Optional shift learning as a function of age

Two experiments were conducted to examine the developmental mediation theory. In Exp. I, an optional shift problem was conducted with Ss from 4 to 18 years. In Exp. II, preschool children and junior college students were given a card-sorting task in order to identify S's dimensional preference, and the discrimination task was given only the form-preferred Ss. The results showed that (a) the percentage of intradimensional shift (ID) was higher than that of extradimensional shift (ED) throughout all the ages (Exp. I), (b) ID was easier than ED for both age groups (Exp. II), (c) in the preschool children, there was a relation between speed of learning and dimensional preference, but in the junior college students. There was no relation between them (Exp. II). The findings were discussed in the light of mediational and attentional theories.