An Expanded Visual Cortex for the Superior Colliculus

上丘视觉皮层的扩展

• 批准号: 10389616
• 负责人: Joshua Brenner
• 金额: $ 4.22万
• 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/10389616
• 关键词: 3-Dimensional; Anatomic Models; Anatomy; Animals; Architecture; Area; Automobile Driving; Brain region; Calcium; California; Cell Nucleus; Characteristics; Coupled; Data Set; Detection; Discrimination; Felis catus; Genetic; Goals; Head; Image; Inherited; Lateral Geniculate Body; Link; Mammals; Maps; Mentorship; Modeling; Motion; Movement; Mus; Neocortex; Neurobiology; Neurons; Output; Pathway interactions; Pharmacology; Primates; Property; Pulvinar structure; Research; Retina; Role; San Francisco; Sensory; Signal Transduction; Stream; Structure; System; Techniques; Testing; Thalamic structure; Universities; Viral; Vision; Visual; Visual Cortex; Visual Fields; Visual Motion; Visual Pathways; Visual evoked cortical potential; Visual system structure; Work; area striata; base; cell type; comparative; experimental study; extrastriate visual cortex; genetic approach; insight; 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， 从视网膜经由丘脑外侧膝状体核（LGN）上升到初级视觉皮层（V1）， 即所谓的膝状体通路。然而，视觉信息也可以通过另一种方式到达大脑皮层。 “膝状体外”视觉通路，其中视网膜投射到上级丘（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 膝状体外通路在灵长类动物和猫中已被广泛表征，其对视觉的贡献 高级视觉皮层的诱发活动通常被认为比 膝状体通路，至少在目前研究的高级视觉皮层中是这样。然而，在小鼠中， 我们实验室的实验已经证明，这种膝状体外通路实际上是 视觉诱发的活动在一个更高级的视觉区域称为后嗅皮层（POR）。这一发现为我们提供了 有了一个明确的系统来研究膝状体外通路在皮层视觉处理中的作用， 进化神经解剖学家认为，这是大脑皮层的祖先视觉输入途径。述小鼠具有 大约10个高级皮质视觉区域，其视觉反应迄今为止被认为在很大程度上依赖于 膝状体通路本提案的目标是使用解剖和功能方法来确定 在小鼠的较高视觉区域中的视觉诱发反应依赖于膝状体外神经的程度 通路阐明小鼠膝状体外通路的高级视觉皮层的这些特性 可能最终会提供更好的理解他们的功能，在更经典的哺乳动物模型的视觉， 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视野钙成像，我将评估功能和 小鼠SC经枕向高级视皮质双突触投射的解剖学特征 原子核我将利用SC对移动视觉刺激的独特反应特性来识别一个 推测的SC依赖的高级视觉皮层。此外，我将比较这些功能图与 解剖投影图，通过LP将SC与更高的视觉皮层进行双突触连接。然后我将使用 遗传和药理学工具，以沉默SC和因果证明候选皮质的依赖性 在这个输入。最后，我将研究膝状体外视觉加工在辨别中的潜在作用， 自我和外生运动之间的区别 总之，本研究将加深我们对供应链与 高级视觉处理中的视觉皮层。拟议的实验将提供丰富的 数据集，从中开发一个成功的博士论文下，世界领导人的密切指导下， 加州大学旧金山弗朗西斯科的皮质神经生物学。