits of children with autism and other language disorders. From 2013 to 2018, a high-research-activity doctoral university in the south-central United States operated a free clinic that provided applied behavior anlaysis services to early learners in the local community. Participants received referent-based verbal behavior instruction to strengthen their functional language skills by systematically transferring stimulus control across 4 primary verbal operants: mands, echoics, tacts, and sequelics. Referent-based instruction is premised on the notion that proportionate levels of strength among these 4 operants provide the relational flexibility of naturalistic speaking observed in typical language development. This article details the language gains made by 49 participants who received 13 weeks of intervention for 90 min a day, 4 days a week. Relative strengths and weaknesses were identified in the verbal repertoire of each participant, and individualized fluency aims were subsequently developed. Results of pretest and posttest comparisons show that there was a large effect size within the verbal behavior gains of participants who received precision teaching. Implications for implementing referent-based instruction, as well as future areas of research, are discussed.

The Effects of a Procedure to Decrease Motor Stereotypy on Social Interactions in a Child With Autism Spectrum Disorder

Repetitive and stereotypic motor movements and vocal behavior are among the diagnostic characteristics of autism spectrum disorder (American Psychiatric Association, 2013, Diagnostic and Statistical Manual of Mental Disorders [5th ed.]. Washington, DC: Author). Motor stereotypy can interfere with the acquisition and demonstration of many adaptive skills and may socially stigmatize individuals, limiting the development and maintenance of peer relationships. The current study evaluated the effects of a differential reinforcement procedure used to establish discriminative stimulus control over the rate of motor stereotypy. In the second experimental phase, the child was taught a multistep self-management program using the differential reinforcement procedure. The data indicate that the procedure was effective in decreasing the rate of motor stereotypy across all evaluated settings for an increased duration. Although motor stereotypy was not completely eliminated by the procedure, a large reduction in rate was observed, as well as a large increase in the initiation of and response to social interactions. The findings are discussed in terms of social validity and the establishment and transfer of stimulus control.

Examining the Collateral Effects of Reducing Voice Level on Vocal Stereotypy and Functional Speech

The current study examined the collateral effects of an antecedent intervention for decreasing speech volume on vocal stereotypy. After teaching the participant to use a conversational voice level by providing visual feedback from a decibel meter app, conversational voice levels were differentially reinforced in the presence of a green card. Differential effects in voice magnitude during a green-card condition and a no-card condition were demonstrated using an alternating-treatments design. Results showed a decrease in volume of speech during the green-card condition, an overall decrease in vocal stereotypy, and a decrease to zero levels in loud stereotypical vocalizations. The implications of these findings on the treatment of vocal stereotypy are discussed.

Stimulus Control Research and Practice: Considerations of Stimulus Disparity and Salience for Discrimination Training

Stimulus control plays a prominent role in behavior-analytic service delivery, as many discrimination skills are necessary for daily interactions. Clarification and standardization of terminology are necessary for the advancement of research and practice on stimulus control. The purpose of the present article is to provide an overview of stimulus control and discrimination training as they relate to the disparity and salience of stimuli. An overview and examples of stimulus disparity and stimulus salience are provided, followed by recommendations for efficacious service delivery.

Attentional bias induced by stimulus control (ABC) impairs measures of the approximate number system

Pervasive congruency effects characterize approximate number discrimination tasks. Performance is better on congruent (the more numerous stimulus consists of objects of larger size that occupy a larger area) than on incongruent (where the opposite holds) items. The congruency effects typically occur when controlling for nonnumeric variables such as cumulative area. Furthermore, only performance on incongruent stimuli seems to predict math abilities. Here, we present evidence for an attentional-bias induced by stimulus control (ABC) where preattentive features such as item size reflexively influence decisions, which can explain these congruency effects. In three experiments, we tested predictions derived from the ABC. In Experiment 1, as predicted, we found that manipulation of size introduced congruency effects and eliminated the correlation with math ability for congruent items. However, performance on incongruent items and neutral, nonmanipulated items were still predictive of math ability. A negative correlation between performance on congruent and incongruent items even indicated that they measure different underlying constructs. Experiment 2 demonstrated, in line with the ABC account, that increasing presentation time reduced congruency effects. By directly measuring overt attention using eye-tracking, Experiment 3 revealed that people direct their first gaze toward the array with items of larger individual size, biasing them towards these arrays. The ABC explains why the relation between performance on approximate number discrimination tasks and math achievement has been fragile and suggests that stimulus control manipulations have contaminated the results. We discuss the importance of using stimuli that are representative of the environment.

