NEURAL MECHANISMS FOR NATURAL VISION

我们的长期目标是了解复杂形式视觉的神经基础，因为它在自然观察条件下运作。几十年来，使用简单刺激和受控观察条件的视觉研究已经产生了早期视觉系统中复杂的处理模型。 我们建议直接评估这些模型记录下的条件下模拟自然视觉的反应。 在目标1中，我们建议使用自然主义和更标准的常规刺激来获取V1区的数据。 定量的方法将被用来估计细胞的时空滤波性能从这些数据。 实验和分析将揭示V1在自然视觉中是如何表征和处理信息的。 他们还将揭示这些功能与使用传统简单刺激的实验预测的功能有何不同。 在目标2中，我们将评估V1区的一系列功能计算模型，以确定那些可以解释模拟自然视觉过程中观察到的反应的模型。 这将通过模型之间的直接统计比较来完成。 这一目标的成功完成将导致第一个计算模型，可以解释V1神经元在自然视觉期间的时空响应。 在目标3中，我们将评估在模拟自然视觉过程中视网膜外因素（如注意力）的调节影响。 我们建议这样做，结合我们的自然刺激和我们的定量感受野估计方法的标准匹配到样本的行为任务。 这将为V1区的潜在视网膜外效应提供灵敏的测量。 对自然视觉的实验很重要，因为它们将使我们能够评估我们目前对人类视觉皮层功能的理论，并确定我们理解薄弱的区域。 它们还将使我们能够解决形状视觉的复杂方面，这些方面无法使用更传统的方法来处理。

Our long term goal is to understand the neural basis of complex form vision as it operates under natural viewing conditions. Decades of vision research using simple stimuli and controlled viewing conditions have produced sophisticated models of processing in the early visual system. We propose to evaluate these models directly by recording responses under conditions simulating natural vision. In Aim 1 we propose to acquire data in area V1 using both naturalistic and more standard conventional stimuli. Quantitative methods will be used to estimate cells' spatio-temporal filtering properties from these data. The experiments and analyses will reveal how are V1 represents and processes information during natural vision. They will also reveal how these functions differ from those predicted from experiments using conventional simple stimuli. In Aim 2, we will evaluate a range of functional computational models of area V1 to identify those models that can account for responses observed during simulated natural vision. This will be accomplished by direct statistical comparison between models. Successful completion of this Aim will result in the first computational model(s) that can account for the spatio-temporal responses of V1 neurons during natural vision. In Aim 3 we will assess the modulatory influence of extra-retinal factors such as attention during simulated natural vision. We propose to do this by combining standard match-to-sample behavioral tasks with our naturalistic stimuli and our quantitative receptive field estimation methods. This will provide a sensitive measure of potential extra-retinal effects in area V1. Experiments on natural vision are important because they will allow us to evaluate our current theories of human visual cortical function and identify areas in which our understanding is weak. They will also allow us to address complex aspects of form vision that cannot easily be approached using more conventional methods.