The development of speech fluency and the natural recovery of stuttering

2022 Fiscal Year Final Research Report

• Project/Area Number: 18K02785
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 09060:Special needs education-related
• Research Institution: Tokyo Gakugei University
• Principal Investigator: ITO Tomohiko 東京学芸大学, 教育学部, 名誉教授 (40159893)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: 幼児 / 発話 / 流暢性 / 発達 / 吃音 / 自然回復

Outline of Final Research Achievements

The acquisition of syntactic knowledge has been considered to be a crucial factor behind the onset and natural recovery of stuttering. However, it is not known which aspects of syntactic knowledge are essentially related to the onset and natural recovery of stuttering. This is a rare case study which includes data obtained before the onset of stuttering. The participant was a typically-developing Japanese child. We focused on sentences with verb-argument structure as an index of the development of sentence production. The period of a rapid increase in the production of verb-argument sentences corresponds not only with the period of the onset of stuttering but also with a high frequency in stuttering. The period of stable production in verb-argument sentences corresponds with both a decrease in stuttering as well as with its complete disappearance. These results suggest that the syntax spurt is closely related to the onset and natural recovery of stuttering.

Free Research Field

言語障害学　心理言語学

Academic Significance and Societal Importance of the Research Achievements

本研究は吃音が発生する前からのデータを含むという点で極めてまれなケース研究であり、動詞と項からなる文に焦点をあてた吃音の発生および自然回復に関する縦断研究である点でユニークなものである。本研究の結果、吃音が自然回復する幼児においては吃音が発生するのは動詞と項からなる文が急増し始める時期であり、吃音が減少するのはこの文が安定した割合で産出される時期であることが明らかになった。この結果は解明が待たれている持続する吃音の解明に不可欠な情報を提供するものである。