An Evaluation of Two Tact-Training Procedures on Acquired Tacts and Tacting During Play

A common practice in tact training is to include a supplemental verbal stimulus (e.g., "What is it?") in addition to the presentation of a nonverbal discriminative stimulus. Previous literature has suggested that this supplemental verbal stimulus can impede acquisition and generalization relative to the presentation of the object alone, as it may establish faulty stimulus control or decrease spontaneous tacting. Research has yet to compare these 2 training methods on the generalization of learned tacts to more naturalistic, play-based environments. The present study evaluated the use of "What is it?" compared to the presentation of only the nonverbal discriminative stimulus on tact acquisition among 3 children with autism spectrum disorder and the extent to which these training procedures led to tacting in a play-based setting following discrete-trial training. Overall, participants learned to tact stimuli under both conditions, and all participants demonstrated generalization of tacts in a play-based setting. Recommendations for the development and evaluation of naturalistic posttraining assessment are discussed.

Body Mass Index and stimulus control: Results from a real-world study of eating behaviour

BACKGROUND

Evidence suggests decisions about when, what, and how much to eat can be influenced by external (location, food outlet presence, food availability) and internal (affect) cues. Although the relationship between stimulus control and obesity is debated, it is suggested that individuals with higher BMIs are more driven by cues to eating than individuals in the healthy-weight range (HWR). This study investigates the influence of stimulus control on real-world food intake, and whether stimulus control differs by BMI. It was hypothesised that, compared to those in the HWR, eating among individuals with higher BMIs would be under greater stimulus control.

METHOD

74 participants (n = 34 BMI < 24.9, n = 40 BMI > 24.9) recorded food intake for 14 days using Ecological Momentary Assessment. Participants also responded to 4-5 randomly-timed assessments per day. Known external and internal eating cues were assessed during both assessment types. Within-person logistic regression analyses were used to predict eating vs. non-eating occasions from stimulus control domains.

FINDINGS

Results support the hypothesis that eating was influenced by stimulus control: food availability, affect, time of day, and location significantly distinguished between eating and non-eating instances (AUC-ROC = 0.56-0.69, all p's < 0.001). The presence of food outlets was significantly better at distinguishing between eating and non-eating instances for those with higher BMIs (compared to individuals in the HWR).

DISCUSSION

Results support the notion of stimulus control in shaping eating decisions. Differences in levels of stimulus control between participants in the HWR compared to those with a high BMI suggest that dietary improvement interventions may be more effective when they are tailored to the individual and consider environmental influences on eating behaviour.

Generalizing from the Past, Choosing the Future

Behavior in the present depends critically on experience in similar environments in the past. Such past experience may be important in controlling behavior not because it determines the strength of a behavior, but because it allows the structure of the current environment to be detected and used. We explore a prospective-control approach to understanding simple behavior. Under this approach, order in the environment allows even simple organisms to use their personal past to respond according to the likely future. The predicted future controls behavior, and past experience forms the building blocks of the predicted future. We explore how generalization affects the use of past experience to predict and respond to the future. First, we consider how generalization across various dimensions of an event determines the degree to which the structure of the environment exerts control over behavior. Next, we explore generalization from the past to the present as the method of deciding when, where, and what to do. This prospective-control approach is measurable and testable; it builds predictions from events that have already occurred, and assumes no agency. Under this prospective-control approach, generalization is fundamental to understanding both adaptive and maladaptive behavior.

Signaled reinforcement: Effects of signal reliability on choice between signaled and unsignaled alternatives

When reinforcer availability on one alternative of a concurrent schedule is signaled by a discriminative stimulus, responding on that alternative decreases. We investigated how the correlation between signal presentation and reinforcement (signal reliability) affects choice between signaled and unsignaled alternatives. Six pigeons responded in a concurrent schedule, in which reinforcers on one alternative were signaled by a key-color change. Across conditions, the probability of reinforcement following signal presentation varied (the probability in its absence was the complement). As signal reliability increased, response rates and latencies following signal onset on the signaled alternative decreased, whereas responding on the unsignaled alternative remained unchanged. Because the signal did not alter overall reinforcer rates, these findings are consistent with matching theories and research suggesting that responding on one alternative of a concurrent schedule depends on reinforcer, but not response, rates on other alternatives. However, these findings are inconsistent with others demonstrating concomitant changes in responding on signaled and unsignaled alternatives. We consider whether a response-competition account of concurrent performance can explain these discrepancies, and suggest avenues for future studies to investigate the mechanisms underlying effects of signaled reinforcement in concurrent schedules.

Temporal regularity and stimulus control in multiple fixed interval schedules

In multiple fixed interval schedules of reinforcement, different time intervals are signaled by different environmental stimuli which acquire control over behavior. Previous work has shown that temporal performance is controlled not only by external stimuli but also by temporal aspects of the task, depending on the order in which the different intervals are trained - intermixed across trials or in blocks of several trials. The aim of this study was to further describe the training conditions under which the stimuli acquire control over temporal performance. We manipulated the number of consecutive trials of each fixed interval (FI) per training block (Experiment I) and the number of FIs trained (Experiment II). The results suggest that when trained in blocks of several consecutive trials of the same FI, temporal performance is controlled by temporal regularities across trials and not by the visual stimuli that signal the FIs. One possible account for those data is that the temporal cues overshadow the visual stimuli for the control of temporal performance. Similar results have also been observed with humans, which suggest that temporal regularity overcomes the stimuli in the control of behavior in temporal tasks across species.

