ON THE POSITION CONDITIONED REFLEX IN MENTALLY RETARDED CHILDREN : THEIR EXCITABILITY AND INHIBITABILITY

Abstract

?1. The purpose of this report is to study the characteristics of the conditioned reflex in the mentally retarded children and to discuss about the porality of excitability and inhibitability. Each group consisted of 17 mentally retarded children (average IQ 50) and 13 normal school children. In this study, the results of a positive conditioned reflex of the GSR (galvanic skin reflex) in the mentally retarded children (experimental group) are compared with those given by the normal subjects. 2. The procedure of experiment is as follows; (1) CS-light flicker stimuli (25ps) and UCS-strong pure tone (500ps). (2) The experiment was divided into the following five stages. a) adaptation period b) UCS test period c) re-adaptation period d) reinforcement period e) extinction period In addition, three test trials are randomly placed in reinforcement period. 3. On the patterns of response-wave and also the changes of the orientating reflexes in adaptation period there were no apparent differences between two groups. 4. Concerning the percentage of the subjects who attained the conditioning-criterion, i. e., two responses out of 3 test trials, the control group showed a higher percentage than the experimental group. And the percentage of the subjects who attained the extinction-criterion was superior the control group. From these results, we conclude that in the mentally retarded children, it is more difficult to establish the conditioned reflex. 5. It was proved, however, that in the experimental group the magnitude of the response was larger than that of the control, and it clearly indicates the superiority of conditioning: especially the rise of the curve at the 3rd testtrial is suggesting us the firmly established conditioned reflex. It is suggested, therefore, that the mentally retarded children are more easily conditioned than the normal. 6. The mentally retarded children may be devided into three groups, concerning the establishment of the positive conditioned reflex: a) In the first group, belonging to the inhibitary type, conditioned reflex can not be entirely formed. b) In the second group, it is also imposible to form the conditioned reflex, but this group is different from the first group in its excitability, that is, the Ss in this second group shown more orienting reflex than the first. And c) in the last group, the conditioned reflex can be formed differently from that of the normal group.