Effects of Mental Training on Voluntary Muscle Strength in Aging

描述（由申请人提供）：越来越多的证据表明，用强烈肌肉收缩的心理意象训练可以增强（来自大脑的）下行命令并加强肌肉输出。这一发现在医疗康复中有很大的应用价值，因为尽管对许多认知健康的病人和体弱多病的肌肉无力的老年人来说，进行传统的力量训练是不安全或困难的，但对他们来说，用他们的思想来增强肌肉是可能的。实施这种类型的心理训练的两个主要障碍是研究人员无法直接监测受试者的心理过程，以及许多受试者，特别是那些认知能力下降的人（例如老年人），在没有任何有关大脑活动的反馈的情况下，难以在心理上“强烈”收缩肌肉。最近有研究表明，头皮脑电图频率的功率与肌肉收缩强度呈线性相关。此外，脑电图振荡功率随着预期（精神）肌肉收缩的强度成比例地增加。这些结果表明，脑电功率信号反映了控制肌肉力量的脑活动；这为利用脑电图频率功率作为监测心理训练质量和最大化训练效果的客观参数提供了可能。我们的总体假设是，在肌肉形态和协调性不变的给定受试者中，力量的大小与驱动肌肉的大脑信号的大小直接相关；大脑皮层信号反馈的心理训练可以更有效地增强大脑信号，增强肌肉力量。目的1将确定，在老年人中，通过监测脑电图频率的功率进行精神训练，是否比不进行这种反馈的精神训练更有利于肌肉力量的增加。目的2将研究潜在的神经机制，介导心理训练诱导的力量提高。假设有脑电图反馈的脑力训练组比无脑电图反馈的脑力训练组表现出更大的皮层信号变化和获得更多的力量；神经适应的数量将与强度的增加显著相关。本研究将开发和评估一种新的肌肉强化心理训练方法。该方法将使老年人和其他运动和认知能力下降的人能够有效地改善大脑功能，增加肌肉力量，而无需进行举重等传统力量训练。

DESCRIPTION (provided by applicant): Evidence is accumulating that training with mental imagery of strong muscle contractions enhances descending command (from the brain) and strengthens muscle output. This finding has substantial application in medical rehabilitation because although it is unsafe or difficult for many cognitively healthy patients and frail older adults who suffer muscle weakness to undergo conventional strength training, it is possible for them to use their mind to strengthen their muscles. Two major obstacles to the implementation of mental training of this type are the inability of investigators to monitor the mental processes of the subjects directly and the difficulty of many subjects, especially those with reduced cognitive ability (e.g., old people), to mentally contract a muscle "strongly" without any feedback about relevant brain activity. It has recently been shown that power of scalp EEG frequencies is linearly correlated to the intensity of muscle contraction. Furthermore, the EEG oscillation power increases proportionally with intensity of intended (mental) muscle contractions. These findings indicate that the EEG power signal reflects brain activities controlling muscle force; this offers the possibility of using the EEG frequency power as an objective parameter for monitoring quality of the mental training and maximizing the outcome result. Our overall hypothesis is that in given subjects with muscle morphology and coordination unchanged, the amount of strength is directly related to the magnitude of brain signal driving the muscle; mental training with the cortical signal feedback can more effectively enhance the brain signal and increase muscle strength. Aim 1 will determine whether mental training by monitoring the power of EEG frequency is superior in allowing gain in muscle strength to mental training without such feedback in older adults. Aim 2 will examine potential neural mechanisms that mediate mental training-induced strength improvements. It is hypothesized that the mental training group with the EEG feedback will exhibit greater cortical signal change and gain more strength than the group with no such EEG feedback; the amount of neural adaptation will correlate significantly with strength increases. PUBLIC HEALTH RELEVANCE This study will develop and evaluate a new mental training method for muscle strengthening. The method will enable older adults and others with reduced motor and cognitive abilities to effectively improve brain function and increase muscle strength without undergoing conventional strength training such as lifting heavy weights.