Evaluating the Effects of Similar and Distinct Discriminative Stimuli During Auditory Conditional Discrimination Training With Children With Autism

Children with autism are often taught auditory conditional discriminations in the form of personal information questions that might prove useful in conversation (e.g., "What is your favorite food?" "Pizza" and "What is your favorite color?" "Purple"). In these questions, the auditory stimuli presented as part of the compound discriminative stimulus (i.e., what, favorite, color/food) do not always simultaneously control responding. If all components of the auditory stimulus do not control responding, a child may master 1 target but have trouble acquiring subsequent targets that have a component of a previously learned auditory stimulus because the previously learned response is emitted. One way to avoid this problem is to teach many targets that have no overlapping component stimuli before introducing targets that include a previously learned component. Another way to avoid the problem is to systematically introduce overlapping stimulus components simultaneously to facilitate control by all relevant components. Three children with autism were taught auditory conditional discriminations. An adapted alternating-treatments design was used to compare the use of training sets with programmed overlap of component auditory stimuli to training sets with no overlap of stimulus components. The effects of these 2 arrangements were evaluated on trials to criterion and percentage accuracy during acquisition. All participants reached mastery faster with at least 1 target set in the nonoverlap condition compared to the overlapping condition; 2 out of the 3 participants met the mastery criteria for both overlapping and nonoverlapping targets at a similar rate by the 3rd training set.

Delivering Cognitive Behavioral Therapy for Insomnia in the Real World: Considerations and Controversies

Cognitive-behavioral therapy for insomnia (CBT-I) has emerged as the first-line treatment for chronic insomnia but remains massively underused relative to the prevalence of insomnia disorder. This article focuses on 3 key issues in the delivery of CBT-I in the real world. First, where and how should CBT-I be delivered and who should deliver it? Second, who is an appropriate candidate for CBT-I? Third, how do you measure quality care with CBT-I? These issues give rise to targets for future research aimed at improving the implementation science of CBT-I in the real world.

Utilizing Group-Based Contingencies to Increase Hand Washing in a Large Human Service Setting

Hand washing is the most important preventative measure for the reduction of contagious disease. Although hand washing is easy to perform, non-adherence is a ubiquitous problem. Several studies have demonstrated the effectiveness of multi-component intervention packages to improve hand washing among employees; however, interventions are limited to acute settings, are often implemented for a short period of time, and rarely, if ever, include information on long-term effectiveness. The purpose of the current study was to utilize a behavior analytic approach to determine the stimulus conditions under which hand washing should occur, and to assess and then implement a long-term monitoring system among direct care workers in a large, non-acute inpatient unit. A single-case repeated measures reversal design was used to evaluate the effectiveness of two interventions aimed at improving hand washing adherence. A lottery was found to be effective in increasing hand hygiene for 2-years with 170 staff.

Multiple control responses and resurgence of human behavior

Behavior that was previously extinguished may reoccur, or resurge, when an alternative response contacts extinction or when reinforcement conditions worsen. Researchers have studied resurgence of human responding in laboratory settings with procedures commonly used with nonhumans. In contrast to nonhuman responding, researchers have failed to observe resurgence of the target response at rates that differ from an inactive control response with verbally competent humans. But this may have been the result of using a single control response. The current study examined this possibility by randomly allocating participants (N = 20) to a condition with either two or four control responses. When the alternative response contacted extinction, having more control responses did not reduce overall responding to control options, and aggregated responding to control options were similar to target response rates. Interestingly, most participants responded more to one control response over all other control responses when the alternative response contacted extinction. This study provides additional support for previous research that finds consistent differences between human and nonhuman responding during resurgence procedures. Two potential reasons for variability in human responding during resurgence tests include less time in experimental sessions and the influence of verbal behavior.

Environment tracking and signal following in a reinforcer-ratio reversal procedure

Several studies suggest that the degree of control by reinforcer ratios (environment tracking) and by exteroceptive stimuli that signal future reinforcer availability (signal following) depends on environmental certainty: As reinforcers become more likely at one location, environmental contingencies exert stronger control and exteroceptive stimuli exert weaker control. This research has not yet been extended to environments in which reinforcer availability changes across time, even though such changes are present in most natural environments. Thus, in the present experiment, we examined environment tracking and signal following in a concurrent schedule in which the reinforcer ratio reversed to its reciprocal 30 s after a reinforcer delivery and keylight-color stimuli signaled the likely or definite time or location of the next reinforcer. Across conditions, we manipulated environmental certainty by varying the probability of reinforcer deliveries on the locally richer key. This made the location of future reinforcers at a particular time more or less certain, but did not change the overall reinforcer ratio. Changes in local environmental certainty had little to no effect on environment tracking and signal following; in all conditions, keylight-color stimuli strongly controlled choice and reinforcer ratios exerted weak control. The present findings suggest that the extent of environment tracking and signal following is primarily determined by global, not local, environmental certainty.

