RESUMEN
A novel paradigm is presented that was designed to mimic aspects of cue and response competition seen in humans in conflict procedures such as the Stroop task. Rats were trained simultaneously on two biconditional discrimination tasks, one auditory and one visual, in two different contexts: C1, in which A1:LP1-->R, A2:LP2-->R; and C2, in which V1:LP1-->R, V2:LP2-->R, where C1/C2 represent different training contexts (produced by different operant chambers), A1/A2 are different auditory cues, V1/V2 are different visual cues, LP1/LP2 are discrete operant responses, and R is reward. At test, rats received presentations of audiovisual compounds of these training stimuli in extinction. These compounds had dictated either the same (A1V1 or A2V2) or different (A1V2 or A2V1) responses during training: termed congruent and incongruent trials, respectively. Experiment 1 showed that following equal training on the two biconditional tasks, the contextual cues came to control responding to conflicting information provided by incongruent stimulus compounds such that animals responded according to the stimulus element previously trained in that test context. Experiment 2 demonstrated that differential training on the biconditional discriminations (with rats receiving training on the two discriminations in the ratio 3:1) resulted in greater interference from the overtrained task when animals were tested in the undertrained context. This finding is similar to the classic Stroop asymmetry seen in human performance whereby dominant word reading interferes with colour naming for incongruent colour-word compounds. Further analysis also revealed some evidence for a reverse Stroop effect in which the undertrained stimulus element interfered with performance on the overtrained task.
Asunto(s)
Conducta Animal , Conducta Competitiva , Desempeño Psicomotor , Animales , Señales (Psicología) , Masculino , RatasRESUMEN
In two experiments, participants were presented with pictures of different foods (A, B, C, D, X,) and learned which combinations resulted in an allergic reaction in a fictitious patient, Mr X. In Problem 1, when A or B (but not C or D) was combined with food X an allergic reaction occurred, and when C or D (but not A or B) was combined with Y an allergic reaction occurred. In Experiment 1, participants also received Problem 2 in which A, B, C, and D interacted with foods V and W either in the same way as X and Y, respectively, or in a different way. Participants performed more proficiently in the former than in the latter condition. In Experiment 2, after training on Problem 1, participants judged whether or not novel combinations of foods (e.g., AB, CD, AD, CB) would cause an allergic reaction in Mr X. They were no more likely to indicate that AB or CD would cause an allergic reaction than AD or CB, but made their judgements more rapidly and with greater confidence on AB and CD trials than on AD and CB trials. These results (1) indicate that shared representations come to be addressed by the components of similar compounds (e.g., AX and BX) that have predicted the same outcome (an allergic reaction), and (2) are inconsistent with standard, associative theories of learning, but (3) are consistent with findings from nonhuman animals and with a connectionist interpretation of these findings.
Asunto(s)
Asociación , Aprendizaje , Teoría Psicológica , Condicionamiento Psicológico , Retroalimentación , Humanos , Juicio , Distribución Aleatoria , Percepción VisualRESUMEN
In each of 4 experiments animals were given a structural discrimination task that involved visual patterns composed of identical features, but the spatial relations among the features were different for reinforced and nonreinforced trials. In Experiment 1 the stimuli were pairs of colored circles, and pigeons were required to discriminate between patterns that were the mirror image of each other. A related task was given to rats in Experiment 2. Subjects solved these discriminations. For Experiment 3, some pigeons were given a discrimination similar to that used in Experiment 1, which they solved, whereas others received a comparable task but with 3 colored circles present on every trial, which they failed to solve. The findings from Experiment 3 were replicated in Experiment 4 using different patterns. The results are difficult to explain by certain connectionist theories of discrimination learning, unless they are modified to take account of the way in which compound stimuli are structured.