Filippi Guido M, Rodio Angelo, Fattorini Luigi, Faralli Mario, Ricci Giampietro, Pettorossi Vito E
Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy.
Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy.
Front Neurosci. 2023 Feb 22;17:1112232. doi: 10.3389/fnins.2023.1112232. eCollection 2023.
Repetitive focal vibrations can induce positive and persistent after-effects. There is still no satisfactory interpretation of the underlying mechanisms. A rationale, which can provide consistency among different results, is highly desirable to guide both the use of the application and future research. To date, interpretive models are formulated to justify the results, depending on the specific protocol adopted. Indeed, protocol parameters, such as stimulus intensity and frequency, intervention time and administration period, are variable among different studies. However, in this article, we have identified features of the protocols that may allow us to suggest a possible common mechanism underlying the effectiveness of focal vibration under different physiologic and pathologic conditions. Since repetitive focal muscle vibration induces powerful and prolonged activation of muscle proprioceptors, we hypothesize that this intense activation generates adaptive synaptic changes along sensory and motor circuits. This may lead to long-term synaptic potentiation in the central network, inducing an enhancement of the learning capability. The plastic event could increase proprioceptive discriminative ability and accuracy of the spatial reference frame and, consequently, improve motor planning and execution for different motor functions and in the presence of different motor dysfunctions. The proposed mechanism may explain the surprising and sometimes particularly rapid improvements in motor execution in healthy and diseased individuals, regardless of specific physical training. This hypothetic mechanism may require experimental evidence and could lead to extend and adapt the application of the "learning without training" paradigms to other functional and recovery needs.
重复性局部振动可诱发积极且持久的后效应。对于其潜在机制仍没有令人满意的解释。非常需要一个能在不同结果之间提供一致性的理论依据，以指导该应用的使用和未来研究。迄今为止，解释模型是根据所采用的特定方案来制定以证明结果的合理性。实际上，不同研究之间方案参数，如刺激强度和频率、干预时间和给药周期等都是可变的。然而，在本文中，我们已经确定了方案的一些特征，这些特征可能使我们能够提出一个在不同生理和病理条件下局部振动有效性背后可能的共同机制。由于重复性局部肌肉振动会诱发肌肉本体感受器强烈且持久的激活，我们假设这种强烈激活会沿着感觉和运动回路产生适应性突触变化。这可能会导致中枢网络中的长期突触增强，从而提高学习能力。这种可塑性事件可能会提高本体感觉辨别能力和空间参照系的准确性，进而改善不同运动功能以及存在不同运动功能障碍时的运动计划和执行。所提出的机制可能解释了健康个体和患病个体在运动执行方面令人惊讶且有时特别迅速的改善，而无需特定的体育训练。这种假设机制可能需要实验证据，并可能导致将“无训练学习”范式的应用扩展并适应于其他功能和恢复需求。