Sample First versus Comparison First Stimulus Presentations: Preliminary Findings for Two Individuals with Autism

The current study was a replication of Petursdottir and Aguilar (Journal of Applied Behavior Analysis, 46, 58-68, 2016). Two different stimulus presentations were evaluated during auditory-visual discrimination training. A sample-first procedure, in which the sample stimulus was presented before the comparison stimuli, was compared to a comparison-first procedure, in which the sample presentation was presented after the comparison stimuli. The results indicated that both participants learned more quickly in the comparison-first condition, a finding that differed from Petursdottir and Aguilar (Journal of Applied Behavior Analysis, 46, 58-68, 2016).

Generalization of response patterns in a multiple peak procedure

Stimulus generalization is typically assessed by analyzing overall response rates. Studies of generalization of response-rate patterns across time are less common, despite the ubiquitous nature of time and the strong temporal control over behavior in the natural world. Thus, we investigated generalization of response-rate patterns across time using a multiple peak procedure in pigeons. The frequency (fast or slow) at which the color of a keylight changed signaled a fixed-interval (FI) 5-s or 20-s schedule, counterbalanced across subjects. In peak trials, the frequency of keylight-color changes was varied. For the fast and slow training stimuli, response rates in peak trials were controlled by the arranged FI schedule value; they increased as the arranged reinforcer time approached, and decreased thereafter. Response-rate patterns to all test stimuli were similar to response-rate patterns to the slow training stimulus for all subjects. Thus, overall, strong generalization from the slow training stimulus to all test stimuli was evident, whereas there was little to no generalization from the fast training stimulus. These findings extend past research examining generalization of temporally controlled response-rate patterns, and provide a useful starting point for future investigations of generalization of fixed-interval responding. A thorough understanding of generalization processes requires analysis of dependent variables other than overall response rates, especially when responding is likely to be temporally controlled.

Examining the maintenance and generalization effects of repeated practice: A comparison of three interventions

Repeated reading (RR) procedures are consistent with the procedures recommended by Haring and Eaton's (1978) Instructional Hierarchy (IH) for promoting students' fluent responding to newly learned stimuli. It is therefore not surprising that an extensive body of literature exists, which supports RR as an effective practice for promoting students' reading fluency of practiced passages. Less clear, however, is the extent to which RR helps students read the words practiced in an intervention passage when those same words are presented in a new passage. The current study employed randomized control design procedures to examine the maintenance and generalization effects of three interventions that were designed based upon Haring and Eaton's (1978) IH. Across four days, students either practiced reading (a) the same passage seven times (RR+RR), (b) one passage four times and three passages each once (RR+Guided Wide Reading [GWR]), or (c) seven passages each once (GWR+GWR). Students participated in the study across 2weeks, with intervention being provided on a different passage set each week. All passages practiced within a week, regardless of condition, contained four target low frequency and four high frequency words. Across the 130 students for whom data were analyzed, results indicated that increased opportunities to practice words led to greater maintenance effects when passages were read seven days later but revealed minimal differences across conditions in students' reading of target words presented within a generalization passage.

Headphone screening to facilitate web-based auditory experiments

Psychophysical experiments conducted remotely over the internet permit data collection from large numbers of participants but sacrifice control over sound presentation and therefore are not widely employed in hearing research. To help standardize online sound presentation, we introduce a brief psychophysical test for determining whether online experiment participants are wearing headphones. Listeners judge which of three pure tones is quietest, with one of the tones presented 180° out of phase across the stereo channels. This task is intended to be easy over headphones but difficult over loudspeakers due to phase-cancellation. We validated the test in the lab by testing listeners known to be wearing headphones or listening over loudspeakers. The screening test was effective and efficient, discriminating between the two modes of listening with a small number of trials. When run online, a bimodal distribution of scores was obtained, suggesting that some participants performed the task over loudspeakers despite instructions to use headphones. The ability to detect and screen out these participants mitigates concerns over sound quality for online experiments, a first step toward opening auditory perceptual research to the possibilities afforded by crowdsourcing.

