CENTRAL AND PERIPHERAL PROCESSES IN VISUAL ADAPTATION

在自然观察条件下，物体的颜色和亮度 依赖于来自双眼的神经信号。这项研究将检验 从每只眼睛发出的信号的特性，以及中央机制的特性 将这些信号结合在一起。 对象很少被孤立地查看；相反，每个对象都是 提供对象所处环境的完整视觉场景 感觉到了。众所周知，物体的颜色和亮度是 受到视野中其他物体光线的影响，但知之甚少 关于结合每只眼睛的信号编码的神经过程 关于上下文的信息。最近的结果表明，亮度的变化 以及由双目融合的背景场引起的颜色外观， 由一个呈现给左眼的光和相应的光组成的 呈现给右眼，不能用改编的术语来解释 (A)仅左眼背景和(B)右眼背景的影响 单单是背景。这意味着中枢机制影响正常 (双眼)用普通眼睛无法观察到的色觉 仅将光线直接照射到一只眼睛的实验程序。在这 研究中，两只眼睛都将受到刺激，以测试基本特性 调节颜色和亮度的神经信号和中枢机制 感知力。 上述研究的一个长期目标是提供敏感和可靠的 有助于眼科疾病诊断的心理物理技术。 在一项相关的研究中，将研究一大批弱视患者。 检测和量化弱视眼的亮度缺陷，并 确定亮度缺陷和众所周知的缺陷之间的关系 在空间和时间的视觉上。眼睛之间的亮度匹配将是 用来衡量弱视眼睛的功能亮度水平。 然后，将测量每只眼睛的空间和时间敏感度， 非弱视眼的亮度级别设置为与 光线照射到弱视患者眼睛上的亮度。这项研究将 确定功能亮度级别可以考虑的程度 弱视的空间和时间缺陷。

Under natural viewing conditions, the color and brightness of an object depend on neural signals from both eyes. This research will examine properties of the signals sent from each eye, and of the central mechanisms that combine these signals. Objects seldom are seen in isolation; instead each object is part of a complete visual scene that provides a context in which the object is perceived. It is well known that the color and brightness of an object are affected by light from other objects in view, but very little is known about neural processes that combine each eye's signals that encode information about context. Recent results show that changes in brightness and color appearance caused by a binocularly fused background field, composed of one light presented to the left eye and a corresponding light presented to the right eye, cannot be explained in terms of the adapting effects of (a) the left-eye background alone and (b) the right-eye background alone. This implies that central mechanisms affect normal (two-eyed) color vision in ways that cannot be observed using common experimental procedures that direct lights to only one eye. In this research, both eyes will be stimulated to test fundamental properties of neural signals and central mechanisms that mediate color and brightness perception. A long-term goal of the above research is to provide sensitive and reliable psychophysical techniques to aid in the diagnosis of eye disorders. In a related line of research, a large sample of amblyopes will be studied to detect and quantify brightness deficits in amblyopic eyes, and to determine the relation between brightness deficits and well known deficits in spatial and temporal vision. Interocular brightness matching will be used as a measure of functional luminance level in the amblyopic eye. Then, spatial and temporal sensitivity will be measured in each eye, with the luminance level in the nonamblyopic eye set at a level that matches in brightness the light presented to the amblyopic eye. This research will determine the extent to which functional luminance level can account for spatial and temporal deficits in amblyopia.