Differences In Obstacle Crossing Performances And The Associated Attentional Demands Between Elderly And Younger Adults

The walking patterns and the performances of stepping over obstacles change with age. This has implications for the problem of falls in elderly adults. PURPOSE: To investigate the differences in obstacle crossing performances and the associated attentional demands between elderly and younger adults under the single or dual task condition. METHODS: In total, twelve healthy elderly adults and fifteen healthy younger adults were included in this study. The sound operating system was used to provide a stimulus tone to the subject. Two in-series force platforms were used to record ground reaction forces. A three dimensional motion analysis system was used to collect the motion data. During reaction time (RT) test, a self-assembly radio telemetry handheld trigger was used to signal a response. Single-primary task (obstacle crossing alone), single- secondary task (hand button pressing alone), and dual-task (obstacle crossing plus hand button pressing tasks) were tested for each participant. RESULTS: The medial COM-COP inclination angles were significantly smaller in the elderly subjects than in younger subjects. However, no group differences were detected for peak anterior and posterior inclination angles. In addition, significant decreases in COM peak velocities in the A/P and M/L directions were detected in the elderly group when compared to the younger group during all tasks. The RT was significantly faster for all participants in the single- secondary task than for the dual-task condition. Task differences in reaction time were almost 100 ms for both the younger and elderly groups. During the dual-task test, the accuracy decreased for both the younger and elderly groups. In addition, the accuracy in the tone discrimination task was significantly higher for elderly participants in the single- secondary task condition than for the dual-task condition. However, no significant differences were detected for younger adults. CONCLUSIONS: Our study has verified that aging might delay early sensory processing and cognitive functioning. In addition, aging will also influence the gait strategy to maintain stability during obstacle crossing. This work was Supported by the National Science Council.