FAST ELECTRICAL OSCILLATIONS IN SOMATOSENSORY CORTEX

也许是最古老、最广为人知、最不为人所知的 人脑的电现象是疾病的，在健康的是 其特点是电振荡幅度大。最近， 在理解两国关系方面取得了重大进展 大脑振荡和大脑功能之间的关系。大脑皮质 高频伽马频段(约40赫兹)的振荡似乎 在信息处理的时间同步中发挥作用 在感觉皮质中。然而，它们的功能意义和作用机制。 神经发生仍然是一个有很多猜测和争议的问题。 在本实验系列中，这两个问题都将通过 执行二维分布的高分辨率映射 在行星表面诱发和自发的伽马振荡 经络电极阵列在大鼠触觉/桶状皮质中的作用 通过将这些时空地图与并发记录进行比较 在体感丘脑的特异核和非特异核中进行。 先前在听觉系统中获得的与丘脑有关的结果 大脑皮层伽马振荡的调制，将首先外推 到躯体感觉系统，建立结构和功能 应该有力地支持或驳斥关于 不同的丘脑系统在发育过程中的参与 大脑皮层伽马振荡的调制。第二，有可能 相互连接的丘脑皮质回路内的同步 在此期间，将研究伽马振荡。丘脑皮质触觉 在单个皮质柱水平上的相互作用。空间上的 和振动管中伽马振荡的时间特性 场，以及可能的丘脑皮质同步，将在 未被麻醉的无拘无束的大鼠散发着活跃的触觉 辨别任务。 这些实验将为理解 啮齿动物伽马振荡的神经发生及其相互关系 到潜在的解剖学和突触神经支配，弥合了 我们对单细胞特性和响应之间的理解 更大的多突触神经系统的特性。这些实验 也将为类似的传导提供一个更加有限的起点 在人体上进行研究，这是我们研究计划的长期目标。

Perhaps the oldest, most widely recognized, and least understood electrical phenomena of the human brain is sickness and in health are its characteristic large amplitude electrical oscillations. Recently, there has been a major advance towards understanding the relationship between brain oscillations and brain function. Electrocortical oscillations in the high frequency gamma band (approx.40 Hz) appear to play a role in the temporal synchronization of information processing in sensory cortex. Yet, their functional significance and mechanism of neurogenesis is still a matter of much speculation and controversy. In this experimental series, both of these issues will be addressed by performing high resolution mapping of the two dimensional distribution of evoked and spontaneous gamma oscillation on the surface of vibrissa/barrel cortex in the rat using 64 channel electrode arrays, and by comparing these spatiotemporal maps to concurrent recordings performed in specific and nonspecific nuclei of somatosensory thalamus. Results previously obtained in the auditory system, concerning thalamic modulation of cortical gamma oscillations, will first be extrapolated to the somatosensory system, to establish structural and functional analogies that should strongly support or refute hypothesis about the participation of distinct thalamic systems in the generation or modulation of cortical gamma oscillations. Second, possible synchronization within reciprocally connected thalamocortical circuits during gamma oscillation will be studied. The vibrissa thalamocortical interactions at the level of individual cortical columns. The spatial and temporal properties of gamma oscillation in the vibrissa/barrel field, and possible thalamocortical synchronization, will be studied in the unanesthetized and unrestrained rat perfuming an active tactile discrimination task. These experiments would provide a basis for understanding the neurogenesis of gamma oscillations in the rodent, and their relationship to underlying anatomy and synaptic innervation, bridging a major gap in our understanding between single cell properties and the response properties of larger multi-synaptic neural systems. These experiments will also provide a starting point for conduction similar more limited studies in humans, the long range goal of our research program.