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Impulsive choice behavior incorporates the psychological mechanisms involved in the processing of the anticipated magnitude and delay until reward. The goal of the present experiment was to determine whether individual differences in such processes related to individual differences in impulsive choice behavior. Two groups of rats (Delay Group and Magnitude Group) were initially exposed to an impulsive choice task with choices between smaller–sooner (SS) and larger–later (LL) rewards. The Delay Group was subsequently exposed to a temporal discrimination task followed by a progressive interval task, whereas the Magnitude Group was exposed to a reward magnitude sensitivity task followed by a progressive ratio task. Intertask correlations revealed that the rats in the Delay Group that made more self‐controlled (LL) choices also displayed lower standard deviations in the temporal bisection task and greater delay tolerance in the progressive interval task. Impulsive choice behavior in the Magnitude Group did not display any substantial correlations with the reward magnitude sensitivity and progressive ratio tasks. The results indicate the importance of core timing processes in impulsive choice behavior, and encourage further research examining the effects of changes in core timing processes on impulsive choice.

This study extended previous research on equivalence relations established with outcome‐specific reinforcers to include the merger of separately established stimulus classes. Participants were four adults. Conditional discriminations AC and BC were trained first. Correct selections of C1 (C2, or C3) in the presence of A1 or B1 (A2 or B2, or A3 or B3) were followed by red (blue, or white) tokens; tokens were exchanged for value added to three participant‐selected gift cards. Outcomes on equivalence tests for three‐member classes ABC were positive. DF and EF were trained with the same reinforcing consequences, and tests were positive for three‐member classes DEF. Results of class merger tests with combinations of stimuli from the ABC and DEF classes (AD, FB, etc.) were immediately positive for two participants, demonstrating six‐member classes ABCDEF with reinforcers as nodes. Merger tests for a third participant were initially negative but became positive after brief exposure to unreinforced probe trials with reinforcers as comparison stimuli. Following class merger, tests for matching the reinforcers to samples and comparisons were also positive. Class‐merger test results were negative for a fourth participant. The results provide the first demonstration of eight‐member equivalence classes including two outcome‐specific conditioned reinforcing stimuli.

Problem behavior often has sensory consequences that cannot be separated from the target response, even if external, social reinforcers are removed during treatment. Because sensory reinforcers that accompany socially mediated problem behavior may contribute to persistence and relapse, research must develop analog sensory reinforcers that can be experimentally manipulated. In this research, we devised analogs to sensory reinforcers in order to control for their presence and determine how sensory reinforcers may impact treatment efficacy. Experiments 1 and 2 compared the efficacy of differential reinforcement of alternative behavior (DRA) versus noncontingent reinforcement (NCR) with and without analog sensory reinforcers in a multiple schedule. Experiment 1 measured the persistence of key pecking in pigeons, whereas Experiment 2 measured the persistence of touchscreen responses in children with intellectual and developmental disabilities. Across both experiments, the presence of analog sensory reinforcers increased the levels, persistence, and variability of responding relative to when analog sensory reinforcers were absent. Also in both experiments, target responding was less persistent under conditions of DRA compared to NCR regardless of the presence or absence of analog sensory reinforcers.

Previous research has indicated both petting (McIntire & Colley, 1967) and food (Feuerbacher & Wynne, 2012) have reinforcing effects on dog behavior and support social behavior towards humans (food: Elliot & King, 1960; social interaction: Brodbeck, 1954). Which type of interaction dogs prefer and which might produce the most social behavior from a dog has not been investigated. In the current study, we assessed how dogs allocated their responding in a concurrent choice between food and petting. Dogs received five 5‐min sessions each. In Session 1, both food and petting were continuously delivered contingent on the dog being near the person providing the respective consequence. Across the next three sessions, we thinned the food schedule to a Fixed Interval (FI) 15‐s, FI 1‐min, and finally extinction. The fifth session reversed back to the original food contingency. We tested owned dogs in familiar (daycare) and unfamiliar (laboratory room) environments, and with their owner or a stranger as the person providing petting. In general, dogs preferred food to petting when food was readily available and all groups showed sensitivity to the thinning food schedule by decreasing their time allocation to food, although there were group and individual differences in the level of sensitivity. How dogs allocated their time with the petting alternative also varied. We found effects of context, familiarity of the person providing petting, and relative deprivation from social interaction on the amount of time dogs allocated to the petting alternative.

O objetivo do presente trabalho foi investigar o efeito da exposição à contingência e a diferentes regras sobre o desempenho em DRL e sobre a sensibilidade comportamental. Foram realizados dois experimentos que se diferenciavam quanto à necessidade da resposta de consumação para a obtenção do reforço. Na Fase 1, os grupos foram caracterizados de acordo com a instrução fornecida: Grupo IM (Instrução Mínima), Grupo IC (Instrução Correspondente) e Grupo ID (Instrução Discrepante). O programa de reforço DRL 5 s estava em vigor. Na Fase 2, estava em vigor a Extinção. No Experimento 1 houve a necessidade da resposta de consumação para a obtenção do reforço. Os resultados dos participantes do Experimento 1 durante a Fase 1 demonstraram que, de 15 participantes, 13 emitiram baixas taxas de resposta; os participantes do Grupo IC e do Grupo ID emitiram taxas de repostas inicialmente altas. Os dados da Fase 2 apontam que, o comportamento dos participantes do Grupo IC apresentou menor proporção de mudança em comparação aos participantes dos demais grupos. No Experimento 2, não houve a necessidade da resposta de consumação para a obtenção do reforço. Os resultados do Experimento 2 replicam os do Experimento 1, contudo os participantes do Grupo IC, do Experimento 2, não emitiram taxas inicias altas.

