Alberti Concetta F, Horowitz Todd, Bronstad P Matthew, Bowers Alex R
Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States of America.
Basic Biobehavioral and Psychological Sciences Branch, Behavioral Research Program Division of Cancer Control and Population Sciences, National Cancer Institute, Rockville, Maryland, United States of America.
PLoS One. 2014 Feb 18;9(2):e89381. doi: 10.1371/journal.pone.0089381. eCollection 2014.
The ability of visually impaired people to deploy attention effectively to maximize use of their residual vision in dynamic situations is fundamental to safe mobility. We conducted a pilot study to evaluate whether tests of dynamic attention (multiple object tracking; MOT) and static attention (Useful Field of View; UFOV) were predictive of the ability of people with central field loss (CFL) to detect pedestrian hazards in simulated driving.
11 people with bilateral CFL (visual acuity 20/30-20/200) and 11 age-similar normally-sighted drivers participated. Dynamic and static attention were evaluated with brief, computer-based MOT and UFOV tasks, respectively. Dependent variables were the log speed threshold for 60% correct identification of targets (MOT) and the increase in the presentation duration for 75% correct identification of a central target when a concurrent peripheral task was added (UFOV divided and selective attention subtests). Participants drove in a simulator and pressed the horn whenever they detected pedestrians that walked or ran toward the road. The dependent variable was the proportion of timely reactions (could have stopped in time to avoid a collision).
UFOV and MOT performance of CFL participants was poorer than that of controls, and the proportion of timely reactions was also lower (worse) (84% and 97%, respectively; p = 0.001). For CFL participants, higher proportions of timely reactions correlated significantly with higher (better) MOT speed thresholds (r = 0.73, p = 0.01), with better performance on the UFOV divided and selective attention subtests (r = -0.66 and -0.62, respectively, p<0.04), with better contrast sensitivity scores (r = 0.54, p = 0.08) and smaller scotomas (r = -0.60, p = 0.05).
Our results suggest that brief laboratory-based tests of visual attention may provide useful measures of functional visual ability of individuals with CFL relevant to more complex mobility tasks.
视障人士在动态环境中有效分配注意力以最大限度利用其残余视力的能力对于安全出行至关重要。我们进行了一项初步研究，以评估动态注意力测试（多目标跟踪；MOT）和静态注意力测试（有用视野；UFOV）是否能预测中心视野缺损（CFL）患者在模拟驾驶中检测行人危险的能力。
11名双侧CFL患者（视力20/30 - 20/200）和11名年龄相仿的视力正常驾驶员参与研究。分别通过基于计算机的简短MOT和UFOV任务评估动态和静态注意力。因变量分别为正确识别目标的比例达到60%时的对数速度阈值（MOT），以及在添加并发周边任务时正确识别中央目标的比例达到75%时呈现持续时间的增加量（UFOV的分散和选择性注意力子测试）。参与者在模拟器中驾驶，每当检测到有行人走向或跑向道路时按下喇叭。因变量是及时反应的比例（能够及时停车以避免碰撞）。
CFL参与者的UFOV和MOT表现比对照组差，及时反应的比例也更低（更差）（分别为84%和97%；p = 0.001）。对于CFL参与者，更高比例的及时反应与更高（更好）的MOT速度阈值显著相关（r = 0.73，p = 0.01），与UFOV分散和选择性注意力子测试中更好的表现相关（分别为r = -0.66和 -0.62，p < 0.04），与更好的对比敏感度得分相关（r = 0.54，p = 0.08）以及与更小的暗点相关（r = -0.60，p = 0.05）。
我们的结果表明，基于实验室的简短视觉注意力测试可能为CFL患者与更复杂出行任务相关的功能性视觉能力提供有用的测量方法。
