As an aspect of hearing aid (HA) evaluation for the fitting, the psychoacoustic tests (speech discrimination test etc.) had been used. In the measure of intelligibility, however, only the correct response was taken into consideration and the other response distribution in a confusion matrix was ignored. So, this measure might not rspresent the full information in speech perception for the hearing impaired. On the other hand, the amount of transmitted information (TI) seemed to reflect the distribution pattern of the response in a confusion matrix. TI provided the information about the feature of response categories, consistency of performance over frequencies. Therefore, TI was thought to be better measure to evaluate the auditory capability of hearing impaired. The purpose of this study was to examine the relation between the sound level and TI, and thereby to consider whether or not the informational measure TI could be available for the volume setting of HA. Subjects were 9 sensori-neural hearing impaired children and 5 normal hearing adults. Sound stimuli, 14 phoneme syllables followed by /a/ were presented at each level of 10 dB step above S's average hearing threshold level. S was asked to identify the stimulus as one of the 14 letters printed on a sheet and write down it. TI was calculated by the formula for the SHANNON-WEAVER's informational measure. The result were as follows; (1) TI varied as a linear function of sound level to the extent of (0.6x+50) dB. Here, x was average hearing loss. (Fig. 1) (2) Above this level, neither TI increased nor decreased in most Ss. (Fig. 1) (3) The capacity of auditory system defined by maximum TI was decreased as the degree of hearing loss became severer. (Fig. 4) From the level of saturation point in TI curve, it was thought to be easy to estimate the sound level which was needed to make use of auditory perception efficiently. Therefore, it could be expected that TI gave the effective information about the decision of sound stimulus level. Thus, TI could be available for the setting of HA volume.

View full abstract

The purpose of this study was to compare the speech fluency and personality traits of spontaneously recovered stutterers with those of mild active stutterers. Subjects in two groups were selected from entering students at Y. University on the basis of the screening interview. Spontaneously recovered stutterers were fifteen male students who had been suffered from stuttering, but who had, in the absence of treatments, lately recovered. Mild active stutterers were sixteen male students whose disfluencies were not expressed more than recovered subjects', but who hoped to receive the proffessional service The main findings were as follow: 1. Though there was no significant difference in the neuroticism between the recovereds and the stutterers, an apparently significant difference was shown in the extroversion scores. Recovered stuttereres were significantly more extrovert than mild active stutterers. 2. Some differences were found in the adaptation effect with repeated readings of the same material. The repeated reading resulted in decreasing of disfluency in the recovereds with the greatest decrease on the second trial. It didn't result, however, in decreasing of disfluency in the stutterers whose disfluency was rather increased on the second one. 3. It was not concluded that the difference of adaptation effects was based on the difference of their personality traits.

View full abstract

The experimental works of Zigler and his associates on the behavior of the institutionalized retardate have indicated that his unique social life history, social deprivation, simultaneously produces a reluctance or wariness to interact with adults (negative reaction tendency) and a heightened motivation to do so (positive reaction tendency). This implies that the institutionalized retardate can maintain an affiliative relation with a supportive adult experimenter, when his negative reaction tendency has been preliminarily reduced by some experimental manipulation. In this study, various motivational conditions were set by the experimental manipulations of these reaction tendencies, and the effects of those conditions on the paired associate learning of the institutionalized retarded children and the institutionalized and the noninstitutionalized normal children, matched on MA, were examined. The results were as follows: (1) The motivational effects on the learning behavior of the institutionalized retardate were considerable. The reduction of his negative reaction tendency, which is produced by a preliminary success experience, has a facilitating effect on the successive learning behavior, and the effect is more heightened, when his positive reaction tendency is reduced by the experimenter's social reinforcement in the learning situation. But if his negative reaction tendency has not been preliminarily reduced, the reduction of his positive reaction tendency has no effect on his learning behavior. (2) The motivational effects on the learning behavior of the institutionalized normal were considerable, too, but not completely equal to those on the learning behavior of the institutionalized retardate. The preliminary reduction of his negative reaction tendency had a facilitating effect on his learning behavior, only when his positive reaction tendency was reduced by the experimenter's social reinforcement in the learning situation. In addition, the learning under the motivational condition in which both of these reaction tendencies were reduced was comparable with that under the motivational condition in which both of these reaction tendencies were not reduced. This result, not found in the case of the institutionalized retardate, implies the difference between the institutionalized retardate and normal in the ability to cope with social deprivation. (3) Motivational effects on the learning behavior of the noninstitutionalized normal were hardly found. He used an innerdirected learning strategy under the various motivational conditions. (4) The learning levels of the institutionalized retarded children, the institutionalized and the noninstitutionalized normal children, matched on MA, were significantly different from one another, when motivational conditions were not considered. The analysis of this result was attempted in terms of theories of the behavioral characteristics of retarded children: developmental positions and difference or defect positions.

View full abstract

Short-term memory is an area in which retarded individuals have long been regarded as deficient, but the explanations seeking to account for this deficiency have varied widely. Some have postulated a defect in biological makeup, whereas others have looked for ways in which they make poor use of essentially intact memory ability. Practically speaking. the distinction lies in the ease with which improvement can be brought about through training. Contemporary memory theories emphasize the latter. However, it must be recognized that measurement of memory ability is complex. It is determined by the amount acquired when the material is presented, the rate at which acquired material is forgotten, and the accuracy with which the material is retrieved. The bulk of the evidence shows that since both retarded people and normal people forget at the same rate, retarded person's memory deficit is due to an acquisition or a retrieval deficiency rather than to defective retention. The general consensus of opinion is that a characteristic feature of the memory deficiency is an inadequate spontaneous use of acquisition and/or retrieval strotegies in memory processes. In many of the memory tasks, efficient performance depends upon the spontaneous use of useful strategies in memory processes. As information is presented, the subject must manipulate and transter it in accordance with the nature of the task. In most cases, the best approach is to give careful attention to only appropriate parts of the material. In free-recall tasks, the associative clustering techniques can be of help. In paired-associate tasks, the optimal strategy is to add conceptual information in order to assist the memory. In some memory tasks, the subject should repeat the material to retain it in memory rather than let it be forgotten. In some of these tasks, the subject should also attempt to set aside previous materials. The failure to accomplish these strategies is a major source of the memory deficiencies shown by retarded subjects. Above all, a deficiency in the use of repetition is one of the most firmly established cognitive characteristics of retarded individuals. Primary sources of evidence that the retarded do not spontaneously rehearse have been the serial position effect (Ellis 1970) and pause patterns (Belmont & Butterfield 1969). Research in training methods has demonstrated that many deficiencies in retarded individuals are of production type. Retarded individuals can be trained in the use of memory strategies. There is, however, some evidence that the training may be limited in its ability to produce broad transfer. This problem can probably be overcome by very extensive training or overlearning.

View full abstract