O Jato de Ar Quente (JAQ) é um estímulo aversivo alternativo ao choque elétrico. Entretanto, pouco ainda se sabe sobre quais respostas são produzidas pelo seu contato com o organismo. O objetivo do presente estudo foi realizar o mapeamento de tais respostas e como elas estariam relacionadas com a supressão do responder em contextos de punição. No Experimento 1, o JAQ foi apresentado em um esquema não-contingente (VT- 3min). No Experimento 2, o JAQ foi apresentado em um esquema contingente como punição da resposta de pressionar a barra (FR-1 de punição + VI-60s de reforçamento). As sessões foram todas filmadas. Foram categorizadas as respostas observadas durante o acionamento de cada JAQ, bem como os trinta segundos antes e os trinta segundos depois da apresentação desse estímulo. As principais respostas registradas no Experimento 1 foram: abaixar, esticar, andar, farejar e varredura. No Experimento 2, por sua vez, foram: posicionar-se sobre a barra, farejar o teto, contato com o corpo, levantar e varredura. As respostas registradas, em sua maioria, principalmente no Experimento 2, eram relacionadas ao afastamento da região da barra e do comedouro, podendo ser interpretadas como concorrentes à resposta de pressionar a barra. Uma discussão da compatibilidade destes dados com a perspectiva assimétrica de explicação da punição, como a oferecida por Skinner, é apresentada. Palabras-clave: Jato de Ar Quente, Punição, Estímulo Aversivo, Simetria e Assimetria.

Este artigo descreve o comportamento de gaguejar de um adulto de 25 anos no contexto de alguns aspectos de sua história de aprendizagem e de situações interpessoais que enfrentava em seu cotidiano. Tanto as dificuldades de fala no cotidiano, quanto o próprio processo do tratamento foram analisados em relação às maneiras como o cliente lidava com os aspectos aversivos inseridos nessas situações. Durante o tratamento, foram estabelecidos alguns comportamentos que permitiam ao cliente responder melhor aos desafios do contato interpessoal. A terapia trabalhou a dificuldade do cliente de se posicionar frente aos problemas inerentes nas situações de fala. Essas intervenções visaram, não somente os problemas do cliente no seu dia-a-dia a partir de seu relato, mas também, o comportamento espontâneo do cliente no relacionamento pessoal com o terapeuta a partir de aspectos observados diretamente em sessão. O artigo discute que o entrelaçamento do foco sobre comportamentos relatados pelo cliente com o foco sobre o relacionamento terapêutico levou à diminuição da frequência da resposta de gaguejar, à generalização para as situações de falar e de condições interpessoais que ele relatava como difíceis, enquanto que, a possibilidade de gaguejar perdeu o seu efeito aversivo e ameaçador para ele.

Equivalence‐based instruction of college students was adapted for use in a commercial online course‐delivery system, with written explanation replacing match‐to‐sample training. Outcomes rivaled those of previous studies in which students were taught in low‐distraction settings through match‐to‐sample procedures that were controlled by custom computer programs, demonstrating that such supports are not essential to the effectiveness of equivalence‐based instruction.

Shabani, Carr, and Petursdottir (2009) examined the effects of a response–response relation (effort) on the development of a response‐class hierarchy using a laboratory model. Response–reinforcer relations may have similar influences. Using a similar translational approach, we examined the effects of reinforcer rate, quality, delay, and magnitude in a series of separate experiments conducted with 8 individuals with intellectual disabilities. Response‐class hierarchies emerged along the dimension of rate for 3 of 6 subjects, quality for 5 of 5 subjects, delay for 2 of 8 subjects, and magnitude for 5 of 6 subjects.

The effects of intermittent schedules of reinforcement for pausing were evaluated in two experiments. In Experiment 1, across a series of conditions, a variable‐interval (VI) baseline schedule, in which pigeons' key pecks produced food, alternated with conditions in which food was delivered according to a concurrent VI (for key pecking) tandem variable‐time differential‐reinforcement‐of‐other‐behavior (DRO) 5‐s schedule. Time spent pausing within a session was proportional to the reinforcement rates associated with the tandem schedule. To examine the control of pausing by antecedent events, Experiment 2 arranged a multiple schedule in which pecking and pausing in either component were maintained according to concurrent schedules like those used in the first experiment. The availability of reinforcement for pausing was signaled in one component while signals uncorrelated with reinforcement were presented in the other. Signaled reinforcement for pausing, relative to the presentation of uncorrelated signals, decreased time spent pausing, a finding consistent with existing research on the effects of signaled VI reinforcement for key pecking in pigeons. The results of the two experiments show that pausing functions as an operant in much the same way that discrete responses, like key pecks, do, and that pausing and other operants are similarly affected by both antecedent and consequent events.