Unraveling sources of stimulus control in a temporal discrimination task

In temporal discriminations tasks, more than one stimulus may function as a time marker. We studied two of them in a matching-to-sample task, the sample keylight and the houselight that signaled the intertrial interval (ITI). One group of pigeons learned a symmetrical matching-to-sample task with two samples (2 s or 18 s of a center keylight) and two comparisons (red and green side keys), whereas another group of pigeons learned an asymmetrical matching-to-sample task with three samples (2 s, 6 s, and 18 s) and two comparisons (red and green). In the asymmetrical task, 6-s and 18-s samples shared the same comparison. In a subsequent retention test, both groups showed a preference for the comparison associated with the longer samples, a result consistent with the hypothesis that pigeons based their choices on the duration elapsed since the offset of the houselight (i.e., sample duration + retention interval). Results from two no-sample tests further corroborated the importance of the ITI illumination as a time marker: When the ITI was illuminated, the proportion of choices correlated positively with the retention interval; when the ITI was darkened, choices fell to random levels. However, the absolute value of choice proportions suggested that the sample stimulus was also a time marker. How multiple stimuli acquire control over behavior and how they combine remains to be worked out.

Algorithmic analysis of relational learning processes in instructional technology: Some implications for basic, translational, and applied research

A few noteworthy exceptions notwithstanding, quantitative analyses of relational learning are most often simple descriptive measures of study outcomes. For example, studies of stimulus equivalence have made much progress using measures such as percentage consistent with equivalence relations, discrimination ratio, and response latency. Although procedures may have ad hoc variations, they remain fairly similar across studies. Comparison studies of training variables that lead to different outcomes are few. Yet to be developed are tools designed specifically for dynamic and/or parametric analyses of relational learning processes. This paper will focus on recent studies to develop (1) quality computer-based programmed instruction for supporting relational learning in children with autism spectrum disorders and intellectual disabilities and (2) formal algorithms that permit ongoing, dynamic assessment of learner performance and procedure changes to optimize instructional efficacy and efficiency. Because these algorithms have a strong basis in evidence and in theories of stimulus control, they may have utility also for basic and translational research. We present an overview of the research program, details of algorithm features, and summary results that illustrate their possible benefits. It also presents arguments that such algorithm development may encourage parametric research, help in integrating new research findings, and support in-depth quantitative analyses of stimulus control processes in relational learning. Such algorithms may also serve to model control of basic behavioral processes that is important to the design of effective programmed instruction for human learners with and without functional disabilities.

A Preliminary Analysis of Procedures to Teach Children with Autism to Report Past Behavior

Deficits in reporting past behavior may have implications for a child's social development and safety. Behavioral interpretations of memory and research on do/say correspondence provide valuable strategies to teach reporting past behavior when deficits are observed. The current study examined procedures to teach accurate reporting of past behavior following a delay for two children diagnosed with autism. During baseline, both participants accurately reported past behavior when immediately probed. Neither participant emitted accurate reporting following a delay during end-of-day probes. Treatment procedures included prompting, reinforcement, and fading procedures designed to maintain stimulus control across the delay. Both participants demonstrated accurate reporting of past behavior on delayed probes, including when conducted by a caregiver.

Joint stimulus control in a temporal discrimination task

The ability to identify stimuli that signal important events is fundamental for an organism to adapt to its environment. In the present paper, we investigated how more than one stimulus could be used jointly to learn a temporal discrimination task. Ten pigeons were exposed to a symbolic matching-to-sample procedure with three durations as samples (2, 6, and 18 s of keylight) and two colors as comparisons (red and green hues). A 30-s intertrial interval (ITI), illuminated with a houselight, separated the trials. Both the houselight and the sample keylight could control responding, so two tests were run to assess how these stimuli influenced choice. In the no-sample test, the keylight was not presented; in the dark-ITI test, the houselight was not illuminated. Results suggest that both houselight and keylight controlled choice, and with the exception of one animal, the more a pigeon relied on one of these stimuli, the less it appeared to rely on the other.

Signalling changes to individuals who show resistance to change can reduce challenging behaviour

BACKGROUND & OBJECTIVES

Several neurodevelopmental disorders are associated with resistance to change and challenging behaviours - including temper outbursts - that ensue following changes to routines, plans or expectations (here, collectively: expectations). Here, a change signalling intervention was tested for proof of concept and potential practical effectiveness.

METHODS

Twelve individuals with Prader-Willi syndrome participated in researcher- and caregiver-led pairing of a distinctive visual-verbal signal with subsequent changes to expectations. Specific expectations for a planned subset of five participants were systematically observed in minimally manipulated natural environments. Nine caregivers completed a temper outburst diary during a four week baseline period and a two week signalling evaluation period.

RESULTS

Participants demonstrated consistently less temper outburst behaviour in the systematic observations when changes imposed to expectations were signalled, compared to when changes were not signalled. Four of the nine participants whose caregivers completed the behaviour diary demonstrated reliable reductions in temper outbursts between baseline and signalling evaluation.

LIMITATIONS

An active control group for the present initial evaluation of the signalling strategy using evidence from caregiver behaviour diaries was outside the scope of the present pilot study. Thus, findings cannot support the clinical efficacy of the present signalling approach.

