Cross-modal plasticity after the loss of vision at two early developmental ages in the posterior parietal cortex: Adult connections, cortical function and behavior.

后顶叶皮质两个早期发育年龄视力丧失后的跨模式可塑性：成人连接、皮质功能和行为。

• 批准号: 10751658
• 负责人: Carlos Rodrigo Pineda
• 金额: $ 4.03万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10751658
• 关键词: Acoustic Stimulation; Address; Adult; Affect; Age; Age of Onset; Anatomy; Animals; Area; Auditory; Auditory area; Axon; Behavior; Behavioral; Bilateral; Blindness; Brain; Cannulas; Child; Compensation; Cortical Blindness; Data; Development; Electrophysiology (science); Environment; Environmental Risk Factor; Genetic; Goals; Human; Impairment; Implant; Inherited; Laboratories; Lateral; Mammals; Medial; Mediating; Microinjections; Modality; Monodelphis; Monodelphis Domestica; Movement; Muscimol; Neocortex; Neuroanatomy; Neurons; Occipital lobe; Parietal Lobe; Pathway interactions; Performance; Property; Research; Retina; Rodent; Sensory; Sensory Receptors; Shapes; Somatosensory Cortex; Tactile; Task Performances; Thalamic Nuclei; Thalamic structure; Therapeutic Intervention; Time; Tracer; Vibrissae; Vision; Visual; Visually Impaired Persons; Work; auditory processing; auditory stimulus; behavior prediction; behavior test; behavioral outcome; blind; experience; experimental study; fluorophore; grasp; kinematics; machine learning algorithm; mature animal; multimodality; neocortical; neural; receptive field; response; retinogeniculate; sensory input; sensory system; somatosensory; tactile stimulation; visual stimulus

The mammalian neocortex has a remarkable ability to change over a lifetime, particularly during early development. The development of the cortex, sensory fields and their connections are dependent on the incoming sensory inputs from the sensory receptors in the periphery. This early, spontaneous sensory input, together with sensory experience from the environment shapes the neocortex to generate optimal behavior. We know from studies in humans and rodents that early loss of vision leads to massive changes in the brain; what would normally be visual and posterior parietal cortical areas contains neurons that respond only to somatosensory and auditory stimulation. This reorganized occipital cortex receives ectopic input from thalamic nuclei and cortical fields associated with somatosensory and auditory processing. The current proposal addresses several fundamental questions raised by these previous findings: 1) How does the age of onset of blindness differentially impact cortical connectivity of the medial and lateral divisions of the posterior parietal cortex (PPCL and PPCM)? 2) What are the single-neuron response properties in PPCM and PPCL, and does the age of blindness onset impact these properties? 3) What is the relationship between functional and anatomical changes PPCL and PPCM and the compensatory behaviors mediated by the spared sensory systems? In these experiments, bilateral enucleations in the highly altricial short-tailed opossum (Monodelphis domestica) will be made at two developmental milestones: 1) Prior to the onset of spontaneous activity in the retina, before retinal geniculate axons reach the thalamus, and before thalamocortical axons have innervated the neocortex; 2) When spontaneous activity in the retina is ongoing and retinogeniculate and thalamocortical axons have innervated their targets. Following enucleations, animals will be assessed at two time points allowing us to directly assess the impacts of blindness at important developmental milestones. These data can direct therapeutic interventions to compensate for the loss of vision that targets higher-order cortical function.

哺乳动物的新皮质在一生中具有显着的变化能力，特别是在早期 发展。皮层、感觉场及其连接的发育取决于 来自周围感觉感受器的传入感觉输入。这种早期的、自发的感觉 输入以及来自环境的感官体验塑造新皮质以产生最佳的 行为。我们从对人类和啮齿动物的研究中得知，早期视力丧失会导致严重的视力丧失。 大脑的变化；通常视觉和后顶叶皮质区域包含什么 仅对体感和听觉刺激做出反应的神经元。这种重组的枕叶皮质 接收来自与体感相关的丘脑核和皮质区的异位输入 听觉处理。当前的提案解决了这些问题提出的几个基本问​​题 先前的研究结果：1）失明的发病年龄如何对大脑皮层连接产生不同的影响？ 后顶叶皮质的内侧和外侧部分（PPCL 和 PPCM）？ 2）有哪些 PPCM 和 PPCL 中的单神经元反应特性，以及失明发病年龄是否有影响 这些属性？ 3) 功能和解剖变化 PPCL 和 PPCM 和由幸免的感觉系统介导的补偿行为？在这些 实验，高度晚熟的短尾负鼠（Monodelphis Domestica）的双侧剜除 将在两个发育里程碑时进行：1）在视网膜自发活动开始之前， 在视网膜膝状体轴突到达丘脑之前，以及在丘脑皮质轴突受神经支配之前 新皮质； 2) 当视网膜的自发活动正在进行并且视网膜原化和 丘脑皮质轴突支配了它们的目标。摘除后，将在以下时间对动物进行评估： 两个时间点使我们能够直接评估失明对重要发育的影响 里程碑。这些数据可以指导治疗干预措施，以补偿视力丧失 目标是高阶皮质功能。