Alstermark B, Górska T, Johannisson T, Lundberg A
Neurosci Res. 1986 Jul;3(5):457-61. doi: 10.1016/0168-0102(86)90038-6.
Forelimb target-reaching in cats with a transection at C5/6 of the cortico- and rubrospinal tracts is known to depend on C3-C4 propriospinal neurones (PNs). An additional lesion transecting the dorsal column (DC) in C5/6, caudal to the C3-C4 PNs, gave pronounced hypermetria in lifting and protraction during target-reaching. If the additional DC lesion instead was made in C2, rostral to the C3-C4 PNs, there was only small hypermetria in lifting and none in protraction. It is postulated that the hypermetria after the C5/6 DC lesion is due to interruption of the inhibitory pathway from the forelimb to the C3-C4 PNs. It is suggested that feedback control from the forelimb of the premotoneurones is an integral part of the control of normal target-reaching.
已知在皮质脊髓束和红核脊髓束于C5/6水平横断的猫中，前肢够取目标的动作依赖于C3 - C4节段脊髓固有神经元（PNs）。在C5/6水平、C3 - C4 PNs尾侧横断背柱（DC）的额外损伤，会在目标够取过程中的抬起和前伸动作中产生明显的动作过度现象。如果额外的DC损伤是在C2水平、C3 - C4 PNs头侧进行的，那么在抬起动作中仅有轻微的动作过度，在前伸动作中则没有。据推测，C5/6 DC损伤后的动作过度是由于从前肢到C3 - C4 PNs的抑制性通路中断所致。有人提出，运动前神经元前肢的反馈控制是正常目标够取控制的一个组成部分。
