The case of a young boy with verbal auditory agnosia (pure word diafness) was reported. Speech therapy was attempted for ten months. The findings obtained are as follows : 1) With improvement of auditory discrimination of onomatops, the threshold for the warble tone was lowered and reaction to environmental sounds was improved. 2) Study of auditory discrimination of onomatops was relatively successful, but study of auditory understanding of words was rather difficult. 3) Lip-reading was more difficult than expected. 4) Understanding words and two-word sentences written in hiragana and writing words were rather successful. 5) Preservation of inner language seemed rather good, yet not at normal level.
A home training program for language education was conducted on a young girl with severe hearing impairment over 90 dB who was born to deaf parents. She began to wear a hearing aid at the age of twelve months, while the training started when she was eighteen months old. A combined method of manual and oral communication was adopted for the language education because manual communication was used among members of the family in daily life. The girl began to learn manual communication and speech reading mainly through her parents. She began to express two-word sentences at the age of 25 months and multiword sentences at the age of 36 months using manual communication accompanied by spoken words. Consequently, she became able to communicate fluently with her deaf parents. The case reported here suggests that the combined method of manual and oral communication as tried in our clinic is very effective for language education of a deaf infant born to deaf parents, if the parents have enough language.
The perception of speech has been the subject of laboratory studies only about 30 years. Prior to that time, speech perception was not an important part of acoustical phonetics, nor was it prominent in studies on hearing. In these last 30 years, speech perception has become an important subject in acoustical phonetics, largely as a result of technological developments, but the theory and speculation about the speech-perception process has been too much separated from modern developments in psychophysics. In this paper, we shall review some of the bases for concepts like “categorical perception” and “listening in the speech mode”, and will show that a more parsimonious interpretation might be more generally auditory and psychophysical than “special” for speech. There do indeed appear to be special attributes of perception for speech, but they appear to be associated more with special circumstances of learning of speech sounds, as opposed to other sounds.