Endo Takao, Kanda Hiroyuki, Hirota Masakazu, Morimoto Takeshi, Nishida Kohji, Fujikado Takashi
Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan.
Department of Applied Visual Science, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Graefes Arch Clin Exp Ophthalmol. 2016 May;254(5):947-56. doi: 10.1007/s00417-015-3253-2. Epub 2016 Jan 7.
To determine the accuracy of reaching movements with localization tests in subjects with simulated ultra-low vision, and to examine the effectiveness of auditory feedback training in improving the accuracy of the reaching movements.
Twenty-one subjects with simulated ultra-low vision and three patients with advanced retinitis pigmentosa (RP) were studied with the localization tester. The localization tester had white square targets with a visual angle of 10° that were projected randomly on a computer monitor screen. The subjects or RP patients were instructed to touch the center of the target. Each subject was tested 20 trials. The distance from the center of the target to the point where subjects touched, the deviation, was calculated automatically by the computer. We also examined the effect of auditory feedback on improving the accuracy of reaching movements.
The average angle of deviation in the subjects was not significantly correlated with visual acuity. The points touched by subjects with simulated low vision were located downward and horizontally toward the hand they used. They were condensed around the barycenter of the touched points (paired t tests; *p = 0.037). The touched points of the patients also deviated downward and condensed around the barycenter. The deviations decreased significantly with auditory feedback when trained over 100 trials.
The subjects with simulated ultra-low vision and the advanced RP patients had false orientations against the position of localized target systematically. An auditory feedback system may help to correct the false orientations for reaching movements in patients with very low vision.
确定在模拟超低视力受试者中进行定位测试时伸手动作的准确性，并检验听觉反馈训练在提高伸手动作准确性方面的有效性。
使用定位测试仪对21名模拟超低视力受试者和3名晚期视网膜色素变性（RP）患者进行研究。定位测试仪有视角为10°的白色方形目标，随机投射在电脑显示屏上。受试者或RP患者被要求触摸目标中心。每位受试者进行20次测试。电脑自动计算从目标中心到受试者触摸点的距离，即偏差。我们还研究了听觉反馈对提高伸手动作准确性的影响。
受试者的平均偏差角度与视力无显著相关性。模拟低视力受试者触摸的点位于其使用手的下方和水平方向。这些点集中在手触摸点的重心周围（配对t检验；*p = 0.037）。患者触摸的点也向下偏离并集中在重心周围。经过100多次训练后，听觉反馈使偏差显著减小。
模拟超低视力受试者和晚期RP患者对定位目标的位置存在系统性的错误定向。听觉反馈系统可能有助于纠正极低视力患者伸手动作中的错误定向。
