Cortical microstimulation thresholds adjacent to sensorimotor cortex injury.
Cortical microstimulation thresholds adjacent to sensorimotor cortex injury.
复制标题
与感觉运动皮层损伤相邻的皮层微刺激阈值。
DOI：
10.1089/neu.1991.8.205
复制
发表时间：
1991
影响因子：
4.2
通讯作者：
Dail,WG
中科院分区：
文献类型：
--
作者：
Boyeson,MG;Feeney,DM;Dail,WG
单侧感觉运动（SM）皮层部分损伤后，最初严重的对侧运动功能障碍在损伤后几周内减轻。在这项研究中，提出了两个假设来解释皮层损伤后的行为功能的恢复进行了测试：（1）完整的皮层邻近的损伤重组，以接管功能的破坏区。(2)邻近或连接到受伤区域的完整SM皮层经历短暂的休克（神经连接不能），随着这种休克的消散，一些行为恢复发生。使用微刺激的成年大鼠的皮层，运动诱发的皮层损伤附近的地区进行了研究，在不同的时间后，底切裂伤，挫伤，或抽吸消融的SM皮层的一个区域。将刺激区域与未受伤的对照动物和对侧未受伤的半球进行比较。没有证据表明，任何重组的刺激运动反应在受伤的半球，即使在动物受伤后长达475天，表明其他机制的功能恢复。在离挫伤和撕裂伤一定距离的完整皮质中，引起运动的阈值显著升高，到伤后9-15天恢复正常。一些完整的后肢反应后，观察到挫伤后，在动物中不存在15天后的损伤，表明这种类型的创伤后的缓慢增长的病变。令人惊讶的是，在损伤后的任何时间，没有注意到消融损伤到腔的边缘的阈值升高，这表明边界附近的阈值变化可能与功能恢复无关。
The initial severe contralateral impairment of motor function after unilateral damage to a portion of sensorimotor (SM) cortex lessens within a few weeks after injury. In this study, two hypotheses proposed to explain recovery of behavioral function after cortical injury were tested: (1) Intact cortex adjacent to the injury reorganizes to take over the function of the destroyed area. (2) Intact SM cortex adjacent or connected to the injured area undergoes a transient shock (diaschisis), and as this dissipates, some behavioral recovery occurs. Using microstimulation of the cortex of the adult rat, movements evoked from areas near cortical injuries were studied at various times after undercut laceration, contusion, or suction ablation of an area of SM cortex. Stimulation areas were compared to those obtained from uninjured control animals and to the contralateral uninjured hemisphere. No evidence was obtained for any reorganization of stimulated motor responses in the injured hemisphere even in animals followed for as long as 475 days postinjury, suggesting other mechanisms underlying functional recovery. In intact cortex at some distance from contusion and laceration injuries, there was a marked elevation of thresholds to evoke movements that returned to normal by 9–15 days postinjury. Some intact hindlimb responses were observed after contusion injury that were absent in animals after 15 days postinjury, indicating a slow-growing lesion after this type of trauma. Surprisingly, no elevation in thresholds was noted for ablation injuries up to the edge of the cavity at any time postinjury, indicating that threshold changes near the boundary may be uncorrelated with functional recovery.