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Abstract Organisms often prefer conditions that allow selection among alternatives (free‐choice) to conditions that do not (forced‐choice), particularly when response alternatives in free‐choice produce equal or greater reinforcer magnitudes than those available under forced‐choice. We present data on free‐choice preference for human participants who gained or lost points by selecting images of cards on a computer screen under a concurrent‐chains schedule. Responding during the initial link gained access to a terminal link offering a single‐card set (forced‐choice) or a three‐card set (free‐choice). The alternatives in free‐choice produced reinforcer magnitudes (points) that were: (a) equal to forced‐choice; (b) equal to and greater than forced‐choice; and (c) equal to and less than forced‐choice. Participants showed reliable preference for free‐choice under some conditions; however, preference decreased as reinforcer magnitude for some alternatives in free‐choice was reduced. This occurred even though it was possible to obtain the same number of points across free‐ and forced‐choice. Although preference for free‐choice was clearly demonstrated, the effect of points available in the terminal link suggests that this phenomenon is subject to modulation by other processes, such as reinforcement or punishment by obtained outcomes in the terminal link. Context (reinforcer‐gain or ‐loss) was not a reliable predictor of preference.

We evaluated the effects of white noise played through headphones on off‐task behavior, percentage of items completed, and percentage of items completed correctly for 3 students with attention deficit hyperactivity disorder (ADHD). Headphones plus white noise were associated with decreases in off‐task behavior relative to baseline and headphones‐only (no white noise) control conditions. Little change in academic responding occurred across conditions for all participants.

Para analizar el efecto de diferentes estrategias, simuladas por una computadora, en la adquisición de respuestas cooperativas; se entrenó a siete palomas a jugar el dilema del prisionero reiterado en contra de un oponente, simulado por una computadora, que empleaba una de tres posibles estrategias: (1) seleccionar la misma estrategia que eligió la paloma en el ensayo previo (Tic-for-Tat, TFT), (2) cooperar o traicionar aleatoriamente en cada ensayo (Random, RND) y (3) cooperar cuando la paloma traicionaba o traicionar cuando la paloma cooperaba (estrategia individualizada, I). En cada ensayo las palomas recibieron acceso diferencial al alimento después de picar la tecla asociada a la estrategia de cooperar o traicionar, por tanto, el tiempo de acceso al alimento dependía de la estrategia asignada a la computadora. Durante el experimento se entrenó a los sujetos en las tres posibles condiciones (TFT, RND o I) durante 30 sesiones de manera contrabalanceada. Los resultados muestran un mayor porcentaje de respuestas cooperativas en los sujetos que enfrentaron a un oponente que empleaba la estrategia TFT. Adicionalmente, se observó que el porcentaje de respuestas cooperativas en la condición TFT disminuyó cuando esta condición era antecedida por las condiciones RND e I. Los resultados se discuten en términos de otros estudios sobre cooperación.

O uso do adjetivo radical para identificar a variedade de behaviorismo proposta por Skinner é corrente nos dias atuais. Entretanto, historicamente, esse qualificador não foi exclusivamente aplicado à proposta skinneriana e seu caráter polissêmico tende a gerar incorreções na interpretação do que caracteriza o Behaviorismo Radical de Skinner. Este artigo pretende esclarecer o sentido mais apropriado de radical quando aplicado ao behaviorismo de Skinner por meio de quatro atividades articuladas: (1) a recuperação das origens etimológicas da palavra radical e seus diferentes significados em Língua Portuguesa, Língua Espanhola e Língua Inglesa; (2) uma reconstrução e análise evolutiva de um cenário histórico que culminou no uso do termo no contexto behaviorista; (3) uma análise das principais acepções de radical quando associadas ao behaviorismo; (4) um exame dos sentidos em que é coerente a adoção do termo radical associado ao behaviorismo e das implicações correntes e futuras para o Behaviorismo Radical e a Análise do Comportamento no contexto científico.

Empirical studies have demonstrated that class‐specific contingencies may engender stimulus–reinforcer relations. In these studies, crossmodal relations emerged when crossmodal relations comprised the baseline, and intramodal relations emerged when intramodal relations were taught during baseline. This study investigated whether auditory–visual relations (crossmodal) would emerge after participants learned a visual–visual baseline (intramodal) with auditory stimuli presented as specific consequences. Four individuals with autism learned AB and CD relations with class‐specific reinforcers. When A1 and C1 were presented as samples, the selections of B1 and D1, respectively, were followed by an edible (R1) and a sound (S1). Selections of B2 and D2 under the control of A2 and C2, respectively, were followed by R2 and S2. Probe trials tested for visual–visual AC, CA, AD, DA, BC, CB, BD, and DB emergent relations and auditory–visual SA, SB, SC, and SD emergent relations. All of the participants demonstrated the emergence of all auditory–visual relations, and three of four participants showed emergence of all visual–visual relations. Thus, the emergence of auditory–visual relations from specific auditory consequences suggests that these relations do not depend on crossmodal baseline training. The procedure has great potential for applied technology to generate auditory–visual discriminations and stimulus classes in the context of behavior‐analytic interventions for autism.

