Arousal and Motor Performance in Older Adults

老年人的觉醒和运动表现

• 批准号: 6439851
• 负责人: ROGER M. ENOKA
• 金额: $ 7.27万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6439851
• 关键词: age difference; aging; anxiety; arousal; cognition; electrostimulus; emotions; functional ability; galvanic skin response; human middle age (35-64); human old age (65+); human subject; muscle contraction; neuromuscular function; patient oriented research; performance; physiology; psychological tests; psychology; psychophysiology; stimulus /response; stressor; young adult human (21-34)

The properties and function of the neuromuscular system change with advancing age. The effects on the performance capabilities of older adults are profound. We have found, for example, that finger movements are less steady in older adults compared with young adults. More recently, we have also demonstrated the impact of emotional state on neuromuscular function. We found that a stressor increased cognitive and physiological measures of arousal and impaired the ability of young men and women to exert a constant force during a submaximal pinch grip. It is likely that the same effect occurs in older adults. This led us to ask the question, does an increase in arousal further impair the steadiness of a submaximal pinch grip in older adults? Because baseline differences in steadiness are due to changes in the activation of muscle by nervous system, we hypothesize that an increase in arousal produces a greater deterioration of pinch-grip steadiness in older adults compared with young adults due the changes in motor unit function that occur with advancing age. We propose three specific aims to test this hypothesis: (1) to quantify the level of arousal evoked in young, middle-aged, and older adults in response to noxious stimulus using physiological and psychological measures; (2) to assess the fluctuations in force during a submaximal pinch grip performed by young, middle-aged, and older adults in the presence and absence of a noxious stimulus; (3) to examine the association between the changes in arousal fluctuations in pinch-grip force. We will quantify the moment-to-moment effect of the stressor on men and women with cognitive and physiological measures of arousal. The outcome variable will be the coefficient of variation for force during a submaximal pinch grip. We expect to find that the stress proposal will increase arousal to the same extent in all three groups of adults and that the impairment in steadiness will be proportional to the increase in arousal. These outcomes will result in a constant difference in steadiness between young and old adults, which will produce a much greater impairment in the simple motor task with an increase in arousal for the older adults. The findings will expand our understanding of the daily challenges experienced by older adults and will provide the foundation for a more extensive R01 application.

神经肌肉系统的特性和功能随着年龄的增长而变化。这对老年人的表现能力的影响是深远的。例如，我们发现，与年轻人相比，老年人的手指运动不太稳定。最近，我们还证明了情绪状态对神经肌肉功能的影响。我们发现，压力源会增加认知和生理唤醒指标，并损害年轻男女在次最大捏握过程中施加恒定力量的能力。同样的效果很可能发生在老年人身上。这让我们提出了一个问题：兴奋度的增加是否会进一步损害老年人次最大捏握的稳定性？由于稳定性的基线差异是由于神经系统激活肌肉的变化造成的，因此我们假设，与年轻人相比，由于运动单位功能发生变化，老年人的握力稳定性的增加会导致老年人的捏握稳定性更加恶化。随着年龄的增长。我们提出了三个具体目标来检验这一假设：（1）使用生理和心理测量来量化年轻人、中年人和老年人对有害刺激的反应所引起的唤醒水平； (2) 评估年轻人、中年人和老年人在存在或不存在有害刺激的情况下进行次最大捏握时力量的波动； （3）检查捏握力的唤醒波动变化之间的关联。我们将通过认知和生理唤醒指标来量化压力源对男性和女性的即时影响。结果变量将是次最大捏握过程中力的变异系数。我们预计会发现，压力提议会在所有三组成年人中以相同程度增加兴奋度，并且稳定性的​​损害将与兴奋度的增加成正比。这些结果将导致年轻人和老年人之间的稳定性存在持续差异，这将对简单运动任务产生更大的损害，同时老年人的觉醒程度也会增加。这些发现将扩大我们对老年人日常挑战的理解，并为更广泛的 R01 应用奠定基础。