日本語の筆順における左右手の運筆機能の相違

Differences in Japanese handwriting function between left and right hands focusing on Japanese stroke order

要旨：本研究は右利き者の筆順に着目した際の左右手の運筆機能の相違を解明することを目的とした．20名の健常右利き男女を対象に，日本語の字体的特徴を含む図形4種に筆順条件を付加した課題を実施した．収集したデータは図形を要素に分解し，描画時間・筆圧・仰角・方位角・筆跡躍度・筆跡一致率に関する左右手データを比較した．結果，多くの要素で右手での筆圧が高く，仰角と方位角は要素毎に特徴的な左右差を示した．一方筆跡躍度と筆跡一致率に左右の有意差はなかった．今回筆順条件を加えたことで左右手の運筆機能の違いを示すことができた．非利き手では筆順の影響に伴う不自然な運動方向となり，筆圧がかかりにくいことが明らかとなった．

　This study focused on writing order with the purpose of investigating differences in the characteristics of moving the pen when writing with the left or right hand for right-handed people. Twenty healthy, right-handed subjects were asked to draw four types of figures containing stylistic features of characters of the Japanese writing system and were given instructions regarding stroke order. The collected data were broken down into elements, and the left- and right-hand data on drawing time, writing pressure, altitude angle, azimuth angle, jerk, and handwriting were compared. As a result, we found that the writing pressure with the right hand was high for many elements, and the altitude angle and azimuth angle showed characteristic left-right differences for each element. On the other hand, there were no significant differences in jerk and handwriting between the left and right hands.

By adding the stroke order condition, we were able to show the difference in the stroke function of the left and right hands, which clarified that the non-dominant hand has an unnatural movement direction due to the influence of the stroke order and has difficulty applying pressure.