CONTROL OF VERGENCE EYE MOVEMENTS BY THE FRONTAL CORTEX

额叶皮层对眼球运动的控制

• 批准号: 6476324
• 负责人: James R Dearworth
• 金额: $ 4.42万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-12-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6476324
• 关键词: Macaca mulatta; binocular vision; eye coordination disorder; eye movements; frontal lobe /cortex; neural information processing; neurons; orientation; space perception; visual perception

Alert, rhesus monkeys will be trained to perform oculomotor tasks to clarify how neurons within the prearcuate cortex (8Ar) encode the visual characteristics of binocular stimuli that elicit vergence eye movements. Visually-guided vergence eye movements are reported to be composed of an initial transient vergence component and a later, sustained fusional component that "locks" vergence angle sufficiently for sensory fusion to occur. These components have been studied extensively in humans but not in the rhesus monkey. Initially, these components of vergence eye movements will be characterized in monkeys using the electromagnetic search coil method. Subsequently, these vergence components and the sensory stimuli eliciting them will be correlated with single-unit activity recorded from neurons within the prearcuate cortex. I. The first aim will characterize the behavior of neurons within the prearcuate cortex during the transient and sustained components of vergence. Briefly presented dichoptic images or long presentations of dissimilar images will separate transient vergence from sustained vergence. II. The second aim will look more closely at those visual characteristics encoded by neurons within the prearcuate cortex. A forced-choice paradigm will be used to determine what target characteristics (e.g. luminance, orientation, spatial frequency) affect transient vergence and neural activity. III. The final aim uses dichoptic stimuli that dissociate binocular matches based on local and global cues during transient vergence. Correlated, dynamic random-dot stereograms will test how prearcuate neurons respond to these global disparity cues. The results of this project will improve our understanding of neurological deficits associated with strabismus and of vergence dysfunction.

警觉，将训练恒河猴执行眼球运动任务，以阐明弧前皮质(8AR)内的神经元如何编码引发集中眼球运动的双眼刺激的视觉特征。据报道，视觉引导的会聚眼球运动由最初的瞬时会聚成分和后来的持续融合成分组成，该融合成分充分地锁定了会聚角度，使感觉融合发生。这些成分在人类中得到了广泛的研究，但在恒河猴身上还没有。最初，将使用电磁搜索线圈方法在猴子身上表征这些收敛眼球运动的成分。随后，这些融合成分和引发它们的感觉刺激将与从弓状前皮质内神经元记录的单个单位活动相关联。第一个目标将描述在聚焦的瞬间和持续成分期间弓状前皮质内神经元的行为。短暂呈现的分词图像或不同图像的长呈现将把瞬时收敛与持续收敛分开。第二个目标将更仔细地研究那些由弓状前皮质神经元编码的视觉特征。强制选择范式将被用来确定什么目标特征(例如，亮度、方向、空间频率)影响瞬时收敛和神经活动。最终目标是使用双眼刺激，在瞬间聚光过程中基于局部和全局线索分离双眼匹配。相关的动态随机点立体图将测试弓状前神经元对这些全局视差线索的反应。这个项目的结果将提高我们对与斜视和屈光功能障碍相关的神经缺陷的理解。