The Role of Areas V1 and V2 in Target Selection

描述(申请人提供)：这是一份修改后的申请，考虑到了评估最初提交的赠款的推荐人的意见。在另一个单独的部分，对批评做出了逐点的回应。初步研究部分已扩大到包括我们在过去六个月中进行的一系列试点实验，这些实验处理了裁判提出的中央批评，并提供了证据，证明拟议的项目是可行的，并可能导致对V1和V2区域在视觉引导眼球运动的目标选择中所起作用的重大新理解。这项拨款申请取代了我们决定不续期的EY00676《视觉系统中的并行信息处理》，因为该拨款项下的工作已经基本完成，而且我们所做的新发现要求我们的努力发生转变。 这项拟议的研究的目的是确定灵长类动物的V1和V2区域在选择眼球跳动的视觉目标时扮演什么角色。猕猴将接受各种行为任务的训练，以使我们能够研究它们的视觉能力，以及它们通过眼跳运动选择视觉目标的能力。单细胞记录、微刺激以及GABA能神经递质激动剂和拮抗剂的应用将用于评估V1和V2区如何相互作用，以及它们如何对视觉目标产生眼跳运动。这一建议是基于我们实验室最近的一组发现，该发现证实，这两个区域与目标选择和视觉引导的眼跳运动密切相关。这项工作表明，电刺激V1和V2颗粒下层在极低的电流水平下增强了对视觉目标的眼跳运动的产生，而刺激颗粒上层则干扰了目标的选择。除了阐明V1和V2在视觉引导的眼球跳动产生中的作用外，拟议的研究还应对视觉障碍者的微刺激假体产生重大影响，因为它将明确微刺激对视觉皮质不同层的影响，以及各种神经递质在这一过程中所起的作用。

DESCRIPTION (provided by applicant): This is a revised application that has taken into account the comments of the referees who have evaluated the initial submission of the grant. In a separate section, a point-by-point response is made to the criticisms. The Preliminary Studies section has been expanded to include a series of pilot experiments we had carried out the past six months that deal with the central criticisms advanced by the referees and provide evidence that the projects proposed are feasible and are likely to lead to significant new understanding of the role areas V1 and V2 play in target selection with visually guided eye movements. This grant application replaces EY00676 entitled Parallel information processing in the visual system that we decided not to renew because the work under that grant has been largely completed and because the new discoveries we had made dictate a shift in our effort. The aim of the proposed research is to determine what role areas V1 and V2 of the primate play in the selection of visual targets with saccadic eye movements. Rhesus monkeys will be trained on a variety of behavioral tasks to enable us to study their visual capacities and their ability to select visual targets with saccadic eye movements. Single-cell recordings, microstimulation, and the application of GABAergic neurotransmitter agonists and antagonists will be used to assess how areas V1 and V2 interact and how they contribute to the generation of saccadic eye movements to visual targets. The proposal is based on a recent set of findings from our laboratory that has established that these two areas are centrally involved in target selection with visually guided saccadic eye movements. The work has shown that electrical stimulation of the infragranular layers of V1 and V2 enhances the generation of saccadic eye movements to visual targets at very low current levels whereas stimulation of the supragranular layers interferes with target selection. In addition to clarifying the role of V1 and V2 in the generation of visually guided saccadic eye movements, the proposed research should have significant bearing on microstimulation prosthetics for the visually disadvantaged as it will specify the effects of microstimulation of different layers of the visual cortex and what roles various neurotransmitters play in the process.