Neural Mechanisms of Compensating for Brain Damage

描述(由调查人员提供)：最可靠的结果之一 可存活的脑损伤的关键是动物经历了重大的行为变化 他们试图补偿自己的损伤。了解这些人的行为 变化与损伤引起的大脑变化相互作用可能对 了解神经和行为对脑损伤的适应。这项研究 将调查发生在心脏的部分失神经的可能性 局灶性皮质损伤后的连接区促进某些类型的学习 而这种学习背后的神经元变化。大鼠的行为能力 单侧损害感觉运动皮质前肢区(SMC) 用未受损的前肢获得熟练的运动任务最近 与完整的对应物相比，被发现是增强的。它是 假设运动学习的增强结果是轻微的 病变诱导的退行性事件促进了潜在的神经元变化 这种学习是在病变对面的初级运动皮质进行的。因为这些 损伤导致大鼠依赖于这条肢体，这提供了一个独特的模型 系统，以研究潜在的神经机制的发展 行为补偿。具体目标是：(1)进一步调查 SMC损毁对非损害者运动学习的促进作用 前肢，包括它对前肢先天偏好和损伤前的依赖 训练，(2)检验增强的学习与 损伤诱导的运动皮质神经可塑性改变，(3)决定 增强的学习和相关的神经可塑性改变对 损毁诱导的失神经和损毁诱导的行为改变，(4)确定 这些影响是否有一个敏感的伤后时间窗口？ 评估它们对功能结果的影响。这些研究将使用 灵敏的行为测量与定量光和 电子显微镜测量即刻早期基因表达的变化， 大鼠脑内树突状细胞骨架重构和突触连接的变化 运动皮质。预计结果或这些研究将具有重大意义 与康复工作的相关性。

DESCRIPTION (provided by investigator): One of the most reliable consequences of survivable brain damage is that animals undergo major behavioral changes as they attempt to compensate for their impairments. Knowing how these behavioral changes interact with injury-induced brain changes may be critical for understanding neural and behavioral adaptation to brain damage. This research will investigate the possibility that the partial denervation that occurs in a connected region after focal cortical injury promotes some types of learning and the neuronal changes underlying this learning. The ability of rats with unilateral damage to the forelimb region of the sensorimotor cortex (SMC) to acquire skilled motor tasks with the non-impaired forelimb has recently been found to be enhanced in comparison to their intact counterparts. It is hypothesized that the enhancement of motor learning results because mild lesion-induced degenerative events facilitate the neuronal changes underlying this learning in the primary motor cortex opposite the lesion. Because these lesions cause the rats to rely on this limb, this provides a unique model system to investigate neural mechanisms underlying the development of behavioral compensation. The specific goals are to: (1) further investigate the SMC lesion-induced enhancement of motor learning with the non-impaired forelimb, including its dependency on innate forelimb preferences and preinjury training, (2) test the hypothesis that the enhanced learning is linked to lesion-induced neuroplastic changes in the motor cortex, (3) determine the dependency of the enhanced learning and associated neuroplastic changes on lesion-induced denervation and lesion-induced behavioral changes, (4) determine whether there is a sensitive post-injury time window for these effects and (5) assess their implications for functional outcome. These studies will use sensitive behavioral measures in combination with quantitative light and electron microscopic measures of changes in immediate early gene expression, dendritic cytoskeletal restructuring and changes in synaptic connections in the motor cortex. The results or these studies are expected to be of major relevance to rehabilitation efforts.