Abstract We examined the use of employment‐based abstinence reinforcement in out‐of‐treatment injection drug users, in this secondary analysis of a previously reported trial. Participants ( N = 33) could work in the therapeutic workplace, a model employment‐based program for drug addiction, for 30 weeks and could earn approximately $10 per hr. During a 4‐week induction, participants only had to work to earn pay. After induction, access to the workplace was contingent on enrollment in methadone treatment. After participants met the methadone contingency for 3 weeks, they had to provide opiate‐negative urine samples to maintain maximum pay. After participants met those contingencies for 3 weeks, they had to provide opiate‐ and cocaine‐negative urine samples to maintain maximum pay. The percentage of drug‐negative urine samples remained stable until the abstinence reinforcement contingency for each drug was applied. The percentage of opiate‐ and cocaine‐negative urine samples increased abruptly and significantly after the opiate‐ and cocaine‐abstinence contingencies, respectively, were applied. These results demonstrate that the sequential administration of employment‐based abstinence reinforcement can increase opiate and cocaine abstinence among out‐of‐treatment injection drug users.

We assessed the immediate and subsequent effects of environmental enrichment (EE) as a stand‐alone intervention and when EE was combined with response cost (RC) for 5 participants using a 2‐component multiple‐schedule design. Environmental enrichment failed to decrease any participant's immediate engagement in stereotypy; however, the addition of RC decreased the immediate engagement in stereotypy for all participants. After the withdrawal of EE plus RC, stereotypy did not immediately increase for 3 of 5 participants.

Esta pesquisa investigou o efeito do uso de um jogo de tabuleiro na formação de classe de equivalência de estímulos e na avaliação e escolhas alimentares, realizadas por meio de figuras por crianças que fazem seleção restritiva alimentar. Participaram da pesquisa duas crianças com idades de sete e oito anos. A pesquisa teve seis etapas: investigação sobre os hábitos alimentares, pré-teste de avaliação e pré-teste das escolhas alimentares, intervenção/jogo, ensino do procedimento MTS, teste das propriedades emergentes e verificação/pós-teste. Inicialmente os participantes assinalaram em uma folha suas escolhas e preferências por alimentos (pré-teste). Na etapa de intervenção, foram conduzidas oito sessões com o jogo, o qual visou ensinar as relações AB e AC. Cada classe de estímulos era composta por três figuras: classe A - cestas de supermercado; B - grupos alimentares e a C - mãos indicando positivo. Posteriormente, testaram-se as relações AA, BB, CC, BA, CA, CB e BC, seguido pelo pós-teste. Houve formação de classes equivalentes. Para um dos participantes houve mudanças na avaliação e escolhas alimentares e, segundo os responsáveis, ambos os participantes consumiram alimentos que não consumiam antes da intervenção. Discutem-se as variáveis presentes no jogo que podem ter contribuído para que os participantes consumissem novos alimentos.

The use of behavioral skills training (BST) to educate 3 adolescent boys on the risks of lighters and fire setting was evaluated using in situ assessment in a school setting. Two participants had a history of fire setting. After training, all participants adhered to established rules: (a) avoid a deactivated lighter, (b) leave the training area, and (c) report the lighter to an adult. The response sequence was maintained for both participants after training. The use of in situ assessment to evoke and observe infrequent behavior is discussed.

Mephedrone (4‐methylmethcathinone) has been found in several over‐the‐counter products that are abused by humans, but very little is known about its behavioral effects and abuse liability. The present study examined the effects of mephedrone (1–10 mg/kg) on learning in female rats, as well as its interaction with the ovarian hormone estradiol. More specifically, female rats were trained to respond under a multiple schedule of repeated acquisition and performance of response sequences and then ovariectomized. Following ovariectomy, mephedrone dose‐effect curves were obtained during periods of 17β‐estradiol administration and periods without estradiol administration. Unlike mephedrone, which was administered acutely (i.p.) before the experimental sessions, 17β‐estradiol was administered via subcutaneous Silastic capsules containing 25% 17β‐estradiol and 75% cholesterol. In general, mephedrone produced dose‐dependent rate‐decreasing and error‐increasing effects in the acquisition and performance components of the schedule in all subjects. However, when estradiol was present, three of the four rats were more sensitive to the rate‐decreasing effects of mephedrone, and all of the subjects were more sensitive to its error‐increasing effects. These data indicate that estradiol can potentiate the disruptive effects of mephedrone on both the acquisition and performance of complex behavior in female rats.