AN EXPERIMENTAL STUDY ON "RIGIDITY" OF THE DEAF CHILD'S THINKING

Abstract

In order to verify the generally alleged "rigidity" of thinking in the deaf child the author carried out a comparative examination of deaf and normal school children. On the model of Luchins's test and with necessary modification of its principles for his purpose he prepared four series of test questions with Chinese characters as test materials, Each series contains five questions, which have a common feature (principle) to them, and in each question there are given six Chinese characters, of which one is different in its form from the others, which have a certain feature common to them. The examinee is required to find out the different one. (Fig. 2, 1). The subjects were of two groups, one from ordinary schools and the other from schools for the deaf, their ages ranging 10 to 16. They were all pupils in Germany and France and did not have any knowledge of Chinese characters (Table 1). In both groups the switch ratio, which is indicated by the ratio of the time needed for switching the principle to answer each question series, increased gradually in accordance with the increase of age of subjects, then declined (Table 13). In the normal group the ratio was highest in the pupils of 11 and 12 years of age, while in the deaf group the highest point was reached in the pupils of 13 and 14 years of age (Fig. 8). The disparity seems to mean that the deaf pupils are retarded two years in mental development. After reaching the highest point the ratio curve declined, as was just mentioned in both groups. The significance of ratio curve seems to be that every pupil, whether deaf or ncrmal, finds some difficulty in shifting principles in the transit period when he matures out of the concrete into the abstract way of thinking. But the rise of the ratio curve is to be interpreted to indicate that the pupil is gaining the ability to think in conceptual level. In the present investigation the two aspects of cognitve functions, perceptual and conceptual, were examined with subjects in sorting tasks without employing any experimental material, which facilitates conceptualization, so the two years's lagging of the deaf pupils in their development of abstract thinking should be attributed not to their limited command of language but to their undue dependence through deafness on visual perception. In comparison with the normal the deaf seem to rely on perceptualization more and longer than on conceptualization in abstract thinking in form of concrete operation.