The influence of eye movements on visual cortical processing through the entrainm

描述(由申请者提供)：灵长类动物通过刻板的眼球运动主动采样视觉环境，主要包括被称为扫视的大跳跃。扫视通常每秒发生几次，并迅速将凝视位置重定向到视觉场景中的感兴趣区域。尽管眼动在视觉输入的选择和组织中具有基本的重要性，但它们在视觉处理中的功能作用仍然知之甚少。事实上，眼跳对初级视觉皮质(V1)神经元的活动有很强的影响，就像任何导致视觉输入突然变化的刺激一样。除了观察到V1神经元本身强烈地受到眼跳和类似眼跳的视觉输入的驱动外，最近的几项研究表明，眼跳也唤起了网络活动的刻板印象，包括持续的皮质网络振荡。这些网络振荡反映了皮质神经元兴奋性的节律性调制，并被认为在认知功能和视觉感知中发挥着重要作用。这表明，眼跳通过控制视觉输入和创造塑造信息处理的网络活动，在塑造神经元处理方面既有直接的作用，也有间接的作用。然而，要解开这些对神经活动的多重影响，需要实验条件既能再现眼球运动对网络的影响，又能在此背景下研究神经元刺激处理。因此，这项拟议的研究将研究眼跳如何调节大脑皮层网络活动，以及这种网络活动如何反过来调节刺激处理。这些问题将使用多电极阵列记录在清醒的灵长类动物中进行研究，使用定向刺激设计和新的功能建模方法。通过开发与眼球运动和模拟眼球运动相关的V1神经元如何对视觉输入做出反应的模型，可以直接测量眼跳的调制及其对视觉处理的影响。这项研究将首先研究眼跳和眼跳样刺激在大脑皮层网络振荡的夹带和同步中的作用。其次，这项研究将确定眼跳引发的网络活动如何调节单个神经元的刺激处理。这项工作将提供对皮层网络活动如何塑造感觉处理的关键见解，并将解决有关自然观看过程中眼睛运动在视觉处理中所扮演的角色的基本问题。对这些问题的理解对于将视觉感知与大脑皮层神经元和网络的活动联系起来非常重要。此外，了解眼跳如何构造神经活动和调节视觉处理将对神经假体的发展具有重要意义。

DESCRIPTION (provided by applicant): Primates actively sample the visual environment through stereotyped eye movements, primarily consisting of large jumps known as saccades. Saccades typically occur several times a second, and quickly redirect the gaze location to regions of interest in the visual scene. Despite the fundamental importance of eye movements in selecting and structuring the visual input, their functional role in visual processing remains poorly understood. Saccades in fact have a strong effect on the activity of neurons in the primary visual cortex (V1), as with any stimulus that results in sudden changes in the visual input. In addition to the observation that V1 neurons themselves are strongly driven by saccade and saccade-like visual input, several recent studies have shown that saccades also evoke stereotyped patterns of network activity, including the entrainment of ongoing cortical network oscillations. These network oscillations reflect rhythmic modulations of the excitability of corticl neurons, and are thought to play an important role in cognitive function and visual perception. This suggests that saccades have both direct and indirect roles in shaping neuronal processing, through both controlling the visual input and creating network activity that shapes this information processing. However, untangling these multiple effects on neural activity requires experimental conditions that can both reproduce the effects of eye movements on the network and allow the study of neuronal stimulus processing in this context. The proposed research will thus examine how saccades modulate cortical network activity, and how such network activity in turn modulates stimulus processing. These questions will be examined using multi-electrode array recordings in awake primates utilizing targeted stimulus design and novel functional modeling approaches. By developing models of how V1 neurons respond to visual input in relation to eye movements and simulated eye movements, the modulation by saccades and its effects on visual processing can be directly measured. The research will first examine the role of saccades, and saccade-like stimuli in the entrainment and synchronization of cortical network oscillations. Second, the research will determine how saccade- entrained network activity modulates the stimulus processing of individual neurons. This work will provide key insights into how cortical network activity shapes sensory processing, and will address fundamental questions about the role of eye movements in visual processing during natural viewing. An understanding of these issues will be important for linking visual perception to the activity of cortical neurons and networks. Furthermore, an understanding of how saccades structure neural activity and modulate visual processing will have important implications for the development of neural prosthetics.