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Primates take longer to choose between alternatives with smaller differences in value. This effect—a particular instance of the distance effect in symbolic comparisons—has not been replicated in birds. Instead, birds appear to respond independently to each alternative, such that the latency to choose depends primarily on the alternative of highest value. Three experiments tested for the distance effect in pigeons under conditions not previously considered. Experiment 1 presented pigeons with forced‐ and binary free‐choice trials, where each alternative was one of three possible delays to reinforcement (4, 8, and 16 s). Pigeons were exposed to the choice stimuli for different amounts of time and with different sample response requirements prior to the choice response. Experiment 2 added a fourth (0‐s delay) alternative. Experiment 3 substituted the 16‐s delay with a second 4‐s delay. In all experiments, pigeons systematically chose the shortest delay to reinforcement. Latency to choose the 4‐s delay did not vary when choosing against the 8‐s or 16‐s delay, regardless of whether choice stimuli were exposed for the duration of nine pecks (Experiment 1), or whether a 0‐s delay alternative was sometimes present (Experiment 2). Latency to choose the preferred of two identical alternatives (4‐s vs. 4‐s) was shorter than the latency to choose between different alternatives (4‐s vs. 8‐s; Experiment 3); this is the opposite of a distance effect. These results show no evidence of a distance effect in pigeon choice, consistent with the hypothesis that pigeons respond independently to each choice alternative.

Hagopian, Rooker, and Zarcone (2015) evaluated a model for subtyping automatically reinforced self‐injurious behavior ( SIB ) based on its sensitivity to changes in functional analysis conditions and the presence of self‐restraint. The current study tested the generality of the model by applying it to all datasets of automatically reinforced SIB published from 1982 to 2015. We identified 49 datasets that included sufficient data to permit subtyping. Similar to the original study, Subtype‐1 SIB was generally amenable to treatment using reinforcement alone, whereas Subtype‐2 SIB was not. Conclusions could not be drawn about Subtype‐3 SIB due to the small number of datasets. Nevertheless, the findings support the generality of the model and suggest that sensitivity of SIB to disruption by alternative reinforcement is an important dimension of automatically reinforced SIB . Findings also suggest that automatically reinforced SIB should no longer be considered a single category and that additional research is needed to better understand and treat Subtype‐2 SIB .

We compared the results of a brief video‐based multiple‐stimulus without replacement preference assessment with no access to chosen activities ( MSWO‐NO ) to the results of the same assessment with access ( MSWO‐WA ) with four children with autism. We also compared instructor rankings of activities to MSWO‐WA results. Strong to moderate correlations between MSWO‐NO and MSWO‐WA assessment results were found across all participants. The correlation between MSWO‐WA and instructor rankings ranged from strong to low across all participants. Implications and directions for future research are discussed.

Differential‐reinforcement treatments reduce target problem behavior in the short term but at the expense of making it more persistent long term. Basic and translational research based on behavioral momentum theory suggests that combining features of stimuli governing an alternative response with the stimuli governing target responding could make target responding less persistent. However, changes to the alternative stimulus context when combining alternative and target stimuli could diminish the effectiveness of the alternative stimulus in reducing target responding. In an animal model with pigeons, the present study reinforced responding in the presence of target and alternative stimuli. When combining the alternative and target stimuli during extinction, we altered the alternative stimulus through changes in line orientation. We found that (1) combining alternative and target stimuli in extinction more effectively decreased target responding than presenting the target stimulus on its own; (2) combining these stimuli was more effective in decreasing target responding trained with lower reinforcement rates; and (3) changing the alternative stimulus reduced its effectiveness when it was combined with the target stimulus. Therefore, changing alternative stimuli (e.g., therapist, clinical setting) during behavioral treatments that combine alternative and target stimuli could reduce the effectiveness of those treatments in disrupting problem behavior.

The go/no‐go with compound stimuli is an alternative to matching‐to‐sample to produce conditional and emergent relations in adults. The aim of this study was to evaluate the effectiveness of this procedure with two children diagnosed with autism. We trained and tested participants to respond to conditional relations among arbitrary stimuli using the go/no‐go procedure. Both learned all the trained conditional relations without developing response bias or responding to no‐go trials. Participants demonstrated performance consistent with symmetry, but not equivalence.

Robotics is emerging as a promising tool for aiding research on animal behavior. The possibility of generating customizable, controllable, and standardized robotic stimuli has been demonstrated through a number of behavioral assays, involving vertebrates and invertebrates. However, the specific appraisal of the nature of robotic stimuli is currently lacking. Here, we attempt to evaluate this aspect in zebrafish, through a within‐subject design in which experimental subjects are faced with three experimental conditions. In the first test, we investigated sociability by measuring zebrafish response to a conspecific separated by a one‐way glass. In the second test, we studied zebrafish behavior in response to a 3D ‐printed zebrafish replica actuated along realistic trajectories through a novel four‐degree‐of‐freedom robotic platform. Last, we investigated fear responses in a shelter‐seeking test. In agreement with our expectations, zebrafish exhibited an equivalent preference for live and robotic stimuli, and the degree of preference for the robotic replica correlated negatively with the individual propensity to seek shelter. The equivalent preference for the replica and conspecific suggests that the appraisal of the target stimuli is analogous. The preliminary evidence of a correlation between behavioral responses across tests points to the readability of robotics‐based approaches to investigate interindividual differences.