Effects of Mental Training on Voluntary Muscle Strength in Aging

描述(由申请者提供)：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)下行指令，并增强肌肉输出。这一发现在医学康复中有很大的应用价值，因为尽管对于许多认知健康的患者和患有肌肉无力的虚弱老年人来说，接受传统的力量训练是不安全或困难的，但他们可以利用大脑来加强肌肉。实施这类心理训练的两大障碍是调查人员无法直接监测受试者的心理过程，以及许多受试者，特别是认知能力减退的受试者(例如老年人)，在没有任何有关大脑活动的反馈的情况下，难以在精神上“强烈地”收缩肌肉。最近的研究表明，头皮脑电频率的功率与肌肉收缩的强度呈线性相关。此外，脑电振荡功率与预期(心理)肌肉收缩的强度成比例地增加。这些发现表明，脑电功率信号反映了大脑控制肌肉力量的活动，这为利用脑电频率功率作为监测心理训练质量和最大化结果的客观参数提供了可能性。我们的总体假设是，在给定的肌肉形态和协调性不变的情况下，力量的大小与驱动肌肉的大脑信号的大小直接相关；大脑皮质信号反馈的心理训练可以更有效地增强大脑信号，增加肌肉力量。目标1将通过监测脑电频率的功率来确定心理训练是否在允许老年人在没有这种反馈的情况下增加肌肉力量方面优于心理训练。目标2将研究潜在的神经机制，这些机制调节心理训练诱导的力量提高。假设有脑电反馈的心理训练组比没有脑电反馈的组表现出更大的皮质信号变化，获得更多的力量；神经适应的量将与力量的增加显著相关。这项研究将开发和评估一种新的强化肌肉的心理训练方法。该方法将使老年人和其他运动和认知能力下降的人有效地改善大脑功能，增加肌肉力量，而不需要接受举重等常规力量训练。

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.