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O objetivo do estudo foi verificar se cinco usuários de implante coclear aprenderiam discriminações condicionais auditivo-visuais com e sem o auxílio de pistas orofaciais e se formariam classes de estímulos equivalentes, em dois problemas de aprendizagem. Em cada problema foram ensinadas relações condicionais entre palavras faladas e figuras e entre palavras faladas e estímulos textuais, a partir do emparelhamento com o modelo. Para alguns participantes, se erros fossem cometidos em tentativas auditivo-visuais, as mesmas eram repetidas com pistas orofaciais. Testes de formação de classes de equivalência avaliaram se os participantes estabeleceriam relações condicionais não ensinadas diretamente. Testes adicionais avaliaram os repertórios expressivos e receptivos antes e depois das tarefas de ensino. Os participantes aprenderam as relações condicionais com e sem o uso de pistas orofaciais progredindo da aprendizagem de palavras convencionais até pseudopalavras. Quatro participantes formaram classes de estímulos equivalentes no Problema 1 e dois participantes formaram classes de estímulos equivalentes no Problema 2. Melhores desempenhos foram observados nos testes finais dos repertórios expressivos e receptivos em relação aos desempenhos iniciais. O uso de pistas orofaciais combinado com procedimentos de ensino de discriminações condicionais parece favorecer o desempenho de usuários de implante coclear nas tarefas receptivas e expressivas.

Abstract When reinforcers of different magnitudes are concurrently available, choice is greater for a large reinforcer; that choice can be reduced by delaying its delivery, a phenomenon called delay discounting and represented graphically by a delay curve in which choice is plotted as a function of delay to the large reinforcer. Morphine, administered acutely, can alter responding for large, delayed reinforcers. In this study, the impact of morphine tolerance, dependence and withdrawal on choice of delayed reinforcers was examined in six pigeons responding to receive a small amount of food delivered immediately or a larger amount delivered immediately or after delays that increased within sessions. Acutely, morphine decreased responding for the large reinforcer, and the effect was greater when morphine was administered immediately, rather than 6 hr, before sessions. During 8 weeks of daily administration, morphine produced differential effects across pigeons, shifting the delay curve downward in some and upward in others. In all pigeons, tolerance developed to the response‐rate‐decreasing effects of morphine but not to its effects on delay discounting. When chronic morphine treatment was discontinued, rate of responding decreased in four pigeons, indicating the emergence of withdrawal; choice of the large reinforcer increased, regardless of delay, in all pigeons, an effect that persisted for weeks. These data suggest that chronic morphine administration has long‐lasting effects on choice behavior, which might impact vulnerability to relapse in opioid abusers.

Abstract It has been suggested that a fixed condition sequence might facilitate differential responding during multielement functional analyses (FAs) by capitalizing on or limiting sequence effects (Iwata, Pace, et al., 1994); however, the effects of condition sequence have not been examined empirically. We conducted fixed‐ and random‐sequence FAs for 7 individuals with developmental disabilities to determine the relative effects that sequence may have on assessment outcomes. Experimental conditions during the fixed sequence were conducted in the following order: ignore, attention, play, and demand; condition order during the random sequence was determined randomly. Results showed that sequence had no influence on the FA outcomes for 3 subjects, whereas differential responding emerged either faster (1 subject) or only (3 subjects) under the fixed sequence for the remaining subjects. These results suggest that the fixed sequence, a simple modification, should be used when conducting multielement FAs to accommodate the influence of establishing operations across assessment conditions.

Abstract In both humans and nonhumans, prior research demonstrates increased preference for larger‐later over smaller‐sooner rewards when rewards are bundled together in a series (i.e., when an operant choice produces multiple discrete reward deliveries, as opposed to only a single delivery). These findings can be predicted using a traditional hyperbolic delay‐discounting model. The present study was designed to examine the parametric effects of the size of the reward bundle on larger‐later reward preference in male rats. During a reward‐bundling phase, rats were exposed to bundle‐sizes of either 1 (i.e., no bundling), 3, or 9 rewards. Rats in the Bundle‐size 9 group showed significantly greater larger‐later reward preference across a range of delays (0‐17.5 s) than rats in any other group, but no other significant differences in choice were observed between groups. In addition, when choice for unbundled rewards was assessed following the reward‐bundling phase, rats in the Bundle‐size 9 group showed a significant increase in larger‐later reward preference (compared to a pre‐test). Obtained data from the reward‐bundling phase are compared to model‐predicted data, and potential mechanisms of the observed increase in self‐control for unbundled rewards are discussed.

Abstract A common condition included in most functional analyses (FAs) is the attention condition, in which the therapist ignores the client by engaging in a solitary activity (antecedent event) but delivers attention to the client contingent on problem behavior (consequent event). The divided attention condition is similar, except that the antecedent event consists of the therapist conversing with an adult confederate. We compared the typical and divided attention conditions to determine whether behavior in general (Study 1) and problem behavior in particular (Study 2) were more sensitive to one of the test conditions. Results showed that the divided attention condition resulted in faster acquisition or more efficient FA results for 2 of 9 subjects, suggesting that the divided attention condition could be considered a preferred condition when resources are available.

Abstract We evaluated a discrete‐trial functional analysis implemented by regular classroom staff in a classroom setting. The results suggest that the discrete‐trial functional analysis identified a social function for each participant and may require fewer staff than standard functional analysis procedures.

Abstract Response membership in pigeons' stimulus‐class formation was evaluated using associative symmetry and class expansion tests. In Experiment 1, pigeons learned hue–hue (AA) and form–form (BB) successive matching plus a modified hue–form (AB) task in which reinforcement was contingent upon a left versus right side‐key response after the positive AB sequences. On subsequent BA (symmetry) probe trials, pigeons responded more often to the comparisons on the reverse of the positive than negative AB sequences and, more importantly, preferentially pecked the side key consistent with symmetry after the reversed positive sequences. In Experiment 2, the original three baseline tasks were supplemented by dot–white (CC) successive matching in which reinforcement was contingent upon a left versus right side‐key response after the positive CC sequences. Class expansion was then tested by presenting nonreinforced CA and CB successive matching probes. Comparison response rates were mostly nondifferential on CA probes but were uniformly higher on CB probes that consisted of the C samples and B comparisons from the same, hypothesized class. Together, these results provide evidence that responses can become members of stimulus classes, as predicted by Urcuioli's (2008) theory of pigeons' stimulus‐class formation and Sidman's (2000) theory of equivalence.

Abstract Some individuals engage in both mild and severe forms of problem behavior. Research has shown that when mild behaviors precede severe behaviors (i.e., the mild behaviors serve as precursors), they can (a) be maintained by the same source of reinforcement as severe behavior and (b) reduce rates of severe behavior observed during assessment. In Study 1, we developed an objective checklist to identify precursors via videotaped trials for 16 subjects who engaged in problem behavior and identified at least 1 precursor for every subject. In Study 2, we conducted separate functional analyses of precursor and severe problem behaviors for 8 subjects, and obtained correspondence between outcomes in 7 cases. In Study 3, we evaluated noncontingent reinforcement schedule thinning plus differential reinforcement of alternative behavior to reduce precursors, increase appropriate behavior, and maintain low rates of severe behavior during 3 treatment analyses for 2 subjects. Results showed that this treatment strategy was effective for behaviors maintained by positive and negative reinforcement.