NEUROBIOLOGY OF PREPARATORY SET IN MENTAL DISORDERS

这个项目的长期目标是了解大脑的准备工作 偏向于某一特定环境事件是否将 被察觉或者回应。空间注意力被选为一个模型 一种探索预备集的系统，因为它促进了 人类和动物的心理学和神经生理学。建议数 这项工作将有助于理解抑制的作用 整合自主性和反射性视觉定向的机制 提供连贯的视觉体验和视觉指导 人类的行为。这些实验将检验扫视的效果。 调节视觉的两种抑制现象的制备 定向、返回抑制(IOR)与注视抵消效应 (FOE)，他们将定义额丘回路在 调节眼跳准备的效果。他们将测量 预刺激对视觉检测和反应的影响 正常人和慢性精神疾病患者的信号 单侧大脑损害累及背外侧前额叶皮质， 后联合皮质与纹状皮质偏盲患者 损伤。实验将：1)确定大脑皮质底物 由外源视觉信号激活的基于位置和基于对象的返回抑制； 2)确定内生IOR是否影响基于位置的IOR，或者 基于对象的表示；3)定义前部眼场的作用 在眼跳准备中内源性产生IOR；4)调查 眼跳准备对来回扫视对手的影响 从视觉目标信号和5)确定额丘的作用 调节扫视准备对敌人影响的回路。

The long-term goal of this project is to understand the brain preparatory states and processes which bias whether a given environmental event will be perceived or responded to. Spatial attention was selected as a model system for exploring preparatory set because it fosters a convergence of psychology and neurophysiology in both humans and animals. The proposed work will contribute to an understanding of the role of inhibitory mechanisms in integrating voluntary and reflexive visual orienting to provide a coherent continuity of visual experience and of visually guided behavior in humans. The experiments will examine the effects of saccade preparation on two inhibitory phenomena operative in regulating visual orienting, inhibition of return (IOR) and the fixation offset effect (FOE), and they will define the role of fronto-collicular circuits in mediating the effects of saccade preparation. They will measure the effect of preparatory precues on detecting and responding to visual signals in normal individuals and neurological patients with chronic, unilateral brain lesions involving the dorsolateral prefrontal cortex, the posterior association cortex and hemianopic patients with striate cortex lesions. The experiments will: 1) identify the cortical substrates for location-based and object-based IOR activated by exogenous visual signals; 2) determine whether endogenously generated IOR affects location-based, or object-based representations; 3) define the role of the frontal eye fields in the endogenous generation of IOR by saccade preparation; 4) investigate the effect of saccade preparation on the FOE for saccades toward and away from visual target signals and; 5) define the role of fronto-collicular circuits in mediating saccade preparation effects on the FOE.