Toronto Rehabilitation Institute (University Health Network), Canada; Centre for Studies in Aging, Sunnybrook Health Sciences Centre, Canada.
Accid Anal Prev. 2013 Oct;59:407-14. doi: 10.1016/j.aap.2013.06.031. Epub 2013 Jul 1.
It appears that age-related changes in visual attention may impair ability to acquire the visuospatial information needed to grasp a handrail effectively in response to sudden loss of balance. This, in turn, may increase risk of falling. To counter this problem, we developed a proximity-triggered cueing system that provides a visual cue (flashing lights) and/or verbal cue ("attention use the handrail") to attract attention to the handrail. This study examined the effect of handrail cueing on grasping of the rail and associated gaze behavior in a large cohort (n=160) of independent and ambulatory older adults (age 64-80).
The handrail and cueing system was mounted on a large (2 m×6 m) motion platform configured to simulate a real-life environment. Subjects performed a daily-life task that required walking to the end of the platform, which was triggered to perturb balance by moving suddenly when they were adjacent to the rail. To prevent adaptation, each subject performed only one trial, and a deception was used to ensure that the perturbation was truly unexpected. Each subject was assigned to one of four cue conditions: visual, verbal, multimodal (visual-plus-verbal) or no cue.
Verbal cueing attracted overt visual attention to the handrail and markedly increased proactive grasping (prior to the onset of the balance perturbation) particularly when delivered unimodally. Subjects were otherwise much more likely to grasp the rail in reaction to the perturbation. A possible trend for visual cueing to improve the accuracy of these reactions was offset by adverse effects on reaction speed and on frequency of proactive grasping.
The results support the viability of using unimodal verbal cueing to reduce fall risk by increasing proactive handrail use. Conversely, they do not strongly support use of visual cueing (either alone or in combination with verbal cueing) and suggest that it may even have adverse effects. Further study is needed to evaluate effects of handrail cueing in a wide range of populations and real-life settings.
似乎与年龄相关的视觉注意力变化会损害有效获取扶手所需的视空间信息的能力，从而无法对突然失去平衡做出反应。这反过来又会增加跌倒的风险。为了解决这个问题，我们开发了一种接近触发式提示系统，该系统提供视觉提示（闪烁灯）和/或语音提示（“注意使用扶手”），以吸引注意力到扶手上。本研究在一个由 160 名独立且行动自如的老年人（年龄 64-80 岁）组成的大队列中，研究了扶手提示对抓握扶手和相关注视行为的影响。
扶手和提示系统安装在一个大型（2 m×6 m）运动平台上，该平台配置为模拟真实环境。受试者执行日常生活任务，需要走到平台的尽头，当他们靠近扶手时，平台会突然移动，从而触发平衡扰动。为了防止适应，每个受试者只进行一次试验，并使用欺骗手段确保扰动确实是意外的。每个受试者被分配到以下四种提示条件之一：视觉、语音、多模态（视觉加语音）或无提示。
语音提示将明显的视觉注意力吸引到手扶上，并显著增加了主动抓握（在平衡扰动发生之前），尤其是在单独提供语音提示时。否则，受试者更有可能在受到扰动后抓住扶手。视觉提示可能改善这些反应的准确性的趋势被反应速度和主动抓握频率的不利影响所抵消。
研究结果支持使用单一模式语音提示通过增加主动使用扶手来降低跌倒风险的可行性。相反，他们并不强烈支持使用视觉提示（单独使用或与语音提示结合使用），并表明它甚至可能产生不利影响。需要进一步研究以评估在广泛的人群和真实环境中使用扶手提示的效果。
