ATTENTION AND VOLUNTARY ACTION IN PREFRONTAL CORTEX

这一建议关注的是大脑是如何构建其 视觉空间的表示以及该表示如何在 运动计划和控制。关于这一关系，有很多观点 在视觉空间意识和自愿行动之间。一种观点是， 我们所感知的单一觉知只不过是 总共有大量低级感觉-运动程序相互作用 与物质世界的联系。另一种观点认为，大脑明确地 构建一种“心理工作空间”或通用的 独立于任何特定效应器系统的空间，以及 它使用此表示法进行汽车规划。关注和工作 记忆是这个高级空间的重要组成部分 代表权。大脑的哪些部分可能参与形成 这样的陈述吗？前额叶46区是一个很有希望的候选区域 大脑皮层。先前的研究表明，46区神经元编码 与行为相关的视觉刺激的位置，并保持这些 在工作记忆任务期间的在线表征，包括记忆- 指导式扫视任务。目前的提案审查了这一关系 46区神经元活动与眼球跳动程序的关系 动作和视觉引导的手臂动作。三个实验将 回答以下问题：1)46区神经元是否有能力 提供启动扫视和瞄准目标所需的信号 选择？2)区域46中的空间表示是否稳定 在持续的运动活动面前保持健壮吗？3) 第46区的单个神经元支持不止一种类型的计划 动静吗？总的目标是确定46区是否 在特定动作的计划和执行中的特定角色 在提供空间的多用途表示方面发挥更一般的作用 它可以被几个效应器系统以及引导隐蔽使用 空间注意力的转移。 这项提案中涉及的问题对 缺乏维持能力的精神障碍患者 适当地控制他们的行为，也包括那些无法 启动或控制帕金森氏症引起的自愿活动， 中风、癫痫或其他形式的神经损伤。建议数 实验应该提供关于认知和认知的有用信息 前额叶皮质的运动功能。这将有助于理解 额叶疾病，如精神分裂症和额叶 癫痫。

This proposal is concerned with how the brain constructs its representation of visual space and how this representation is used in movement planning and control. There are many views on the relationship between visual-spatial awareness and voluntary action. One view is that what we perceive as a unitary awareness is nothing more than the sum total of a multitude of low-level sensory-motor programs interacting with the physical world. Another view is that the brain explicitly constructs a "mental workspace" or general purpose representation of space which is independent of any particular effector system, and that it uses this representation for motor planning. Attention and working memory are important components of this high-level spatial representation. What parts of the brain might be involving in forming such a representation? One promising candidate is area 46 of prefrontal cortex. Previous work has shown that area 46 neurons encode the locations of behaviorally relevant visual stimuli and hold these representations on-line during working memory tasks, including memory- guided saccade tasks. The current proposal examines the relationship between neuronal activity in area 46 and the programming of saccadic eye movements and visually-guided arm movements. Three experiments will address the following questions: 1) Are area 46 neurons capable of providing the signals needed for saccade initiation and target selection? 2) Is the representation of space in area 46 stable and robust in the face of ongoing motor activity? 3) Can the activity of individual neurons in area 46 support the planning of more than one type of movement? The overall goal is to determine whether area 46 plays specific role in the planning and execution of particular movements or a more general role in providing a multi-purpose representation of space that can be used by several effector systems as well as guiding covert shifts of spatial attention. The issues dealt with in this proposal are of practical importance to sufferers of psychiatric disorders who lack the ability to maintain appropriate control over their actions, and also those who are unable to initiate or control voluntary movements due to Parkinson's disease, stroke, epilepsy or other forms of neurological damage. The proposed experiments should provide useful information about the cognitive and motor function of prefrontal cortex. This will aid in the understanding of frontal lobe diseases such as schizophrenia and frontal lobe epilepsy.