Srygley Jennifer M, Mirelman Anat, Herman Talia, Giladi Nir, Hausdorff Jeffrey M
Movement Disorders Unit, Department of Neurology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.
Brain Res. 2009 Feb 9;1253:92-9. doi: 10.1016/j.brainres.2008.11.067. Epub 2008 Dec 3.
Age-associated changes in gait are exacerbated when another task is performed simultaneously. We quantified the converse, i.e., the effects of walking on cognitive abilities, and determined the role of aging and executive function (EF) in any observed changes. 276 healthy older adults and 52 healthy young adults performed three cognitive tasks, i.e., serial 7 and 3 subtractions and phoneme-monitoring, while sitting and again while walking. Among the elderly, walking decreased performance on serial 3 and 7 subtractions and the number of phonemes counted (p<0.0001), but enhanced content recall. In contrast, for the young adults, walking did not alter serial 3 subtractions, phoneme-monitoring or content recall, while serial 7 subtraction performance decreased during walking (p=0.047). Measures of EF explained the age-associated changes in performance of the cognitive task during walking. Findings in both young and old subjects underscore the idea that gait is attention-demanding and is not a purely motor task. Even young, healthy adults demonstrate decreased cognitive performance while walking, when the cognitive task is sufficiently difficult. Age-associated declines in EF apparently contribute to the difference in dual tasking abilities during walking between young and older adults.
当同时执行另一项任务时，与年龄相关的步态变化会加剧。我们对相反的情况进行了量化，即步行对认知能力的影响，并确定了衰老和执行功能（EF）在任何观察到的变化中的作用。276名健康老年人和52名健康年轻人在坐着和步行时分别执行了三项认知任务，即连续减7和减3以及音素监测。在老年人中，步行会降低连续减3和减7以及计数的音素数量的表现（p<0.0001），但会提高内容回忆能力。相比之下，对于年轻人来说，步行不会改变连续减3、音素监测或内容回忆能力，而连续减7的表现在步行时会下降（p=0.047）。执行功能的测量解释了步行过程中认知任务表现的年龄相关变化。年轻和老年受试者的研究结果都强调了这样一个观点，即步态需要注意力，而不是一项纯粹的运动任务。即使是年轻健康的成年人，当认知任务足够困难时，在步行时也会表现出认知能力下降。与年龄相关的执行功能下降显然导致了年轻人和老年人在步行时双重任务能力的差异。
