Department of Kinesiology, Seattle University, Seattle, Washington, United States.
Department of Rehabilitation Sciences & Technology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, United States.
J Neurophysiol. 2023 Nov 1;130(5):1309-1320. doi: 10.1152/jn.00486.2022. Epub 2023 Oct 25.
Greater heterogeneity exists in older adults relative to young adults when performing highly skilled manual tasks. The purpose of this study was to assess the influence of visual feedback and attentional demand on visual strategy during a submaximal force-steadiness task in young and older adults. Eye movements of 21 young (age 20-38 yr; 11 females, 10 males) and 21 older (age 65-90 yr; 11 females, 10 males) adults were recorded during a pinch force-steadiness task while viewing feedback with higher and lower gain and while performing a visuospatial task. For the visuospatial task, participants imagined a star moving around four boxes and reported the final location after a series of directions. Performance on standardized tests of attention was measured. All participants gazed near the target line and made left-to-right saccadic eye movements during the force-steadiness tasks without the visuospatial task. Older adults made fewer saccades than young adults (21.0 ± 2.9 and 23.6 ± 4.4 saccades, respectively) and with higher versus lower gain (20.9 ± 4.0 and 23.7 ± 3.5 saccades, respectively). Most participants used the same visual strategy when performing the visuospatial task though seven older adults used an altered strategy; gaze did not stay near the target line nor travel exclusively left to right. Performance on standardized measures of attention was impaired in this subset compared with older adults who did not use the altered visual strategy. Results indicate that visual feedback influences visual strategy and reveals unique eye movements in some older adults when allocating attention across tasks. This study contributes novel findings of age-related changes in visual strategy and associations with attentional deficits during hand motor tasks. Older adults used fewer saccades than young adults and with higher versus lower gain visual feedback during a force-steadiness task. A subset of older adults used an altered visual strategy when allocating attention across multiple tasks. Given that this subset demonstrated attentional deficits, the altered visual strategy could serve to indicate motor and/or cognitive impairments.
在执行高技能手动任务时，老年人比年轻人表现出更大的异质性。本研究旨在评估视觉反馈和注意力需求对年轻和老年成年人在次最大力稳定任务中视觉策略的影响。在一项捏力稳定性任务中，当参与者观看具有较高和较低增益的反馈以及执行视空间任务时，记录了 21 名年轻（年龄 20-38 岁；11 名女性，10 名男性）和 21 名老年（年龄 65-90 岁；11 名女性，10 名男性）成年人的眼动。对于视空间任务，参与者想象一颗星在四个盒子周围移动，并在一系列方向后报告最终位置。测量了注意力的标准化测试表现。所有参与者在力稳定任务期间凝视目标线附近，并进行从左到右的扫视眼动，而无需进行视空间任务。与年轻人相比，老年人的扫视次数更少（分别为 21.0 ± 2.9 和 23.6 ± 4.4 次扫视），且增益较高（分别为 20.9 ± 4.0 和 23.7 ± 3.5 次扫视）。大多数参与者在执行视空间任务时使用相同的视觉策略，尽管有 7 名老年人使用了改变的策略；注视没有停留在目标线附近，也没有专门从左到右移动。与没有使用改变的视觉策略的老年人相比，这一组的注意力标准化测试表现受损。结果表明，视觉反馈会影响视觉策略，并在一些老年人在分配注意力时揭示独特的眼动。这项研究为手部运动任务中与注意力缺陷相关的视觉策略的年龄相关变化及其关联提供了新的发现。在力稳定任务中，与年轻人相比，老年人的扫视次数更少，并且增益较高（分别为 21.0 ± 2.9 和 23.6 ± 4.4 次扫视）。与年轻人相比，增益较高（分别为 20.9 ± 4.0 和 23.7 ± 3.5 次扫视）。在分配注意力时，一些老年人使用了改变的视觉策略。鉴于这一组表现出注意力缺陷，改变的视觉策略可能表明运动和/或认知障碍。
