Neural Mechanisms of Human Visual Perception

人类视觉感知的神经机制

基本信息

批准号：
6795357
负责人：
FRANK TONG
金额：
$ 26.43万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-09-15 至 2006-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6795357
关键词：
behavior test behavioral /social science research tag binocular vision clinical research eye movements functional magnetic resonance imaging human subject neural information processing neurophysiology visual cortex visual fields visual perception

项目摘要

DESCRIPTION (provided by applicant): Human visual perception relies on both selective and constructive neural mechanisms to organize and to interpret visual information. The selectivity of perception can be seen in binocular rivalry, during which each eye views a different monocular pattern. Under these conditions, perception selectively alternates between one monocular image versus the other image every few seconds. Conversely, the constructive nature of perception may be best exemplified by perceptual filling-in of the blind spot in which vivid impressions occur in a visual location that lacks any input. Exactly how the brain mediates these complementary processes of perceptual selection and construction remains poorly understood. This project will use functional magnetic resonance imaging (fMRI) to investigate the neural basis of binocular rivalry and perceptual filling-in within human visual cortex. Our central hypothesis is that selective perception during rivalry and constructive perception during filling-in involve separate neural mechanisms that operate at different levels of the visual system. To investigate these issues, we have developed special behavioral and fMRI techniques to localize the cortical representation of the blind spot quickly and reliably, in previous studies, we have shown that fMRI activity in the monocular VI representation of the blind spot is tightly linked to perceptual awareness during rivalry, suggesting that rivalry results from early competition between monocular VI neurons. In contrast, when we stimulate the retinal region immediately surrounding the blind spot, we find evidence of a "hole" in visual activity in Vi but not in V2, perhaps suggesting that perceptual filling-in occurs in higher visual areas such as V2. The proposed research will characterize the neural mechanisms and visual areas responsible for rivalry and filling-in. More important, it will address scientific debates regarding whether: i) binocular rivalry arises from interocular competition versus pattern competition, and ii) perceptual filling-in arises from active neural completion versus passive remapping of visual inputs. This project will advance our knowledge of the neural organization of selective and constructive mechanisms in human visual perception. Such research is important given that vision serves as a primary sense for acquiring information from the environment to guide judgments and actions. The proposed studies will not only address the neural basis of human visual perception but will also inform research on visual dysfunctions and neurological disorders, including strabismus, amblyopia (suppressed vision in one eye), and the neural consequences of visual-field loss resulting from retinal or cortical injury.

描述（由申请人提供）：人类的视觉感知依赖于选择性和建设性的神经机制来组织和解释视觉信息。在双目竞争中可以看到感知的选择性，在此期间，每只眼睛都会观察到不同的单眼模式。在这些条件下，感知每隔几秒钟选择性地在一个单眼图像与另一个图像之间进行选择性交替。相反，感知的建设性可以通过盲点的感知填充来体现，在这种盲点中，在缺乏任何输入的视觉位置中会出现生动的印象。确切的大脑如何介导这些感知选择和构建的互补过程仍然知之甚少。该项目将使用功能磁共振成像（fMRI）来研究人类视觉皮层内双眼竞争和感知填充的神经基础。我们的中心假设是，在填充过程中对竞争和建设性感知期间的选择性感知涉及在视觉系统不同级别运行的单独的神经机制。为了调查这些问题，我们开发了特殊的行为和功能磁共振成像技术来快速，可靠地将盲点的皮质表示定位，在先前的研究中，我们表明，盲点单眼VI中的fMRI活性与竞争期间的竞争中的竞争性竞争中的竞争者之间的竞争性竞争与竞争性较早的VI Neurons之间的竞争结果紧密相关。相比之下，当我们刺激立即围绕盲点周围的视网膜区域时，我们发现VI视觉活动中的“孔”的证据，但在V2中没有发现，也许表明感知填充发生在较高的视觉区域，例如V2。拟议的研究将表征负责竞争和填写的神经机制和视觉区域。更重要的是，它将解决有关是否以下方面的科学辩论：i）双眼竞争是由眼内竞争与模式竞争引起的，ii）感知性填充是由主动神经完成与被动反映视觉输入引起的。该项目将促进我们对人类视觉感知中选择性和建设性机制神经组织的了解。鉴于视觉是从环境中获取信息以指导判断和行动的主要意义，因此这项研究很重要。拟议的研究不仅将解决人类视觉感知的神经基础，还将为视觉功能障碍和神经系统疾病的研究提供信息，包括斜视，弱视（一只眼睛抑制视力）以及视野性或皮质损伤引起的视觉场损失的神经后果。