Mapping spatial working memory and attention in cortex

描述（由申请人提供）：顶叶、额叶和前额叶皮质脑损伤的患者通常在空间工作记忆和注意力过程中存在缺陷。这项研究的目的是阐明这些不同的大脑区域在空间位置的工作记忆中的功能，以及对这些位置的扫视或快速眼球运动的产生。具体目标有三：1。确定视觉引导和延迟扫视的视网膜病变是否存在于额叶皮质区。2.确定是否有地形图在较高的皮层区域记忆的目标角度听觉目标。3.确定当操纵杆朝向视觉和听觉线索移动时，记忆目标角度的较高皮层区域中是否存在地形图。将使用功能性磁共振成像测量大脑活动。受试者将通过投影图像的镜面反射获得视觉提示。听觉线索将通过耳机呈现，在时间、声级和频谱组成方面具有适当的耳间差异，以模拟源自三维空间的声音。经过一段时间的延迟后，受试者将向记忆中的刺激位置进行扫视或操纵杆运动。与刺激位置相关的脑活动将用于识别显示单峰或多峰感觉空间的地形图的那些更高皮层区域。这个项目是对空间位置记忆和注意力的神经生物学基础的调查。

DESCRIPTION (provided by applicant): Patients with brain damage to the parietal, frontal, and prefrontal cortex often have deficits in spatial working memory and attentional processes. The goal of this investigation is to clarify the function of these various brain regions in the working memory of spatial location and the generation of saccades, or rapid eye movements, toward those locations. There are three specific aims: 1. Determine if retinotopy of visually-guided and delayed saccades exists in frontal cortical areas. 2. Determine if there are topographic maps in higher cortical areas of remembered target angle for auditory targets. 3. Determine if there are topographic maps in higher cortical areas of remembered target angle when a joystick is moved toward visual and auditory cues. Brain activity will be measured using functional magnetic resonance imaging. Subjects will be presented with visual cues via a mirror reflection of a projected image. Auditory cues will be presented through headphones with proper interaural differences in timing, sound level, and spectral composition, in order to simulate sounds originating in three dimensional space. After a delay period, subjects will make a saccade or joystick movement toward the remembered location of the stimulus. Brain activity correlated with stimulus location will be used to identify those higher cortical regions that display topographic maps of unimodal or multimodal sensory space. This project is an investigation into the neurobiological basis for memory of and attention to spatial location.