CONCLUSIONS

Proof of concept evidence that reliable pairing of a distinctive cue with a subsequent change to expectation can reduce associated challenging behaviour is provided. Data provide additional support for the importance of specific practical steps in further evaluations of the change signalling approach.

The effect of the long anchor duration on performance in the temporal bisection procedure

The present study investigated how the value of the long anchor duration influences the bisection point (BP) in the temporal bisection procedure. The ratio similarity rule (Gibbon, 1981, On the form and location of the psychometric bisection function for time. Journal of Mathematical Psychology, 24(1), 58-87) hypothesizes that the location of the BP is determined by a ratio comparison between the short and long anchor durations. The Short/no short hypothesis (Machado and Keen, 2003, Temporal discrimination in a long operant chamber. Behavioural Processes, 62(1), 157-182) indicates that the location of the BP is influenced mainly by the short duration. Two experiments with pigeons manipulated the long anchor duration while fixing the short anchor duration in a series of anchor pairs. The results showed that the location of the BP depended on the initial training condition, a primacy effect. When the initial training condition used anchors of 3- vs. 9-s, a relatively strong influence of the long anchor duration was observed as predicted by the ratio similarity rule. On the other hand, when anchors were 3- vs. 27-s in the initial training condition, the effect of the long duration was relatively small, conforming more closely to the Short/no short hypothesis. Keypecking to the sample key during a trial, sample-cue responding, was also observed. The functions relating sample-cue responding to elapsed trial time also indicated the primacy effect.

Current FDA regulatory guidance on the conduct of drug discrimination studies for NDA review: Does the scientific literature support recent recommendations?

BACKGROUND

The Controlled Substances Staff of the Center for Drug Evaluation and Research at the US Food and Drug Administration and the Pharmaceutical Research Manufacturers Association (PhRMA) conducted a series of open forum dialog sessions between 2006 and 2016. A Cross Company Abuse Liability Council (CCALC) was formed during the process of this unique collaborative effort between Industry and Federal Regulators whose goals were to establish the development of standards for the preclinical screening of new molecular entities for schedule control actions required as part of every New Drug Application process. The draft guidance document was published and disseminated in 2010, which allowed for alternative approaches to each study protocol requirement needed for NDA review, if the approach satisfied the requirements of the applicable statutes and regulations (i.e., the controlled substance act). In a series of recent pre-study protocol reviews requested by confidential Pharmaceutical Sponsors of MPI Research, the CSS staff appeared to change its policy and set forth to require all drug discrimination study data to be generated under "extinction" test sessions. MPI Research is a Contract Research Organization acting on behalf of pharmaceutical companies and bound under separate confidentiality agreements.

PURPOSE

The purpose of this review is to highlight the data appearing in peer-reviewed scientific journals that do not support the regulatory administrative constraints on one specific testing methodology (extinction) to the exclusion of another (reinforced test sessions).

CONCLUSION

This mind shift represents a restrictive administrative policy by the FDA that is not supported by the published data.

Emergence of Intraverbal Responding Following Tact Instruction with Compound Stimuli

Effective intraverbal responding often requires control by multiple elements of a verbal stimulus. The purpose of this study was to examine the emergence of such intraverbal relations following tact instruction with compound stimuli and to analyze any resulting error patterns. Participants were seven typically developing children between 3 and 5 years of age. After being taught to tact four overlapping compound stimuli that differed along color and shape dimensions, participants were tested for emergent intraverbal responding. Three participants performed with high accuracy and four with intermediate accuracy when correct intraverbal responding required control by multiple elements (i.e., color names and shape names) of the verbal stimulus. Five participants performed with high accuracy when intraverbal responding required control by only a single stimulus element, and all participants showed emergence of reverse intraverbal relations when the response required naming only a single stimulus element (i.e., color or shape). There was an insufficient number of errors to perform detailed error analyses at the individual level, but overall, the first element of a verbal stimulus was more likely to exert control over the response than the second element, and color words were more likely to exert control than shape words. Results suggest that individual stimulus elements acquired independent control over the responses that had been established as tacts.

Evaluation of a Blocked-Trials Procedure to Establish Complex Stimulus Control over Intraverbal Responses in Children with Autism

We evaluated the use of a blocked-trials procedure to establish complex stimulus control over intraverbal responses. The participants were four young boys with a diagnosis of autism who had struggled to master intraverbals. The blocked-trials procedures involved presentation of stimuli in separate trial blocks. The trial blocks gradually reduced in size contingent upon correct responding, until the stimuli were presented in quasi-random order. All participants acquired multiple discriminations with the blocked-trials procedure, although additional procedures were needed to teach the first discrimination with two participants. Following acquisition of multiple discriminations, two participants acquired a novel discrimination with quasi-random presentation of stimuli, and a third participant demonstrated discriminated responding in intraverbal probes.

