NEURAL CONTROL OF THE PUPIL

这项研究的长期目标是了解这些机制 灵长类动物的瞳孔神经控制的基础。特别是， 建议进行实验，以研究人体的解剖学和生理学。 瞳孔光反射(PLR)。当光线照进一只眼睛时，那里 是那只眼睛和另一只眼睛的瞳孔收缩。前者 这种反应被称为直接的瞳孔光反射，而后者 这种反应被称为两厢情愿的瞳孔光反射。此外, 当观察到近处的物体时，会聚和适应是伴随而来的 通过瞳孔收缩--瞳孔附近的反应。尽管已经很久了 关于瞳孔神经控制的研究历史，现代研究很少 在灵长类动物身上进行了研究。因此，人体的解剖学和生理学 这些临床上重要的反射在灵长类动物中并没有得到很好的理解。 对警觉的、训练有素的灵长类动物的这些反射的研究对两个人来说都很重要 理由。首先，他们将提供关于神经的急需的信息 中枢神经对眼睛内部肌肉结构的控制 系统。第二，上面描述的瞳孔反射是非常 对临床医生诊断任何大脑的性质和范围都很有用 对人类的伤害。为了完整地解释这些方面的缺陷 必须很好地了解反射及其潜在的解剖学和生理学 在灵长类动物中。 为了解决上述提出的问题，建议的实验将是 在训练成跟踪视觉目标的恒河猴身上完成。解剖学和 电生理学研究将调查顶盖前的来源 向Edinger-Westphal核(EW)的投射可能介导 PLR.这些顶盖前投射对EW的行为作用将是 由利多卡因失活特定的顶盖前核和 Pre-tecto-EW纤维。鹅膏油酸注射，应尽量减少 可能参与的纤维通道，将被用于研究 不可逆转的顶盖前病变的影响。调查…的行为 顶盖前神经元介导灵长类动物的PLR，单个单位的活动将 被识别为投射到EW的顶盖前神经元使用 逆行激活和碰撞测试。已识别的电子战的行为 此外，还将使用相同的技术对瞳孔运动细胞进行检查。这个 他们的开眼率和瞳孔直径之间的关系将是 学习。此外，还将确定大脑中的前庭运动神经元是否 视觉诱发电位对近视反应和近视反应均有调节作用，如果它们起调节作用 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.