NEUROBIOLOGY OF PREPARATORY SET IN MENTAL DISORDERS

这个项目的长期目标是了解大脑的准备 状态和过程，这些状态和过程使特定的环境事件是否 被感知或回应。 选择空间注意作为模型 这是一个探讨预备集的系统，因为它促进了 人类和动物的心理学和神经生理学 拟议 工作将有助于理解抑制的作用， 整合自愿和反射性视觉定向的机制， 提供视觉体验和视觉引导的连贯连续性， 人类的行为。 实验将检验扫视的效果 调节视觉的两种抑制现象的制剂 定向、返回抑制和注视偏移效应 (FOE)，他们将定义额丘回路在 调节扫视准备的效果。 他们将测量 预备训练对视觉反应的影响 信号在正常个体和患有慢性， 涉及背外侧前额叶皮层的单侧脑损伤， 后联合皮质和偏盲患者的纹状皮质 病变 这些实验将：1）确定皮质基底， 由外源视觉信号激活的基于位置和基于物体的返回抑制; 2)确定内源性生成的IOR是否影响基于位置的，或者 基于对象的表征; 3）定义额眼场的作用 在通过扫视准备的IOR的内源性产生中; 4）调查 扫视准备对朝向和远离扫视FOE的影响 从视觉目标信号; 5）定义额丘的作用 回路在调节扫视准备对FOE的影响。

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.