Yamamoto T, Xing J A, Katayama Y, Tsubokawa T, Hirayama T, Maejima S
Department of Neurological Surgery, Nihon University School of Medicine, Tokyo 173, Japan.
J Neurotrauma. 1990 Winter;7(4):247-56. doi: 10.1089/neu.1990.7.247.
The physiological characteristics of spinal cord responses recorded from the spinal epidural space of the cat to transcranial brain stimulation were studied, in comparison with the spinal cord responses to direct stimulation of the motor cortex or cerebellum. The conduction velocity of the initial wave of the responses to transcranial brain stimulation (122.3 +/- 16.3 m/sec mean +/- SD, n = 5) was much faster than the conduction velocity of the initial wave of the responses to motor cortex stimulation (68.3 +/- 14.7, n = 5) and similar to the conduction velocity of the initial wave of the responses to cerebellar stimulation (120.2 +/- 16.2, n = 5). Furthermore, the conduction velocity of any component in the subsequent polyphasic waves at any intensity was not similar to the conduction velocity of the initial wave of the responses to motor cortex stimulation. All components of the responses to motor cortex stimulation disappeared after intercollicular transection. In contrast, the initial wave of the responses to cerebellar stimulation and transcranial brain stimulation remained unaffected by intercollicular transection. The initial wave caused by anodal transcranial brain stimulation was eliminated by ablation of the cerebellum. However, cathodal transcranial brain stimulation sometimes can produce an initial wave that can be eliminated only by transection at the medullospinal junction. The initial wave of the responses to cerebellar stimulation was largest in amplitude when the vicinity of the dentate nucleus was stimulated. These results suggest that responses to activation of the cerebellum, rather than corticospinal neurons arising from the motor cortex, represent a major component of the spinal cord responses to transcranial brain stimulation in cats. The data obtained indicate that it is difficult to activate the motor cortex selectively by transcranial brain stimulation in cats.
研究了从猫的脊髓硬膜外间隙记录到的对经颅脑刺激的脊髓反应的生理特征，并与对运动皮层或小脑直接刺激的脊髓反应进行了比较。经颅脑刺激反应初始波的传导速度（平均±标准差为122.3±16.3米/秒，n = 5）比对运动皮层刺激反应初始波的传导速度（68.3±14.7，n = 5）快得多，且与对小脑刺激反应初始波的传导速度（120.2±16.2，n = 5）相似。此外，在任何强度下后续多相波中任何成分的传导速度都与对运动皮层刺激反应初始波的传导速度不同。在中脑间横断后，对运动皮层刺激的所有反应成分都消失了。相比之下，对小脑刺激和经颅脑刺激反应的初始波不受中脑间横断的影响。阳极经颅脑刺激引起的初始波在切除小脑后消失。然而，阴极经颅脑刺激有时可产生一个仅在延髓脊髓交界处横断才能消除的初始波。当刺激齿状核附近时，对小脑刺激反应的初始波幅度最大。这些结果表明，在猫中，对小脑激活的反应而非源自运动皮层的皮质脊髓神经元的反应，是脊髓对经颅脑刺激反应的主要组成部分。所获得的数据表明，在猫中通过经颅脑刺激选择性激活运动皮层是困难的。