Emergent Intraverbal Forms may Occur as a Result of Listener Training for Children with Autism

The purpose of the present study was to assess whether intraverbal behavior, in the form of answers to questions, emerges as a result of listener training for five children diagnosed with autism. Listener responses were targeted and taught using prompting and differential reinforcement. Following successful acquisition of listener responses, the intraverbal form of the response was probed. Data were evaluated via a nonconcurrent multiple-baseline design that included a control series. Results showed listener-to-intraverbal transfer for four of the five participants. One participant required additional teaching that involved tacting the items selected during listener training.

Reduction of Rapid Eating in an Adolescent Female with Autism

Rapid eating, a potentially dangerous and socially inappropriate behavior, has received relatively little attention in the literature. This study sought to extend the research in this area by further evaluating the effectiveness of a vibrating pager combined with a rule for increasing inter-response time between bites in one adolescent female diagnosed with autism. Results indicated that inter-response time increased from baseline only after a vocal prompt to "wait" was introduced across clinic and home settings. Implications for promoting autonomy in individuals with developmental disabilities are discussed.This antecedent-based intervention can easily be generalized to caregiversThe unobtrusive nature of the intervention allows for implementation in inclusive settingsThere are implications for promoting social skills in naturalistic environmentsThe intervention can promote independence through teaching self-management.

Adventitious Reinforcement of Maladaptive Stimulus Control Interferes with Learning

Persistent error patterns sometimes develop when teaching new discriminations. These patterns can be adventitiously reinforced, especially during long periods of chance-level responding (including baseline). Such behaviors can interfere with learning a new discrimination. They can also disrupt already learned discriminations, if they re-emerge during teaching procedures that generate errors. We present an example of this process. Our goal was to teach a boy with intellectual disabilities to touch one of two shapes on a computer screen (in technical terms, a simple simultaneous discrimination). We used a size-fading procedure. The correct stimulus was at full size, and the incorrect-stimulus size increased in increments of 10 %. Performance was nearly error free up to and including 60 % of full size. In a probe session with the incorrect stimulus at full size, however, accuracy plummeted. Also, a pattern of switching between choices, which apparently had been established in classroom instruction, re-emerged. The switching pattern interfered with already-learned discriminations. Despite having previously mastered a fading step with the incorrect stimulus up to 60 %, we were unable to maintain consistently high accuracy beyond 20 % of full size. We refined the teaching program such that fading was done in smaller steps (5 %), and decisions to "step back" to a smaller incorrect stimulus were made after every 5-instead of 20-trials. Errors were rare, switching behavior stopped, and he mastered the discrimination. This is a practical example of the importance of designing instruction that prevents adventitious reinforcement of maladaptive discriminated response patterns by reducing errors during acquisition.

Accurate Delayed Matching-to-Sample Responding without Rehearsal: An Unintentional Demonstration with Children

Research on joint control has focused on mediational responses, in which simultaneous stimulus control from two sources leads to the emission of a single response, such as choosing a comparison stimulus in delayed matching-to-sample. Most recent studies of joint control examined the role of verbal mediators (i.e., rehearsal) in evoking accurate performance. They suggest that mediation is a necessity for accurate delayed matching-to-sample responding. We designed an experiment to establish covert rehearsal responses in young children. Before participants were taught such responses; however, we observed that they responded accurately at delays of 15 and 30 s without overt rehearsal. These findings suggest that in some cases, rehearsal is not necessary for accurate responding in such tasks.

A model for discriminating reinforcers in time and space

Both the response-reinforcer and stimulus-reinforcer relation are important in discrimination learning; differential responding requires a minimum of two discriminably-different stimuli and two discriminably-different associated contingencies of reinforcement. When elapsed time is a discriminative stimulus for the likely availability of a reinforcer, choice over time may be modeled by an extension of the Davison and Nevin (1999) model that assumes that local choice strictly matches the effective local reinforcer ratio. The effective local reinforcer ratio may differ from the obtained local reinforcer ratio for two reasons: Because the animal inaccurately estimates times associated with obtained reinforcers, and thus incorrectly discriminates the stimulus-reinforcer relation across time; and because of error in discriminating the response-reinforcer relation. In choice-based timing tasks, the two responses are usually highly discriminable, and so the larger contributor to differences between the effective and obtained reinforcer ratio is error in discriminating the stimulus-reinforcer relation. Such error may be modeled either by redistributing the numbers of reinforcers obtained at each time across surrounding times, or by redistributing the ratio of reinforcers obtained at each time in the same way. We assessed the extent to which these two approaches to modeling discrimination of the stimulus-reinforcer relation could account for choice in a range of temporal-discrimination procedures. The version of the model that redistributed numbers of reinforcers accounted for more variance in the data. Further, this version provides an explanation for shifts in the point of subjective equality that occur as a result of changes in the local reinforcer rate. The inclusion of a parameter reflecting error in discriminating the response-reinforcer relation enhanced the ability of each version of the model to describe data. The ability of this class of model to account for a range of data suggests that timing, like other conditional discriminations, is choice under the joint discriminative control of elapsed time and differential reinforcement. Understanding the role of differential reinforcement is therefore critical to understanding control by elapsed time.

