NOREPINEPHRINE AND ATTENTIONAL MODULATION OF CORTEX

描述（申请人摘要）：顶叶皮层是一个视觉系统， 表示空间关系的区域。这种代表性具有 在人类和非人类中， 灵长类动物在后一种物种中，电生理测量具有 反复表明，“注意力”可以改变单细胞的反应， 在顶叶下小叶很少有研究调查了 生理机制是调节视觉反应的基础。 理解的缺陷不仅限于顶叶皮层， 对于其他皮质也存在类似的问题。目前的提案将是 第一个使用精确的神经药理学方法来解决 大脑皮层视觉反应的注意力调节问题 行为猴子这一办法将包括三个方面。行为上， 将电生理学和神经药理学方法相结合， 为了研究蓝斑弥散投射如何 改变皮层反应主要假设是去甲肾上腺素 释放是顶叶神经活动注意调节的基础 皮层具体地说，去甲肾上腺素的释放随蓝斑的不同而不同 活动改变个体的信噪比处理能力 锥体神经元和中间神经元的功能回路。测试 根据这个假设，猴子将被训练来完成一项行为任务， 其中难度和焦点的注意维度可能是 被系统地操纵。强度和空间分布 的神经表征将被定量评估为一个 注意力状态的功能，使用单单位记录方法。 微透析将用于测量细胞外去甲肾上腺素 程度.将进行药理学操作，以确认 去甲肾上腺素在这个部位释放然后去甲肾上腺素 将测量在不同注意力状态下的释放。相关性 将在电生理学和药理学之间绘制 措施恢复注意力缺陷的策略可能是 从这项工作中。

DESCRIPTION (Applicant's abstract): The parietal cortex is a visual region that represents spatial relationships. This representation has been shown dependent on attentional state in both human and non-human primates. In the latter species, electrophysiological measurements have repeatedly shown that "attention" can alter the response of single cells in the inferior parietal lobule. Few studies have examined what physiological mechanisms underlie the modulation of the visual response. The lacuna in understanding is not limited to the parietal cortex as similar issues exist for other cortices. The current proposal will be the first to use precise neuropharmacological methods to address the issue of attentional modulation of visual responses in the cortex of behaving monkeys. The approach will be three-fold. Behavioral, electrophysiological and neuropharmacological methods will be combined in order to examine how the locus coeruleus diffuse projections may alter cortical responses. The primary hypothesis is that norepinephrine release underlies attentional modulation of neural activity in parietal cortex. Specifically norepinephrine release varies with locus coeruleus activity altering signal-to-noise processing capabilities of individual pyramidal neurons and the functional circuitry of interneurons. To test this hypothesis, monkeys will be trained to perform a behavioral task in which the attentional dimensions of difficulty and focus may be systematically manipulated. The strength and the spatial distribution of the neural representation will be quantitatively evaluated as a function of attentional state using single unit recording methods. Microdialysis will then be used to measure extracellular norepinephrine levels. Pharmacological manipulations will be performed to confirm that norepinephrine is being released at this site. Then, norepinephrine release at different attentional states will be measured. Correlations will be drawn between the electrophysiological and pharmacological measures. Strategies for restoring attentional deficits may be derived from this work.