An Expanded Visual Cortex for the Superior Colliculus

上丘视觉皮层的扩展

• 批准号: 10557091
• 负责人: Joshua Brenner
• 金额: $ 4.32万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10557091
• 关键词: 3-Dimensional; Anatomic Models; Anatomy; Animals; Architecture; Area; Automobile Driving; Brain region; Calcium; California; Cell Nucleus; Characteristics; Coupled; Darkness; Data Set; Detection; Discrimination; Ethology; Felis catus; Genetic; Goals; Head; Image; Inherited; Lateral Geniculate Body; Link; Mammals; Maps; Mentorship; Modeling; Motion; Movement; Mus; Neocortex; Neurobiology; Neurons; Output; Pathway interactions; Primates; Property; Pulvinar structure; Research; Retina; Role; San Francisco; Sensory; Signal Transduction; Stream; Structure; Synapses; System; Techniques; Testing; Thalamic structure; Universities; Viral; Vision; Visual; Visual Cortex; Visual Fields; Visual Motion; Visual Pathways; Visual System; Visual evoked cortical potential; Work; area striata; cell type; comparative; experimental study; extrastriate visual cortex; genetic approach; insight; neocortical; pharmacologic; response; retinotectal; superior colliculus Corpora quadrigemina; tool; visual information; visual motor; visual processing; visual stimulus

Project Abstract Studies of cortical visual processing in mammals have traditionally focused on the visual pathway that ascends from the retina to primary visual cortex (V1) via the lateral geniculate nucleus of the thalamus (LGN), the so-called geniculate pathway. However, visual information can also reach cortex through an alternate “extrageniculate” visual pathway in which retinal projections to the superior colliculus (SC) are relayed through the pulvinar nucleus of the thalamus (PN) before radiating to various regions of the visual cortex. While this extrageniculate pathway has been extensively characterized in primates and cats, its contribution to visually evoked activity in higher-order visual cortices is generally considered of lesser consequence than that of the geniculate pathway, at least in those higher-order visual cortices studied thus far. In the mouse, however, recent experiments from our lab have demonstrated that this extrageniculate pathway is actually the principal driver of visually evoked activity in a higher-order visual area called postrhinal cortex (POR). This discovery provides us with a well-defined system for studying the role of the extrageniculate pathway in cortical visual processing, a pathway that evolutionary neuroanatomists consider the ancestral visual input to the cortex. The mouse has about ten higher cortical visual areas whose visual response are thus far considered to largely rely on the geniculate pathway. The goal of this proposal is to use anatomical and functional approaches to determine the extent to which visual evoked responses in higher visual areas of the mouse rely on the extra-geniculate pathway. Elucidating these properties of the extrageniculate pathways to higher visual cortices of the mouse may ultimately provide a better understanding of their function in more classical mammalian models of vision, where the role of this evolutionary conserved pathway has remained somewhat elusive. Using transsynaptic viral tracing and widefield calcium imaging, I will assess the functional and anatomical characteristics of the mouse SC’s disynaptic projections to higher visual cortices via the pulvinar nucleus. I will take advantage of the unique response properties to moving visual stimuli of the SC to identify a putative set of SC-dependent higher visual cortices. Furthermore, I will compare those functional maps with the maps of the anatomical projections that disynaptically link the SC, via LP, to higher visual cortices. I will then use genetic and pharmacological tools to silence the SC and causally demonstrate the reliance of candidate cortices on this input. Finally, I will investigate a potential role of extrageniculate visual processing in discriminating between self and exogenously generated movement in the visual field. Taken together, this research will deepen our understanding of the relationship between the SC and visual cortex in the context of higher-order visual processing. The proposed experiments will provide a rich dataset from which to develop a successful doctoral dissertation under the close mentorship of world-leaders in cortical neurobiology at the University of California, San Francisco.

项目摘要 哺乳动物皮层视觉处理的研究传统上集中在视觉通路上 从视网膜通过丘脑外侧膝状核（LGN）上升到初级视觉皮层（V1）， 所谓的膝状体途径。然而，视觉信息也可以通过替代途径到达皮层。 “膝外”视觉通路，其中视网膜投射到上丘（SC）通过 丘脑枕核（PN），然后辐射到视觉皮层的各个区域。虽然这 膝外途径已在灵长类动物和猫中得到广泛表征，其对视觉的贡献 人们普遍认为，高阶视觉皮层诱发的活动的后果要小于视觉皮层的诱发活动。 膝状通路，至少在迄今为止研究的那些高阶视觉皮层中是这样。然而，最近在小鼠中 我们实验室的实验表明，这种外基因通路实际上是 称为后鼻皮质（POR）的高阶视觉区域的视觉诱发活动。这一发现为我们提供了 具有明确的系统来研究皮质视觉处理中的外齿通路的作用， 进化神经解剖学家认为祖先的视觉输入到皮层的途径。鼠标有 大约十个较高的皮层视觉区域，其视觉反应迄今为止被认为在很大程度上依赖于 膝状通路。该提案的目标是使用解剖学和功能性方法来确定 小鼠较高视觉区域的视觉诱发反应在多大程度上依赖于膝外 途径。阐明小鼠高级视觉皮层的基因外途径的这些特性 最终可能会更好地理解它们在更经典的哺乳动物视觉模型中的功能， 这种进化保守途径的作用仍然有些难以捉摸。 使用跨突触病毒追踪和宽场钙成像，我将评估功能和 小鼠 SC 通过枕丘向更高视觉皮层的突触突触投射的解剖学特征 核。我将利用 SC 对移动视觉刺激的独特响应特性来识别 假定的一组 SC 依赖的高级视觉皮层。此外，我会将这些功能图与 解剖学投影图，通过 LP 将 SC 与更高的视觉皮层进行非突触连接。然后我将使用 遗传和药理学工具使 SC 沉默并因果证明候选皮质的依赖性 在此输入上。最后，我将研究外基因视觉处理在区分中的潜在作用 视野中自身和外源产生的运动之间的关系。 总而言之，这项研究将加深我们对 SC 和 SC 之间关系的理解。 高阶视觉处理背景下的视觉皮层。所提出的实验将提供丰富的 数据集，在世界领导人的密切指导下撰写成功的博士论文 加州大学旧金山分校的皮质神经生物学。