Overtraining, extinction and shift in discrimination learning in children

Abstract

The purpose of the present experiment was to ask whether the ease of post-shift discrimination learning after overtraining was related to the rate of extinction of original responses or to the mediating verbal or attentional process to the relevant dimension, as was proposed by twostage theorists of discrimination learning (e.g., Kendler & Kendler, 1962; Mackintosh, 1965).A 2×2 factorial design was used, with two degrees of original discrimination learning and two types of shift (reversal and nonreversal). In each of the four groups, extinction trials were inserted between original and shift problems. The Ss were young children ranged in age from four to six years, who were divided into each of four groups equating in age and sex. They were trained on a twodimensional (color and form), simultaneous discrimination task either to a criterion of nine correct responses out of 10 successive trials or to additional 30 overtraining trials after the criterion. Then, the Ss were subjected to extinction of the original responses until the successive perseverative responses to S+ were extinguished and additional four extinction trials were further given. Shift discrimination was continued without further instructions to a criterion of nine correct responses out of 10 successive trials. The correct responses were reinforced by saying “Hit”, but no information was given after the incorrect responses under both discrimination learnings. In the extinction phase no information was given after each response.The main findings were summarized as follows;(a) Performances during the extinction trials were not influenced by the overtraining of original discrimination (Table 2).(b) No significant correlation was found between rate of extinction and ease of shift discrimination.(c) No significant effect of overtraining was found in case of reversal shift, while nonreversal shift was hindered by the overtraining of original discrimination (Table 3).(d) Fast learners in the original discrimination extinguished their original esponses more slowly than slow learners.(e) Reversal shift was faster than nonreversal shift for the fast learners, but a difference in rate of both shifts was negligible for the slow learners (Table 4).The findings were discussed with reference to two-stage theories of discrimination learning, especially with respect to the Kendlers' mediating response theory and the Mackintosh's attention theory.