シングルケーススタディ；左側無視患者に対する左側方向への注意喚起を促す指示の効果の検討

Single case study; the effect of calling attention toward left space in a patient with unilateral spatial neglect after brain injury

要旨：病識不全を示した42歳の左側無視患者に対し，無視の指摘と左側空間への注意の喚起が左側無視の改善をもたらすかどうかを確認するため，ABA'方式のシングルケーススタディを実施した．従属変数は珠算能力検定2級練習問題における左端数字の見落とし数，正解数，所要時間，誤操作数とした．その結果，介入によって左側の見落とし数は減少することが確認されたが，その効果は定着しにくいことがわかった．また，電卓の誤操作など左側無視以外の要因による計算ミスが増加したこともわかった．半側無視に対する病識不全は一貫して変わらなかった．これらの原因として，反復的な欠点の指摘が心理的ストレスを誘発していた可能性，注意喚起の方法が患者からみて受動的なものであったことなどが考えられた．

　We reported the effect of calling attention toward the left space in a 42-year-old male patient with unilateral spatial neglect after brain injury. The patient failed to solve numerical calculations while using an electronic calculator because of neglecting digits on the left side. We hypothesized that this left -sided neglect would be ameliorated if the patient was encouraged to attend toward the left space prior to each task and was then informed of the result of performance after each task. A single case research design, type A-B-A', was used. Baseline, intervention, and after-baseline phases each consisted of ten sessions. The number of the neglecting digit on the left side, the correct answer, the time required, and the error number without unilateral neglect were measured at each session. The results demonstrated that the number of neglected digits decreased during the intervention phase, but the effect did not sustain itself. The error numbers without unilateral neglect increased during the intervention phase. Furthermore, his unawareness for unilateral neglect was not changed by the intervention in the study. The effect of calling attention used in this study was insufficient on the durability and unawareness for unilateral neglect, although it was effective on the decrease in neglecting digits on the left side. We thought that one possibility was mental stress, which evoked his defect repeatedly. Alternatively, our intervention, which consisted only of orally calling the patient's attention toward the left hemi-space, might have caused the insufficiency.