Well-formedness Condition of the Japanese Sign Language syllable

2022 Fiscal Year Final Research Report

• Project/Area Number: 18H00671
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 02060:Linguistics-related
• Research Institution: Toyota Technological Institute
• Principal Investigator: Hara Daisuke 豊田工業大学, 工学部, 教授 (00329822)
• Co-Investigator(Kenkyū-buntansha): 三輪 誠 豊田工業大学, 工学(系)研究科(研究院), 准教授 (00529646)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 日本手話 / 音節 / 適格性 / 音素配列論 / 韻律外性 / 機械学習 / 決定木

Outline of Final Research Achievements

The previously used databases of well-formed and ill-formed syllables of Japanese Sign Language have been expanded and refined. It has been shown that the available positions for type 3 syllables are limited to the torso and neutral space at the height from below the chin to the waist, called the A-zone. With the aid of a decision tree machine learning algorithm, it has been showed that "hand postures" can function as factors causing ill-formed syllables. Extrametricality of the syllable onset in type 3 syllable formation has been demonstrated. It has been shown that only one underlying handshape is specified in the lexicon, even in syllables with handshape change, and the other handshape can be derived as an allophonic handshape. In Japanese Sign Language, it has been shown that syllable nuclei can be formed by "handshape-changing movements" and "palm-orientation-changing movements" as well as the larger movements.

Free Research Field

手話言語学

Academic Significance and Societal Importance of the Research Achievements

日本手話音節は、手型要素、位置要素、動き要素、その他いくつかの要素が組み合わさり形成される。その組み合わさり方には、音声言語の音素配列論同様に厳しい制約が課せられており、日本手話が決して身振りのような存在でないことが理解される。また韻律外性のような従来は音声言語にしか見られなかった現象が手話言語にもあることが示唆されたことは言語の普遍性の研究の一助となる。これらの知見は手話学習にも有効である。手話学習者は適格音節と不適格音節の判断がつきづらいため、音節構成要素の組み合わせに関する制約を学習の初期に提示・適用することにより手話音韻体系の効果的な学習を促進する。