OBJECTIVE To study motor cortex plasticity after a period of training with a new prototype of bidirectional hand prosthesis in three left trans-radial amputees, correlating these changes with the modification of Phantom Limb Pain (PLP) in the same period. METHODS Each subject underwent a brain motor mapping with Transcranial Magnetic Stimulation (TMS) and PLP evaluation with questionnaires during a six-month training with a prototype of bidirectional hand prosthesis. RESULTS The baseline motor maps showed in all three amputees a smaller area of muscles representation of the amputated side compared to the intact limb. After training, there was a partial reversal of the baseline asymmetry. The two subjects affected by PLP experienced a statistically significant reduction of pain. CONCLUSIONS Two apparently opposite findings, the invasion of the "deafferented" cortex by neighbouring areas and the "persistence" of neural structures after amputation, could vary according to different target used for measurement. Our results do not support a correlation between PLP and motor cortical changes. SIGNIFICANCE The selection of the target and of the task is essential for studies investigating motor brain plasticity. This study boosts against a direct and unique role of motor cortical changes on PLP genesis.

中文翻译：

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手部假肢使用后的皮层可塑性：耳聋皮层“入侵”的假设总是正确的吗？

目的 研究三名左侧经桡骨截肢者在使用新型双向手部假肢训练一段时间后的运动皮层可塑性，将这些变化与同期幻肢痛 (PLP) 的改变相关联。方法 在使用双向假手原型进行为期六个月的培训期间，每位受试者都接受了经颅磁刺激 (TMS) 和 PLP 评估和问卷调查的大脑运动映射。结果 基线运动图显示，与完整肢体相比，所有三名截肢者的截肢侧肌肉面积较小。训练后，基线不对称出现了部分逆转。受 PLP 影响的两名受试者经历了统计学上显着的疼痛减轻。结论 两个明显相反的发现，邻近区域对“传入神经”皮层的侵袭和截肢后神经结构的“持久性”，可能因测量目标的不同而异。我们的结果不支持 PLP 和运动皮层变化之间的相关性。意义 目标和任务的选择对于研究运动大脑可塑性的研究至关重要。这项研究加强了运动皮层变化对 PLP 发生的直接和独特的作用。意义 目标和任务的选择对于研究运动大脑可塑性的研究至关重要。这项研究加强了运动皮层变化对 PLP 发生的直接和独特的作用。意义 目标和任务的选择对于研究运动大脑可塑性的研究至关重要。这项研究加强了运动皮层变化对 PLP 发生的直接和独特的作用。