Discrete and continuous stimulus control in the A-not-B sandbox task

In behavior-analytic studies of generalization, stimulus control appears to be discrete rather than continuous: after two behavior patterns R1 and R2 are trained in the presence of stimuli A and B, respectively, tests of intermediate stimuli evoke R1 and R2 in varying proportions rather than an actual mix of R1 and R2. By contrast, theories and data from developmental psychology suggest that spatial searches in the A-not-B sandbox task may be continuous: after burying an object at position A and then at position B, children may search the sand surface at positions that are actually intermediate between A and B. The published evidence so far has been ambiguous, however, because researchers typically report group means rather than response distributions, and group means intermediate between A and B might be statistical artefacts of averaging across subjects. Here we report two A-not-B sandbox studies designed to address this issue. In Experiment 1, which employed a purely motor A-not-B procedure, stimulus control was found to be continuous. In Experiment 2, which used a purely observational A-not-B procedure, stimulus control was basically discrete but also exhibited continuous aspects. These findings are discussed in relation to cognitive and behavior-analytic approaches to stimulus control.

Venom-spraying behavior of the scorpion Parabuthus transvaalicus (Arachnida: Buthidae)

Many animals use chemical squirting or spraying behavior as a defensive response. Some members of the scorpion genus Parabuthus (family Buthidae) can spray their venom. We examined the stimulus control and characteristics of venom spraying by Parabuthus transvaalicus to better understand the behavioral context for its use. Venom spraying occurred mostly, but not always, when the metasoma (tail) was contacted (usually grasped by forceps), and was absent during stinging-like thrusts of the metasoma apart from contact. Scorpions were significantly more likely to spray when contact was also accompanied by airborne stimuli. Sprays happened almost instantaneously following grasping by forceps (median=0.23s) as a brief (0.07-0.30s, mean=0.18s), fine stream (<5° arc) that was not directed toward the stimulus source; however, rapid independent movements of the metasoma and/or telson (stinger) often created a more diffuse spray, increasing the possibility of venom contact with the sensitive eyes of potential scorpion predators. Successive venom sprays varied considerably in duration and velocity. Collectively, these results suggest that venom spraying might be useful as an antipredator function and can be modulated based on threat.

Treatment for insomnia in combat-exposed OEF/OIF/OND military veterans: preliminary randomized controlled trial

Chronic insomnia is highly prevalent among military personnel returning from Iraq and Afghanistan. We evaluated the effects of a military version of a brief behavioral treatment of insomnia (BBTI-MV) compared to an information only control (IC) condition in combat-exposed Veterans of Operations Enduring/Iraqi Freedom or Operation New Dawn (OEF/OIF/OND) on insomnia, sleep quality, and daytime symptoms of anxiety and depression. Forty OEF/OIF/OND Veterans (Mean age = 38.4 years old, s.d. = 11.69; 85% men; 77.5% white) were randomized to one of two conditions. BBTI-MV consisted of two in-person sessions and two telephone contacts delivered over four weeks, and included personalized recommendations to reduce insomnia. The IC condition also consisted of 2 in-person sessions two telephone contacts delivered over four weeks, and Veterans were encouraged to read written information about sleep-promoting behaviors. The Insomnia Severity Index, Pittsburgh Sleep Quality Index, PTSD Checklist, and Beck Depression and Anxiety Inventories were completed at baseline, post-treatment, and at the six-month follow-up. Both interventions were associated with clinically significant improvements in insomnia, although the magnitude of improvements in sleep and rates of treatment response and remission were greater for BBTI-MV compared to IC from pre- to post-treatment. Both BBTI-MV and the provision of information were associated with clinically significant improvements in insomnia among Veterans. Despite the preliminary nature of the findings and limitations inherent to small controlled trials, the findings suggest that both approaches may provide viable options in a stepped-care approach to the treatment of insomnia in retuning combat-exposed Veterans. Larger, confirmatory effectiveness trials are required.

CLINICALTRIALSGOV IDENTIFIER

NCT00840255.

Insomnia

Insomnia, as the term is used by patients and in primary care, is a symptom: dissatisfaction with the quality or quantity of sleep obtained, despite attempts. For acute insomnia, reversal of the trigger (if possible) and treatment with safe, effective sleep medication are advised. For chronic insomnia, as with other types of symptoms, trying to distinguish between several potential underlying causes is key, because no single treatment approach is appropriate for all situations. Specific conditions such as restless legs syndrome, circadian rhythm disorders, and sleep apnea have specific treatment approaches.