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We evaluated the effectiveness of a behavioral skills training package to teach implementation of Phases 1, 2, and 3A of the picture exchange communication system (PECS) to teachers employed at a therapeutic center for children with autism. Probes in the natural environment and follow‐up were conducted with children who were assigned to work with the teachers in their own classrooms. Results provide additional support for the efficacy of behavioral skills training to teach implementation of PECS.

We compared 2 variations of differential‐reinforcement‐of‐low‐rate (DRL) procedures: spaced‐responding DRL, in which a reinforcer was delivered contingent on each response if a specified interval had passed since the last response, and full‐session DRL, in which a reinforcer was presented at the end of an interval if the response rate was below criterion within the specified interval. We used a human‐operant procedure and analyzed within‐session responding to assess any similarities or differences between procedures. Data revealed a positive contingency between responding and reinforcement under the spaced‐responding DRL schedule and a negative contingency under the full‐session DRL schedule. Furthermore, 60% of the participants discontinued responding by the last full‐session DRL session. Implications for the appropriate procedural and taxonomical usage of both DRL schedules are discussed.

When the availability of reinforcers depends on time since an event, time functions as a discriminative stimulus. Behavioral control by elapsed time is generally weak, but may be enhanced by added stimuli that act as additional time markers. The present paper assessed the effect of brief and continuous added stimuli on control by time‐based changes in the reinforcer differential, using a procedure in which the local reinforcer ratio reversed at a fixed time after the most recent reinforcer delivery. Local choice was enhanced by the presentation of the brief stimuli, even when the stimulus change signalled only elapsed time, but not the local reinforcer ratio. The effect of the brief stimulus presentations on choice decreased as a function of time since the most recent stimulus change. We compared the ability of several versions of a model of local choice to describe these data. The data were best described by a model which assumed that error in discriminating the local reinforcer ratio arose from imprecise discrimination of reinforcers in both time and space, suggesting that timing behavior is controlled not only by discrimination elapsed time, but by discrimination of the reinforcer differential in time.

We evaluated the effects of behavioral skills training in the home for teaching children with autism to abstain from going with strangers and immediately inform a familiar adult of the stranger's attempt to lure them in the natural environment. All participants learned to respond correctly to lures in the home and demonstrated concomitant changes in untrained natural settings. In situ training and an added incentive were necessary for 1 participant.

The reinforcers that maintain target instrumental responses also reinforce other responses that compete with them for expression. This competition, and its imbalance at points of transition between different schedules of reinforcement, causes behavioral contrast. The imbalance is caused by differences in the rates at which different responses come under the control of component stimuli. A model for this theory of behavioral contrast is constructed by expanding the coupling coefficient of MPR (Killeen, 1994). The coupling coefficient gives the degree of association of a reinforcer with the target response (as opposed to other competing responses). Competing responses, often identified as interim or adjunctive or superstitious behavior, are intrinsic to reinforcement schedules, especially interval schedules. In addition to that base‐rate of competition, additional competing responses may spill over from the prior component, causing initial contrast; and they may be modulated by conditioned reinforcement or punishment from stimuli associated with subsequent component change, causing terminal contrast. A formalization of these hypotheses employed (a) a hysteresis model of off‐target responses giving rise to initial contrast, and (b) a competing traces model of the suppression or enhancement of ongoing competitive responses by signals of following‐schedule transition. The theory was applied to transient contrast, the following schedule effect, and the component duration effect.

Previous research has demonstrated the efficacy of behavioral skills training (BST) and in situ training (IST) for teaching children to protect themselves. However, BST may be resource intensive and difficult to implement on a large scale. We evaluated a computerized version of BST (CBST) to teach safety skills and determined the extent to which safety skills generalized across different dangers. In Study 1, 11 children learned, via CBST and IST, to respond safely when asked to leave with a stranger. In Studies 2 and 3, IST was implemented with 16 children for 1 or 2 dangers after exposure to CBST for 3 dangers. Participants correctly self‐protected from dangers after CBST and IST, and performance generalized to similar dangers for which participants did not receive IST. CBST may be an acceptable substitute for BST when combined with IST to improve efficiency and maintain efficacy in a comprehensive safety skills program.

Behavior that resembles instruction following might sometimes be under stimulus control of extraneous variables. We evaluated the effects of some of these variables (i.e., presence of relevant objects, associations between instructions and object sets) with 3 children with intellectual disabilities. In Experiment 1, we assessed whether subjects were more likely to follow instructions that required object manipulation and whether subjects were more likely to follow these instructions when only relevant objects were present. All subjects were more likely to follow instructions that required object manipulation when only relevant objects were present. In Experiment 2, we evaluated whether instruction following would be less likely if the same object set was associated with multiple instructions, and found this to be the case for 2 of 2 subjects. Findings highlight the need to train instruction following under different conditions to ensure that responding comes under stimulus control of the instructions.

Discrete‐trial instruction (DTI) is a teaching strategy that is often incorporated into early intensive behavioral interventions for children with autism. Researchers have investigated time‐ and cost‐effective methods to train staff to implement DTI, including self‐instruction manuals, video modeling, and interactive computer training (ICT). ICT combines the best components of self‐instruction manuals and video models, and have the same benefits; however, there is limited research on this training method. Therefore, the purpose of this study was to investigate ICT to teach university students to implement DTI with children with autism. All participants' teaching fidelity increased during both role‐plays with an adult and instructional sessions with a child with autism. In addition, participants demonstrated an increase in teaching fidelity with untrained instructional programs. All participants were able to complete training in an average of 2 hr, and social validity ratings were high.

The type of procedure used to measure a target behavior may directly influence the perceived treatment outcomes. In the present study, we examined the influence of different data‐analysis procedures on the outcomes of two commonly used treatments on the vocal stereotypy of 2 children with an autism spectrum disorder. In Study 1, we compared an interrupted and uninterrupted data‐analysis procedure to measure vocal stereotypy during the implementation of response interruption and redirection (RIRD). The results showed that the interrupted data‐analysis procedure overestimated the effectiveness of RIRD. In Study 2, we examined the influence of different data‐analysis procedures on the interpretation of the relative effects of 2 different treatments for vocal stereotypy. Specifically, we compared interrupted and uninterrupted data‐analysis procedures during the implementation of RIRD and noncontingent reinforcement (NCR) as a treatment for vocal stereotypy. The results showed that, as in Study 1, the interrupted data‐analysis procedure overestimated the effectiveness of RIRD; however, this effect was not apparent with NCR. These findings suggest that different types of data analysis can influence the perceived success of a treatment.

The prevalence of hoarding (collection of and refusal to discard unneeded items) is higher in older adults than the general population and has been correlated with dementia. Treatments to increase cooperation with discarding hoarded items have not been systematically evaluated. This study evaluated two procedures for increasing cooperation with handing over hoarded items in an older adult with dementia. The antecedent‐based intervention effectively increased cooperation.