Perceptual and Attentional Topography of Human Posterior Parietal Cortex

我们怎么记得东西在哪里呢？我们如何在忽略干扰的同时注意一些物体呢？大脑的一个部分支持这些和其他重要功能的处理，那就是后顶叶皮质。它涉及空间表征、注意力控制、眼睛和手的运动规划、数字感觉和工作记忆。尽管认知功能的重要性和多样性归因于大脑的这一区域，但它的功能组织还没有被很好地理解。以前对非人类灵长类动物的研究表明，这个区域由许多小的皮质区域组成，每个区域都有不同的功能。该项目的目标是：1)识别人类大脑皮层这一部分的不同功能亚区；2)揭示这些区域用于编码信息的空间表征；3)揭示这些亚区在视觉注意和视觉工作记忆中扮演的不同功能角色。在国家科学基金会的支持下，波士顿大学的大卫·萨默斯博士和他的同事们将通过功能磁共振成像来观察大脑的工作情况，从而解决这些问题。现在可以在单个受试者身上识别多达14个不同的大脑区域，每个区域都有一张完整的视觉空间地图。当人类志愿者试图注意和记住不同情况下的视觉刺激时，这些不同区域的活动将被测量。这项工作将揭示更全面的人类后顶叶皮质的功能组织以及支持视觉感知、视觉注意和视觉工作记忆的大脑机制。这项研究还可以识别大脑皮层的新的不同区域。这些研究对涉及后顶叶皮质的神经系统疾病和障碍的研究具有广泛的意义，包括阿尔茨海默病、威廉姆斯综合征和各种注意力障碍。这项研究还为本科生和研究生提供了认知神经科学和脑成像研究培训机会，包括那些来自代表性不足群体的学生。

How do we remember where things are? How do we pay attention to some objects while ignoring distractions? One part of the brain that supports the processing of these and other important functions is the posterior parietal cortex. It is involved in spatial representation, attentional control, planning of eye and hand movements, number sense, and working memory. Despite the importance and diversity of the cognitive functions attributed to this region of the brain, its functional organization is not well understood. Prior studies in non-human primates suggest that this area is comprised of many small cortical areas, each with different functional roles. The goals of this project are: 1) to identify distinct functional subregions of this portion of the human cerebral cortex; 2) reveal the spatial representations that these regions use encode information; 3) reveal the different functional roles that these subregions play in visual attention and visual working memory. With support from the National Science Foundation, Dr. David Somers and colleagues at Boston University will address these questions by seeing the brain at work with functional magnetic resonance imaging. As many as fourteen distinct brain regions, each with a complete map of visual space, can now be identified in individual subjects. Activity within each of these distinct areas will be measured while human volunteers attempt to pay attention to and remember visual stimuli in different situations.This work will reveal a more comprehensive picture of the functional organization of human posterior parietal cortex and of the brain mechanisms that support visual perception, visual attention, and visual working memory. This research also could identify new distinct regions of the cerebral cortex. These investigations have broad implications for the study of neurological diseases and disorders that involve posterior parietal cortex, including Alzheimer's Disease, Williams Syndrome, and a variety of attentional disorders. This research also offers cognitive neuroscience and brain imaging research training opportunities for both undergraduate and graduate students, including those from underrepresented groups.