Análise dos efeitos do atraso e da probabilidade do reforço sobre a escolha em condições com esquemas concorrentes encadeados e simples

• Autor(a) principal: Matos, Daniel Carvalho de
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da PUC_SP
• Texto Completo: https://tede2.pucsp.br/handle/handle/16703
• topic: Escolha; Autocontrole; Reversão de preferência; Atraso do reforço; Probabilidade do reforço; Choice; Self-control; Preference reversal; Reinforcer delay; Reinforcer probability; CNPQ::CIENCIAS HUMANAS::PSICOLOGIA::PSICOLOGIA EXPERIMENTAL

The purpose of this research was to assess the effects of manipulating reinforcer delay and probability over the choices in simple and chained concurrent schedules and if these effects suggest similarities between these two reinforcer parameters. Four experiments were conducted. 12 psychology students from a private university served as participants, three for each experiment. The Experiments 1 and 2 involved choice trials between concurrent chained schedules with two links, with the manipulation of reinforcer magnitude and delay (Experiment 1) and reinforcer magnitude and probability (Experiment 2). In both experiments, the choice of component A, from the first link, produced, after T seconds (Experiment 1) or after a probability P (Experiment 2), the access to a new choice link between the components R1 with a small immediate reinforcer (Experiment 1) or a small and more probable reinforcer (Experiment 2) versus R2 with a larger delayed reinforcer (Experiment 1) or with a large and less probable reinforcer (Experiment 2). Still in the first link, in case the component B was chosen, after T seconds (Experiment 1) or a probability P (Experiment 2), there was a second link in which only one component was available: R2 with a large delayed reinforcer (Experiment 1) or with a large and less probable reinforcer (Experiment 2). As a result, first the participants went through selection conditions in which the larger reinforcer should be preferred over the small one (for both experiments); the immediate reinforcer should be preferred over the delayed one (Experiment 1) and the more probable reinforcer should be preferred over the less probable one (Experiment 2); the small immediate reinforcer should be preferred over the larger delayed reinforcer (Experiment 1) and the small and more probable reinforcer should be preferred over the larger and less probable one (Experiment 2). After this, all participants from both experiments went through conditions in which preference reversals, to the component with the larger and more delayed reinforcer (Experiment 1) or the component with the larger and less probable reinforcer (Experiment 2), were assessed. In Experiment 1, the variable time (T) between the two links was manipulated, involving 7.5 and 15 seconds. As result, the data revealed that preference reversal occurred for all the three participants from Experiment 1, considering that, only for participant P1, the reversal occurred when the time (T) between the two links was 7.5 seconds. Besides, for two of the participants (P1 and P3), most of the choices, on first link, were made on component B (alternative that was called the commitment choice according to the literature). In Experiment 2, preference reversal was assessed when the probability between the two links was 17%. The data revealed that reversal occurred, in the sense that most of the choices were made on the component with the larger and less probable reinforcer for all the three participants (P5, P6 and P7). Only for one of these participants (P6), the component B, from first link, was the most chosen one in two blocks of trials. Even though the data suggested relations with those that were obtained in Experiment 1, with the suggestion that reinforcer delay and probability share similar effects over the choices in chained concurrent schedules, there was a methodological problem in Experiment 2 that makes the comparison more difficult. The fact that the probability of the passage from the first to the second link was very low (17%) limited the number of trials in which participants had the chance to respond on second link. Consequently, the access to the reinforcers happened in only a few occasions. Experiments 3 and 4 involved choice trials between simple concurrent schedules with the manipulation of reinforcer magnitude and delay (Experiment 3) and reinforcer magnitude and probability (Experiment 4). After selection conditions similar to those from the two previous experiments, the participants went through a condition with concurrent FR / FR schedules (with a ratio that could vary from 10 to 80), in which the preference reversal was assessed. The data revealed that reversal occurred for all participants from Experiment 3 (P7, P8 and P9) with preference of the component with the larger and delayed reinforcer and the same happened for two of the participants from Experiment 4 (P11 and P12). The data suggested similarities between the reinforcer delay and probability parameters, considering their effects over choices in simple concurrent schedules. In both experiments other conditions (CRF, SigFR and FI) were conducted to assess if the response pattern produced by the FR would be changed, with most of the choices made on the other component with the small immediate reinforcer (Experiment 3) or the small and more probable reinforcer (Experiment 4). The data revealed that the change occurred only for two of the participants from Experiment 4 (P11 and P12), reinforcing the similarity with the data from a research conducted previously with pigeons as subjects