Neural mechanisms underlying the computation of depth from motion parallax

视觉是一个积极的过程，我们经常移动我们的眼睛，以跟踪感兴趣的目标，因为我们 我们自己移动。虽然对保持目标上的中央凹很有用，但这些“追求”的眼球运动增加了 视网膜图像的全局运动模式。因此，为了计算物体在空间中的运动或深度， 在这个世界上，我们的视觉系统必须考虑到眼睛旋转所增加的图像运动。标准视图 除了视网膜成像运动之外的信号，例如追踪命令信号的输出拷贝， 必须用来补偿眼睛旋转。在这种观点中，人们会减去视觉运动 由眼睛旋转引起，使得其余部分传达有关眼睛中物体运动的信息 世界目前的项目评估了另一种观点，即视觉系统使用这种内部眼睛 运动信号作为关于相对于注视点的自运动的信息的代理。更 具体而言，对于目标1，我们建议使用非侵入性脑刺激（TMS）来研究是否 由额眼场（FEF）产生的视网膜外信号对于深度感知是必要的 从运动视差。如果TMS对FEF处理的干扰对深度感知有害， 运动视差，这将指示FEF是内部追踪信号的源，因此 是感知运动的神经处理机制的一部分。或者，如果TMS中断 FEF不影响运动深度的感知，这表明视觉系统 而是依赖于较早的感觉中心凹运动信号，即激发或驱动视网膜运动的特定信号。 追踪启动信号，在从运动视差的深度的神经计算中。目标2建议使用 TMS评估两个额外的大脑区域在从运动视差计算深度中的作用： 视觉区中颞（MT）和小脑蚓部。这两个领域都受到了牵连 在物体运动的感知中，并且被独特地定位以整合运动相关的和 根据运动视差计算深度所需的视网膜外追踪信号。然而，他们在深度上的作用 然而，在视觉感知方面，特别是在从运动视差计算深度方面，仍然不清楚。若TMS 如果这两个区域中的任何一个都扰乱了深度判断，这将表明在处理视网膜外追踪过程中的作用。 FEF产生的信号。我们以前的工作在理解 从运动中计算深度的理论、心理物理和神经生理机制 视差拟议的项目通过直接评估FEF的作用， MT和Vermis在从运动视差计算深度中的应用。

Vision is an active process, and we frequently move our eyes to track targets of interest as we ourselves move. While useful for maintaining the fovea on a target, these 'pursuit' eye movements add global patterns of motion to the retinal image. Thus, to compute the motion or depth of objects in the world, our visual system must account for the image motion added by eye rotations. The standard view is that signals other than retinal image motion, such as efference copy of pursuit command signals, must be used to compensate for eye rotations. In this view, one would subtract off the visual motion resulting from eye rotation such that the remainder conveys information about motion of objects in the world. The present project assesses an alternative view, that the visual system uses this internal eye movement signal as a proxy for information about self-motion in relation to the point of fixation. More specifically, for Aim 1, we propose to use non-invasive brain stimulation (TMS) to investigate whether extra-retinal signals generated by the frontal eye fields (FEF) are necessary for the perception of depth from motion parallax. If TMS disruption of FEF processing is deleterious to the perception of depth from motion parallax, this would indicate that FEF is the source of the internal pursuit signal and is therefore part of the neural processing mechanism for the perception of motion. Alternatively, if TMS disruption of FEF does not affect the perception of depth from motion, this would suggest that the visual system instead relies on an earlier sensory foveal motion signal, the specific signal that elicits or drives the pursuit initiation signal, in the neural computation of depth from motion parallax. Aim 2 proposes to use TMS to assess the role of two additional brain areas in the computation of depth from motion parallax: visual area Middle Temporal (MT) and the Cerebellar Vermis. Both of these areas have been implicated in the perception of object motion, and are uniquely positioned to integrate the motion-related and extra-retinal pursuit signals needed to compute depth from motion parallax. However, their role in depth perception, and in particular in the computation of depth from motion parallax, remains unclear. If TMS of either area disrupts depth judgments, this would suggest a role in processing the extra-retinal pursuit signal generated by the FEF. Our previous work has made important advances in understanding the theoretical, psychophysical, and neurophysiological mechanisms of computing depth from motion parallax. The proposed project extends these investigations by directly assessing the role of the FEF, MT, and vermis in the computation of depth from motion parallax.