Avanzino Laura, Pelosin Elisa, Abbruzzese Giovanni, Bassolino Michela, Pozzo Thierry, Bove Marco
Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie.
Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, 16132 Genoa, Italy.
Cereb Cortex. 2014 Oct;24(10):2807-14. doi: 10.1093/cercor/bht139. Epub 2013 May 24.
Short-term upper limb disuse induces a hemispheric unbalance between the primary motor cortices (M1s). However, it is still unclear whether these changes are mainly attributable to the absence of voluntary movements or to the reduction of proprioceptive information. The goal of this work was to investigate the role of proprioception in modulating hemispheric balance during a short-term right arm immobilization. We evaluated the 2 M1s excitability and the interhemispheric inhibition (IHI) between M1s in 3 groups of healthy subjects. Two groups received during the immobilization a proprioceptive (P-VIB, 80 Hz) and tactile (T-VIB, 30 Hz) vibration to the right hand, respectively. Another group did not receive any conditioning sensory inputs (No-VIB). We found that in the No-VIB and in the T-VIB groups immobilization induced a decrease of left M1 excitability and IHI from left to right hemisphere and an increase of right M1 excitability and IHI from right to left hemisphere. Differently, only a partial decrease in left M1 excitability, no change in right M1 excitability and in IHI was observed in the P-VIB group. Our findings demonstrate that the maintenance of dynamic proprioceptive inputs in an immobilized arm through muscle vibration can prevent the hemispheric unbalance induced by short-term limb disuse.
短期上肢废用会导致初级运动皮层（M1）之间出现半球失衡。然而，这些变化主要是由于缺乏自主运动还是本体感觉信息减少仍不清楚。这项研究的目的是调查在短期右臂固定期间本体感觉在调节半球平衡中的作用。我们评估了三组健康受试者中两个M1的兴奋性以及M1之间的半球间抑制（IHI）。两组在固定期间分别接受了对右手的本体感觉振动（P-VIB，80赫兹）和触觉振动（T-VIB，30赫兹）。另一组未接受任何调节性感觉输入（无振动组）。我们发现，在无振动组和T-VIB组中，固定导致左M1兴奋性降低，从左半球到右半球的IHI降低，右M1兴奋性增加，从右半球到左半球的IHI增加。不同的是，在P-VIB组中，仅观察到左M1兴奋性部分降低，右M1兴奋性和IHI无变化。我们的研究结果表明，通过肌肉振动在固定手臂中维持动态本体感觉输入可以防止短期肢体废用引起的半球失衡。
