Effects on Environment Evaluation by Increasing Contrast Threshold in Visual Function of the Aged

本研究旨在探讨提高对比度阈值对老年人视功能环境评价的影响。以盛冈市44名70岁以上老人为被试，对16幅人行道图片进行分类心理实验。并对他们的视力（包括对比敏感度）、身体平衡、日常活动（计步）和其他生活状况（听和写）进行调查。分析对比阈值、MDS评估维度与日常生活活动能力之间的关系。研究老年人对比度阈值提高与日常活动的关系，最合适的指标是每天数步.活动量高的老年人对比阈值增加较少，以人行道宽度作为评价维度.老年人的对比度阈值在1000步/日和3300步/日的第一个时间点发生变化。适当的人行道宽度是必要的，以使老年人能够肯定地意识到视障人士的领先障碍。综合考虑，老年人视功能对比度阈值的提高，可能导致老年人潜意识活动空间的狭窄。

The Purpose of this study is to clarify the effects environment evaluation by increasing contrast threshold in visual function of the aged. Psychological experiment through classifying 16 sidewalk pictures was tried to the 44 aged persons over 70-years-old and living in Morioka City. And the investigation was made on their eyesight including contrast sensitivity, physical balance, daily activity by counting their walking steps, and other living conditions by hearing and writing down their words. The relation was analyzed among their contrast threshold, evaluation dimension obtained by MDS, and the degree of their daily living activity.The results based on the analysis were as follows ;1. The most proper index of daily activities to investigate the relation to the increasing contrast threshold in the Aged was counting steps/day.2. The aged with higher activity had less increasing contrast threshold and had the width of sidewalk as evaluation dimension.3. The increasing contrast threshold in the aged changed at the first point of 1000 steps/day and the second of 3300 steps/day.4. The proper enough width of sidewalks would be necessary for the aged to be affirmatively conscious of leading-blocks for the visual handicapped persons.5. Considering synthetically, it was suggested that the increasing contrast threshold in visual function of the aged would cause the stricture of subconscious activity space in the aged.