MRM FOR MAPPING FUNCTIONAL ARCHITECTURE OF VISUAL CORTEX IN FERRETS

用于绘制雪貂视觉皮层功能结构的 MRM

• 批准号: 6282339
• 负责人: DAVID FITZPATRICK
• 金额: $ 1.33万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 1999-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6282339
• 关键词: Mammalia; biomedical resource; human tissue; model design /development; nuclear magnetic resonance spectroscopy

Optical studies of the surface of the optical cortex of primates (cat, monkey, ferret) have shown that the neurons are organized in correlated groups having a 'blobby' appearance. Groups have a correlated response to, for example, stimuli by bar-shaped objects of a given orientation. Other, overlapped groups have similar response to differently oriented bars. The size of a group is on the order of 500 microns. The optical techniques are sensitive to the oxyhemoglobin-hemoglobin shift that occurs due to increased metabolism when the neurons are stimulated. The optical techniques are limited to viewing depths in the brain of about 100 microns. The goal of this research is to study this structure at a variety of depths in the cerebral cortex beyond those reached by optical means. Gradient echo 3D MR microscopy offers a unique opportunity as the only method to perform this kind of study. What is proposed is a pilot study to obtain 3D images (@ 7T) in the optical cortex of a ferret with 100 micron isotropic resolution while the animal is visually stimulated with an already validated stimulation protocol to evaluate the potential of MR microscopy in this application. The purpose of the pilot project will be to develop an MRI protocol for adequate functional imaging. We will try 3D projection imaging as well as 3D spin warp approaches. In addition, it will be necessary to ensure that the ferret can be adequately supported in the 7T system and that the optical stimulation system will function in/near the magnet. Note that the investigators already routinely use gas (halothane) anesthesia on these animals over the course of a several hour experiment and have experience and publications in the area.

灵长类动物视皮层表面的光学研究 （猫、猴子、雪貂）已经表明神经元的组织方式是 具有“斑点”外观的相关群体。 团体有一个 例如，对条形物体刺激的相关反应 给定的方向。 其他重叠的群体也有类似的反应 到不同方向的酒吧。 组的大小约为 500微米。 光学技术对 由于新陈代谢增加而发生的氧合血红蛋白-血红蛋白转变 当神经元受到刺激时。 光学技术有限 大脑中的观察深度约为 100 微米。 此举的目标 研究的目的是在不同深度上研究这种结构 大脑皮层超出了光学手段所能到达的范围。 梯度回波 3D MR 显微镜作为唯一的方法提供了独特的机会 进行此类研究。 建议进行一项试点研究 使用 100 获得雪貂光学皮层的 3D 图像 (@ 7T) 当动物受到视觉刺激时，微米各向同性分辨率 使用已经验证的刺激方案来评估 MR 显微镜在此应用中的潜力。 目的 试点项目将是开发一个 MRI 协议，以充分利用 功能成像。 我们将尝试3D投影成像以及3D 自旋扭曲接近。 此外，还需要确保 雪貂可以在 7T 系统中得到充分的支撑，并且 光学刺激系统将在磁铁内/附近起作用。 笔记 研究人员已经常规使用气体（氟烷） 在几个小时内对这些动物进行麻醉 在该领域进行实验并拥有经验和出版物。