Voelcker-Rehage Claudia, Alberts Jay L
Jacobs centre for Lifelong Learning and Institutional Development, International University Bremen, Bremen, Germany.
Exp Brain Res. 2005 Sep;166(1):61-70. doi: 10.1007/s00221-005-2342-6. Epub 2005 Aug 12.
The aim of this study was to determine the effect of age on the modulation of forces produced by the digits and to determine the effects of practice on the control of these forces in young and older adults. Young (n = 14, 19-28 years) and old (n = 12, 67-75 years) adults used a precision grip to perform a variable force-tracking task (sine wave, 5-25% of maximum voluntary force) with their dominant hand. Participants performed 100 practice trials over 2 consecutive days. Results indicated that both groups improved accuracy of force tracking as a result of practice. Younger adults performed the task at a higher level in pre- and post-test conditions compared with older adults. Younger adults showed improvements in force control in force generation and release phases. Older adults reached performance levels comparable with younger adults' pre-test performance, but only after extended practice. In contrast to young adults, older adults' performance during the force release phases remained quite variable. These data suggest that older adults are impaired in the accurate release of grip force. Varied force release patterns that disrupt the precision of force modulation may contribute to older adults' diminished dexterous abilities.
本研究的目的是确定年龄对指力调节的影响，并确定练习对年轻人和老年人控制这些力量的影响。年轻成年人（n = 14，19 - 28岁）和年长成年人（n = 12，67 - 75岁）用优势手采用精确抓握方式执行可变力跟踪任务（正弦波，最大自主力的5 - 25%）。参与者在连续两天内进行100次练习试验。结果表明，两组都因练习而提高了力跟踪的准确性。与年长成年人相比，年轻成年人在测试前和测试后的条件下任务完成水平更高。年轻成年人在力产生和释放阶段的力控制方面有改善。年长成年人达到了与年轻成年人测试前表现相当的性能水平，但只是在长时间练习之后。与年轻成年人不同，年长成年人在力释放阶段的表现仍然相当不稳定。这些数据表明，年长成年人在准确释放握力方面存在缺陷。干扰力调节精度的不同力释放模式可能导致年长成年人灵巧能力下降。
