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Se expuso a seis palomas, privadas de comida a un ciclo de tiempo repetitivo (ciclo T) constante en 24 s que terminaba con la iluminación de una tecla de respuesta en blanco o rojo durante 4 s y la presentación posterior del dispensador de comida. Los sujetos podían comer del dispensador solo cuando su presentación era precedida por la tecla iluminada de blanco; cuando los sujetos se aproximaban al dispensador precedido por la tecla en rojo, el dispensador se retiraba y se presentaba un apagón de luces de una duración promedio de 5 s. En el Experimento 1 se alternó o se presentó al azar la tecla iluminada de blanco o de rojo, en condiciones sucesivas. En el Experimento 2 se varió en condiciones sucesivas la duración del dispensador de comida que seguía a la tecla iluminada de rojo. Las duraciones fueron 4 s, 1 s, 2 s, 1 s, 4 s. Globalmente, se encontró que la presentación al azar del color de la tecla facilitó la adquisición de la conducta autocontrolada de "abstenerse" de consumir la comida subsecuente. Variar la duración del reforzador precedido por la tecla en rojo facilitó el moldeamiento de la conducta de "abstenerse" de consumir la recompensa. Se concluyó que es viable someter a control discriminativo la conducta autocontrolada de "abstenerse" de consumir una recompensa.

Contextual behavioral perspectives on learning and behavior reside under the umbrella of evolution science. In this paper we briefly review current developments in evolution science that bear on learning and behavior, concluding that behavior is now moving to the center of evolution studies. Learning is one of the main ladders of evolution by establishing functional benchmarks within which genetic adaptations can be advantaged. We apply that approach to the beginning feature of human cognition according to Relational Frame Theory: derived symmetry in coordination framing. When combined with the idea that cooperation came before major advances in human cognition or culture, existing abilities in social referencing, joint attention, perspective‐taking skills, and relational learning ensure that the behavioral subcomponents of symmetrical equivalence relations would be reinforced. When coordination framing emerged and came under arbitrary contextual control as an operant class, a template was established for the development of multiple relational frames and the emergence and evolutionary impact of human cognition as we know it. Implications of these ideas for translational research are briefly discussed.

Previous research that has evaluated the ability of sex offenders with intellectual disabilities (ID) to suppress sexual arousal has produced mixed results. The current study had 2 purposes: (a) to replicate prior research on arousal suppression by sex offenders with ID and (b) to evaluate whether it is possible for offenders with ID to maintain arousal to nondeviant stimuli while suppressing arousal to deviant stimuli. Both participants were successful in suppressing arousal to deviant stimuli, and 1 participant was successful in maintaining arousal to nondeviant stimuli while suppressing arousal to deviant stimuli.

Abstract The present study examined delay and probability discounting of hypothetical monetary losses over a wide range of amounts (from $20 to $500,000) in order to determine how amount affects the parameters of the hyperboloid discounting function. In separate conditions, college students chose between immediate payments and larger, delayed payments and between certain payments and larger, probabilistic payments. The hyperboloid function accurately described both types of discounting, and amount of loss had little or no systematic effect on the degree of discounting. Importantly, the amount of loss also had little systematic effect on either the rate parameter or the exponent of the delay and probability discounting functions. The finding that the parameters of the hyperboloid function remain relatively constant across a wide range of amounts of delayed and probabilistic loss stands in contrast to the robust amount effects observed with delayed and probabilistic rewards. At the individual level, the degree to which delayed losses were discounted was uncorrelated with the degree to which probabilistic losses were discounted, and delay and probability loaded on two separate factors, similar to what is observed with delayed and probabilistic rewards. Taken together, these findings argue that although delay and probability discounting involve fundamentally different decision‐making mechanisms, nevertheless the discounting of delayed and probabilistic losses share an insensitivity to amount that distinguishes it from the discounting of delayed and probabilistic gains.

Likelihood of equivalence class formation (yield) was influenced by pre‐class formation of simultaneous and successive discriminations, their mastery criteria, and overtraining of the successive discriminations. Each undergraduate in seven groups attempted to form two 3‐node, 5‐member equivalence classes (ABCDE). In the pictorial (PIC) group, meaningless nonsense syllables were used as the A, B, D, and E stimuli and meaningful pictures as the C stimuli. Nonsense syllables only were used in the other groups. The abstract (ABS) or 0‐0‐0 group involved no pre‐class training. In the 84‐0‐0, 84‐5‐0 and 84‐20‐0 groups, simultaneous discriminations were trained among C stimuli to a mastery criterion of 84 trials, followed by successive discriminations trained to mastery criteria of 0, 5, and 20 trials, respectively. In the 84‐20‐0, 84‐20‐100, and 84‐20‐500 groups, simultaneous and successive discriminations were trained as noted, followed by overtraining with 0, 100, 500 successive‐discrimination trials, respectively. The ABS group produced a 6% yield with the 84‐0‐0, 84‐5‐0, and 84‐20‐0 groups producing further modest increments. Overtraining produced a linear increase in yield, reaching 85% after 500 overtraining trials, a yield matching that produced by classes containing pictures as C stimuli (PIC). Thus, acquired discriminative functions and the overtraining of at least one function can account for class enhancement by meaningful stimuli.

Abstract We assessed the efficacy of, and preference for, accumulated access to reinforcers, which allows uninterrupted engagement with the reinforcers but imposes an inherent delay required to first complete the task. Experiment 1 compared rates of task completion in 4 individuals who had been diagnosed with intellectual disabilities when reinforcement was distributed (i.e., 30‐s access to the reinforcer delivered immediately after each response) and accumulated (i.e., 5‐min access to the reinforcer after completion of multiple consecutive responses). Accumulated reinforcement produced response rates that equaled or exceeded rates during distributed reinforcement for 3 participants. Experiment 2 used a concurrent‐chains schedule to examine preferences for each arrangement. All participants preferred delayed, accumulated access when the reinforcer was an activity. Three participants also preferred accumulated access to edible reinforcers. The collective results suggest that, despite the inherent delay, accumulated reinforcement is just as effective and is often preferred by learners over distributed reinforcement.

Se planeó un experimento para evaluar el efecto del intercambio de recursos y fuerza de trabajo en la elección entre contingencias no compartidas o contingencias compartidas de altruismo parcial con o sin ganancias diferenciales. Ocho díadas de estudiantes universitarios resolvieron rompecabezas en dos computadoras interconectadas en red (cuatro lo hicieron en el mismo cubículo y cuatro en cubículos distintos a fin de restringir la posibilidad de interacción verbal). En las condiciones experimentales, cada participante de la díada pudo observar la ejecución de su compañero y colocar sus piezas tanto en su rompecabezas como en el de su compañero. Después de las sesiones de línea base, las díadas se expusieron alternadamente a condiciones de consecuencias no diferenciales o diferenciales en una situación de altruismo parcial. En las fases de consecuencias no diferenciales los participantes obtuvieron un disco musical y en las de consecuencias diferenciales obtuvieron de cero a dos discos dependiendo del monto de puntos alcanzado. Los resultados sugieren que el intercambio de recursos y fuerza de trabajo así como el establecimiento de acuerdos entre los participantes favorecen la elección de contingencias compartidas de altruismo parcial, mientras que el carácter diferencial o no diferencial de las consecuencias no parece jugar un papel determinante. Se discuten los resultados en términos de las relaciones de intercambio involucradas y del papel de los factores situacionales y lingüísticos.