An investigation of some theories of discrimination learning with respect to the performance of subnormal children

Abstract

Three theories of discrimination learning are reviewed, two of three being attention theories and one a mediating response theory. The attention theories are more compatible with the experimental results and although these two theories are basically similar, one theory offers a fuller explanation of existing results than the other. Accordingly results in this report are interpreted in terms of this theory.It has frequently been suggested that one of the factors characterizing the learning of the severely subnormal in their inability to attend to the relevant cues in the learning task. Several studies of animals have shown that problems which can be solved in terms of two dimensions tend to be learned solely in terms of one with little or nothing about the other; this has been called the "non-additivity of cues effect. The possibility of a "non-additivity of cues" effect in severely subnormal children is investigated.Experiments I and II show that a non-additivity of cues effect is obtained in some circumstances with severely subnormal children, and suggest that task difficulty may be an important variable. Experiment III confirms this result showing that the more difficult the task the more attention becomes restricted to one aspect of that task. This result is discussed in relation to theories of selective attention. Experiment III also indicates that if an easy dimension is paired with a difficult one pairing may aid learning of the difficult cue. Experiment IV investigates this possibility further and confirms it in some respects.The results are discussed in relation to theoretical models and with regard to their application to practical work with the severely subnormal.