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In this study, 2-minute and 5-minute free operant preference assessments were conducted. Preference hierarchies and the order of item selection were both identified and compared. The preference assessments were administered in alternating order and the resulting differentially preferred items were utilized in subsequent reinforcer assessments to determine if the items selected were reinforcing. The reinforcer assessments were conducted using an initial baseline and an alternating treatment design. Social validity was assessed with both the families and the participants. Treatment fidelity and inter-observer agreement data were also collected. The 2-minute free operant preference assessment was shown to be effective at identifying effective reinforcers for two out of the three participants. The third participant did not respond consistently to the free operant preference assessment at any length and responded aversively to the presentation of the free operant preference assessment, one which is known for yielding few problem behaviors. For the two participants that responded to the preference assessment, items that were identified functioned effectively as reinforcers. There was also a strong correlation using the Spearman’s Rank-Order Correlation Coefficient between the preference hierarchies and the order of selection list. This study supports the usage of the shortened free operant preference assessment but requires expansion and repetition. The author discussed the limitations of the current study and directions for future research. / Applied Behavioral Analysis

Motivating individuals with autism can be challenging for clinicians and educators seeking to increase skills or decrease problem behaviors. Even when highly preferred reinforcers have been identified, they tend to lose their effectiveness over time. Over the years, several strategies have been developed to maintain the effectiveness of reinforcers. Reinforcer variation has been demonstrated to attenuate decreases in responding associated with repeated exposure to a single reinforcer. Another strategy that has been used to help maintain responding is allowing an individual a choice among reinforcers. Several researchers have suggested that providing choice among several reinforcers may produce the same effects on responding as reinforcer variation. Although these two procedures have been shown to maintain motivation in individuals with autism, they have not been systematically compared and evaluated against each other. In this study, we evaluated the effects of reinforcer variation as compared to reinforcer choice.

Deficits in conversation skills can be one barrier to developing and maintaining relationships for individuals with autism spectrum disorder (ASD). Individuals with ASD may deter conversation partners if they do not stay on topic or if they dwell on topics. Several interventions have been identified in targeting the reduction of problematic (off-topic or perseverative) speech, and withheld attention for its occurrence. In addition to leveraging attention as a reinforcer, one study provided signaled access to preferred topics contingent on talking about non-perseverative or therapist-selected topics. Despite showing clear improvements in on-topic speech and stimulus control of preferred topics, little is known about the additive effects of including contingent access to preferred topics. A free operant assessment was used to evaluate participant preference for including access to preferred topics. The results indicated that participants preferred the proposed intervention with access to a leisure item.

The present study investigated how heightened P3a effects may be induced using a free-operant paradigm rather than traditional two and three stimulus oddballs. This was accomplished by using a fixed set of stimuli and mixed FR5 and VR5 reinforcement schedules. Most participants showed heightened P3a effects in the VR5 conditions, but a few participants did not. The data for the group that did not show the P3a effect in their data were variable, and definite conclusions about the factors related to the non-occurrence of the P3a were not researched. Despite this, there appears to be a relation between operant behavior dimensions (i.e., reaction time and response rate) and the P3a effect, with higher reaction times and lower response rates correlated to more significant P3a effects. Limitations discussed include the use of too simple of a behavioral topography and the lack of anecdotal participant interviews that could shed light on deviant performances.

Research on aversive control of behaviour has dramatically declined over the past decades. This trend is primarily a consequence of an over-reliance on shock-based procedures, which have been increasingly criticized on ethical, practical, and ecological validity grounds. The continued study of aversive regulation thus requires the development of viable alternatives. Six preliminary experiments, triggered by serendipitous observations of Betta splendens’ reactions to unintended water disturbances, allowed for (a) developing a water flows (WFs) experimental paradigm; (b) confirming the aversive function of WFs; and (c) demonstrating the feasibility of the WFs paradigm as an alternative to the use of electric shock, as it does not involve painful stimulation and carries a higher level of inherent ecological validity. Based on the relevance of free-operant avoidance phenomena (Sidman, 1953a) for the study of aversive control, the fact that these have only been demonstrated in one fish species (goldfish) using shocks, and that the only attempt to show another form of avoidance in Betta splendens produced inconclusive results (Otis & Cerf, 1963), the WFs paradigm was implemented in two experiments aimed at addressing these issues. These studies were aligned with a research program on spatiotemporal analysis of behaviour that has demonstrated, over the course of several decades, that a comprehensive understanding of behavioural processes requires an approach that includes, but is not limited to, the study of rates of discrete responses (e.g., key pecks of a pigeon). Accordingly, a more holistic interpretation of experimental data than is typical for behavioural studies was attained through a combined analysis of the frequency and temporal distribution of a target response (crossings in a shuttle-tank), patterns of swimming trajectories, instances and durations of the aversive stimulus, and the occurrence of behaviour related to different features of the experimental tank. In Experiment 1, Betta splendens exposed to a free-operant avoidance procedure reliably escaped WFs but did not develop avoidance behaviour even though escape improved with practice. Moreover, adding a warning stimulus (curtains of air bubbles - CABs) to the free-operant procedure did not produce increments in avoidance behaviour, as has been demonstrated in other species. Considering these findings, Experiment 2 maintained the same free-operant avoidance contingencies, but escape responses were now scheduled to produce the WFs (punishment and extinction of escape). The result of this manipulation was not a substantial decrease of escape, but an initial large increase of this response, followed by a progressive decrease to approximately pre-punishment levels. In addition, punishment did not result in increased avoidance responding as an alternative response. The explanations for these unexpected findings relate to the duration of the CABs; sign- and goal-tracking effects; uncontrolled stimulation produced by water pump activation/operation; unintended reinforcement (mirror reflections and delay between the pump activation and WFs reaching full strength); and the development of responses that allowed the fish to reduce their exposure to high-intensity WFs (i.e., alternative behaviour). The need for investigating the effects of adjusting the WF procedures to the ecology and biology of Betta splendens is also discussed, particularly in regard to their territoriality and predominant defensive response (immobility) in relation to the experimental apparatuses and the target response (changing compartments).