紙教科書とデジタル教科書の読みの際の眼球運動の比較 : 読みの困難度に着目した予備的検討

紙の教科書を音読する条件（紙音読）、デジタル教科書を音読する条件（デ音読）、デジタル教科書を音声で読み上げる条件（デ読上）のそれぞれにおいて読み困難の有無が平均停留時間及び停留回数といった眼球運動に与える影響を検討した。対象は小学３年から６年の読み困難なしの19名と読み困難ありの６名であった。
実験参加者は光村図書の道徳と国語の紙の教科書及びデジタル教科書を用い３つの条件で読むことを依頼された。眼球運動はTobii Glass 3 （サンプリングレート120Hz）で収集された。マッピング可能であった489ページを対象に分析を行った。小学３・４年生を中学年群、５・６年生を高学年群に群分けした。文字の範囲では、中学年群と、高学年群の両方で紙音読条件において読み困難「なし」よりも「あり」の平均停留時間が有意に長かった（p < .05）。紙の教科書において読み困難「あり」は「なし」よりも停留時間が延長した。デ音読条件、デ読上条件において２群間の平均停留時間に有意差はなかった。停留時間の差異が小さくなることは、読み困難「あり」の読書中の眼球運動が読み困難「なし」に接近していることを意味している。
今回は実物の紙とデジタルの教科書を利用し、普段の読書に近い自由な条件で検討したため、これ以上の精密な検討はできないが、デジタル教科書が読み困難「あり」の児童の読みに与える研究に示唆を与える結果となった。

We have studied the effects of having a reading difficulty on eye movement behaviors such as average duration and number of fixations in three different reading conditions: AP, where participants read paper textbooks aloud; AD, where they read digital textbooks aloud; and SD, where they read digital textbooks silently and follow where the synthesized voice is reading with their eyes. The subjects of this study were 19 skilled readers and six poor readers in the third to sixth grade of primary school. The participants were asked to read textbooks on moral education and Japanese published by Mitsumura Tosho Publishing Co., Ltd. in paper and digital forms, in the above three conditions. Eye movement information was sampled by Tobii Glass 3 with the sampling rate of 120Hz. We were able to map 489 textbook pages and analyzed the eye movements of these pages. Participants were categorized into two groups: a middle-year group with third and fourth grade students, and an older-year group with fifth and sixth grade students. The smaller the difference in duration, the more similar the eye movement of poor readers is to that of skilled readers. In both groups, poor readers showed significantly longer average duration of fixation (p<.05) under the AP condition. In other words, poor readers showed a longer duration of fixation on text than skilled readers did when reading paper textbooks. No significant difference was recorded for the average duration of fixation between conditions AD and SD. For this study, we used real textbooks and allowed participants to read in conditions similar to their normal reading styles, so we cannot investigate more precisely than the above at this time. The results provide an indication that digital textbooks may have positive effects on poor readers’ reading.