NEURAL DYNAMICS AND THE PERCEPTION OF VISUAL FORM

神经动力学和视觉形式的感知

• 批准号: 2502429
• 负责人: TIMOTHY J GAWNE
• 金额: $ 9.61万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-12-01 至 2002-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2502429
• 关键词: Macaca mulatta; evoked potentials; form /pattern perception; neural information processing; neurons; saccades; stimulus interval; visual fields; visual perception; visual stimulus

When a primate views the world it makes a saccadic eye movement, and at the end of this movement the eyes remain more-or-less fixed in position for typically a third of a second, whereupon a new saccadic eye movement is performed. At the end of each saccadic eye movement the different pieces of the images of different objects are brought into the receptive fields of different assemblages of neurons. The visual scene is cluttered, with many objects overlapping and occluding each other. The activity elicited by the appearance of new stimuli in the receptive fields of neurons propagates through a loose hierarchy of cortical visual areas with a particular time course. The coordinated activity of many neurons in the different cortical areas during this interval between saccades is presumably what gives rise to visual perception. A great deal has been learned about the pattern of connections between the various cortical visual areas, and about the single aspects of a visual stimulus for which the individual neurons in each area are most sensitive to. However, less is known about how the visual system deals with complex stimuli, and for what (if many) role the time-varying aspects of neurons in the visual system might play. This study will address these issues by recording from single neurons and pairs of neurons in several cortical visual areas (V1, V2, V4, and IT) of awake behaving rhesus monkeys, using both simple and more complex visual stimuli, exploring the responses of neurons to stimuli that are either flashed on or brought into the receptive fields of neurons via a saccade, and quantifying the variation over time of neuronal responses under these conditions. The results of this project should now only increase our basic understanding of how the brain works, but should also be valuable for such efforts as the design of visual prostheses, where knowledge of the principles of neuronal encoding is vital, and also in the clinical interpretation of visually evoked potentials, which could be improved by a more detailed knowledge of the time course of visual processing.

当灵长类动物观察世界时，它会进行扫视运动， 在这个动作结束时，眼睛或多或少地保持在固定的位置上 通常持续三分之一秒，于是新的扫视眼球运动 进行。 在每次扫视眼球运动结束时， 不同物体的图像片段被带入接受者的大脑， 不同的神经元集合。 视觉场景是 杂乱，许多物体相互重叠和遮挡。 的 由接受神经元中新刺激的出现引起的活动 神经元通过皮层的松散层次传播 具有特定时间进程的视觉区域。 协调活动 在这段时间里，不同皮层区域的许多神经元 可能是产生视觉感知的原因 人们已经了解了很多关于 不同的皮质视觉区域，以及 视觉刺激，每个区域中的单个神经元最 敏感。 然而，关于视觉系统如何处理 复杂的刺激，以及什么（如果很多）作用的时间变化 视觉系统中神经元的某些方面可能起作用。 本研究将 通过记录单个神经元和成对的 清醒时几个皮层视区（V1，V2，V4和IT）的神经元 行为恒河猴，使用简单和更复杂的视觉 刺激，探索神经元对刺激的反应， 在神经元的感受野上闪现或通过一个 扫视，并量化神经元反应随时间的变化 在这种情况下。 该项目的结果现在只应 增加我们对大脑如何工作的基本理解，但也应该 对于视觉假体的设计等工作是有价值的， 了解神经元编码的原理是至关重要的， 视觉诱发电位的临床解释， 通过更详细地了解视觉的时间过程， 处理.