幼児のことばの発達（8）—1精神発達遅滞児のことばの発達（第2報）

LONGITUDINAL STUDY ON SPEECH DEVELOPMENT OF A MENTALLY RETARDED GIRL: REPORT (2)

　Ⅰ．緒言

　精神発達遅滞の1女児のことばの発達を，1歳2カ月から追跡してきた。4歳0カ月までの経過については既に報告した^2）。この時期までの発達をみると，3歳以後，語彙数，有意味語を用いた発話の数，文形態をとる発話の数などは増加したが，発話の90％以上が本人の側から一方的に発されたもので，他者からの話しかけに応じるということはきわめて少ないなど，正常児の発達と比較して，著しい違いがあることを指摘した。本児は現在7歳6カ月になつたので，4歳以後の発達の経過を報告しご参考に供したい。

　Observations on the development of speech of a mentally retarded girl were continued from her 1 year and 2 months to 7 years and 5 months. Since the developmental processes up to 4 years had previously been reported this paper dealt with those from 4 years on through 7.

　One-hour tape recordings were collected by an examiner visiting her home once every month on approximately the same days around her birthday. The recordings were then listened carefully and the utterances both of the child and of the people around her were transcribed word for word. The transcribed data were used for later analyses. Some results were as follows:

　The meaningful utterances increased rapidly from 3 years on till 6:0, at which time they reached a plateau. The vocabulary increased gradually up to 5 : 5 and more rapidly afterwards till 6:3, from which time on not much increase was observed.

　Though the vocaLulary and meaningful utterances increased greatly, and sentences got longer with better grammatical constructions, communication skills did not develop along with them. In contrast with a great number of spontaneous utterances, responses to what she was talked occurred scarcely until 5:5, and though they slowly increased afterwards they were returned only at 40% of the times of their requirements even at 7:5. Her utterances, though meaningful in the sense that they were constructed by meaningful words, were often irrelevant to the situations. Not a small number of negative utterances were directly followed by affirmative ones on one subject. Preceding ideas and expressions persevarated out of context. Her real intentions of her utterances, if any, were not communicable to the listener at about half of the times even at 7:5.

　It was discussed that the speech development of this girl could not be explained by merely slowing down the normal developmental proces-ses.