Naito Eiichi, Roland Per E, Ehrsson H Henrik
Division of Human Brain Research, Department of Neuroscience, Karolinska Institute, Stockholm S171 77, Sweden.
Neuron. 2002 Dec 5;36(5):979-88. doi: 10.1016/s0896-6273(02)00980-7.
The primary motor cortex (MI) is regarded as the site for motor control. Occasional reports that MI neurons react to sensory stimuli have either been ignored or attributed to guidance of voluntary movements. Here, we show that MI activation is necessary for the somatic perception of movement of our limbs. We made use of an illusion: when the wrist tendon of one hand is vibrated, it is perceived as the hand moving. If the vibrated hand has skin contact with the other hand, it is perceived as both hands bending. Using fMRI and TMS, we show that the activation in MI controlling the nonvibrated hand is compulsory for the somatic perception of the hand movement. This novel function of MI contrasts with its traditional role as the executive locus of voluntary limb movement.
初级运动皮层（MI）被视为运动控制的部位。偶尔有报道称MI神经元对感觉刺激有反应，但这些报道要么被忽视，要么被归因于对自主运动的引导。在这里，我们表明MI激活对于我们肢体运动的躯体感知是必要的。我们利用了一种错觉：当一只手的腕部肌腱振动时，会被感知为手在移动。如果振动的手与另一只手有皮肤接触，则会被感知为两只手都在弯曲。使用功能磁共振成像（fMRI）和经颅磁刺激（TMS），我们表明控制未振动手的MI激活对于手部运动的躯体感知是必不可少的。MI的这一新功能与其作为自主肢体运动执行部位的传统作用形成了对比。
