NEURAL CONTROL OF VISUALLY GUIDED EYE MOVEMENTS

描述：几个神经系统有助于控制视觉 引导的快速眼球运动包括枕骨的部分， 顶叶额叶和上级丘皮质 所涉及的区域可分为两个主要系统，前和后系统。 后面。前系统由前眼组成 场和背内侧额叶皮层（DMFC），产生两个 通往皮质下区域的主要通路;后部系统是 也包括两条主要的通路，一条从枕骨发出， 另一个来自顶叶皮层后系统达到 脑干眼动控制中枢通过上级丘; 前部系统与脑干有直接联系。主要 拟议工作的重点是了解这些 两个主要的皮质系统控制视觉引导的眼球运动， 特别强调目前相对较少的DMFC领域 是已知的。特别是知之甚少的是DMFC 控制着眼睛和肢体的运动， 可以被经验改变。拟议工作的目的是 确定（1）区域DMFC的各个区域如何控制眼睛、头部和肢体 运动，（2）DMFC的组织和额叶视野 在新的视觉运动任务的学习过程中改变，（3）如何改变 DMFC和前眼的药理学失活或病变 场影响视觉运动控制和（4）如何视觉引导眼睛- 运动控制受到影响时，成对的病变， 在包括前或后结构的隔离中 系统.为了回答这些问题，训练有素的恒河猴 将使用记录、刺激和损伤方法进行研究。一些 的工作将使用新开发的慢性多单- 细胞记录和微刺激。拟议的研究将 增加我们对眼睛和肢体运动的神经控制的知识 这对于理解人体运动功能障碍是必不可少的 由于脑损伤而失去控制。特别重要的是眼睛 肢体控制通常由几个系统并行执行 这使得通过系统留下的功能显著恢复 在脑损伤后完好无损

DESCRIPTION: Several neural systems contribute to the control of visually guided rapid eye movements which include portions of the occipital, parietal, and frontal lobes and the superior colliculi. The cortical regions involved can be divided into two major systems, the anterior and the posterior. The anterior system is comprised of the frontal eye fields and the dorsomedial frontal cortex (DMFC) that gives rise to two major pathways coursing to subcortical regions; the posterior system is also comprised of two major pathways, one emanating from the occipital and the other from the parietal cortex. The posterior system reaches brain-stem eye-movement control centers through the superior colliculus; the anterior system has direct connections to the brain-stem. The major focus of the proposed work is to understand the manner in which these two major cortical systems control visually guided eye movements, with special emphasis on area DMFC about which at present relatively little is known. Especially poorly understood is the manner in which DMFC controls both eye and limb movements and the extent to which its neurons can be altered by experience. The aim of the proposed work is to determine (1) how various regions of area DMFC control eye, head and limb movements, (2) how the organization of DMFC and the frontal eye fields is altered during the learning of new visuo-motor tasks, (3) how pharmacological inactivation or lesions of the DMFC and the frontal eye fields affects visuo-motor control and (4) how visually guided eye- movement control is affected when paired lesions are made that result in the isolation of structures that comprise the anterior or posterior systems. To answer these questions, trained, behaving rhesus monkeys will be studied using recording, stimulation and lesions methods. Some of the work will be done using newly developed chronic multiple single- cell recordings and microstimulation. The proposed research will increase our knowledge of the neural control of eye and limb movements which is essential for the understanding of malfunctions in human motor control due to brain damage. Particularly relevant is the fact that eye and limb control is often carried out in parallel by several systems which allows for significant recovery of function through systems left intact after brain damage.