NEURAL CONTROL OF THE PUPIL

本研究的长期目标是了解 这是灵长类动物瞳孔神经控制的基础。 特别是， 实验提出，将调查解剖和生理 瞳孔对光反射（PLR） 当光线照射在一只眼睛， 是瞳孔收缩在眼睛和对侧眼睛。 前 这种反应被称为直接瞳孔光反射，而后者 这种反应被称为一致性瞳孔光反射。 此外，本发明还提供了一种方法， 当观察近处物体时，伴随着会聚和调节， 瞳孔收缩-瞳孔近反应。 尽管长期以来 关于瞳孔神经控制的研究历史，很少有现代研究 在灵长类动物中进行了研究。 因此，解剖学和生理学 这些临床上重要的反射在灵长类动物中还没有被很好地理解。 在警觉的、受过训练的灵长类动物中研究这些反射对于两个方面很重要。 原因 首先，它们将提供关于神经系统的急需信息。 通过中枢神经对眼睛内部肌肉组织的控制 系统 第二，上述瞳孔反射是极其 这对于临床医生诊断任何大脑的性质和程度都是有用的 对人类的伤害。 为了完全解释这些缺陷， 必须充分了解反射、其基础解剖学和生理学 在灵长类动物中。 为了解决上述问题，拟议的实验将 实验对象是被训练追踪视觉目标的恒河猴。 解剖和 电生理学研究将探讨前顶盖的来源， 向Edinger-Westphal核（EW）的投射可能介导 PLR。 这些前顶盖投射对EW的行为作用将是 通过利多卡因灭活特定顶盖前核和顶盖前核来确定 保护层-EW纤维 鹅膏蕈氨酸注射，这应该减少 潜在的参与纤维的通道，将被用来研究 不可逆的顶盖前病变的影响。 调查…的行为 在灵长类中，顶盖前神经元介导PLR，单个单位活动将 从被鉴定为投射到EW的顶盖前神经元记录， 逆向激活和碰撞测试。 已识别电子战的行为 还将使用相同的技术检查瞳孔细胞。 的 它们的放电率和瞳孔直径之间的关系将是 研究了 此外，将确定是否瞳孔神经元在 EW介导PLR和瞳孔近反应，或者如果它们介导 只有PLR。

The long-term objectives of this study are to understand the mechanisms underlying the neural control of the pupil in primates. In particular, experiments are proposed that will investigate the anatomy and physiology of the pupillary light reflex (PLR). When light is shone in one eye, there is a pupilloconstriction in that eye, and in the fellow eye. The former response is known as the direct pupillary light reflex, while the latter response is known as the consensual pupillary light reflex. In addition, when a near object is viewed, convergence and accommodation are accompanied by a pupilloconstriction - the pupillary near response. Despite a long history of research on the neural control of the pupil, few modern studies have investigated it in primates. Thus, the anatomy and the physiology of these clinically important reflexes are not well understood in primates. Studies of these reflexes in alert, trained primates are important for two reasons. First, they will provide much needed information on the neural control of the internal musculature of the eye by the central nervous system. Second, the pupillary reflexes described above are extremely useful to a clinician in diagnosing the nature and extent of any brain damage in humans. In order to completely interpret deficits in these reflexes, their underlying anatomy and physiology must be well understood in primates. To address the questions raised above, the proposed experiments will be done in Rhesus monkeys trained to track a visual target. Anatomical and electrophysiological studies will investigate the sources of pretectal projections to the Edinger-Westphal nucleus (EW) that might mediate the PLR. The behavioral role of these pretectal projections to EW will be determined by lidocaine inactivation of specific pretectal nuclei and of the pretecto-EW fibers. Ibotenic acid injections, which should minimize potential involvement of fibers of passage, will be used to study the effects of irreversible pretectal lesions. To investigate the behavior of pretectal neurons mediating the PLR in primates, single-unit activity will be recorded from pretectal neurons identified as projecting to EW using antidromic activation and collision testing. The behavior of identified EW pupillomotor cells will also be examined using the same techniques. The relationship between their firing rate and pupillary diameter will be studied. In addition, it will be determined if the pupillomotor neurons in EW mediate both the PLR and the pupillary near response or if they mediate only the PLR.