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.

哺乳动物的新皮质具有出色的变化能力，尤其是在早期 发展。皮质，感觉场及其连接的发展取决于 来自外围感觉受体的传入感官输入。这是早期的自发感官 输入，与环境的感官体验一起塑造新皮层以产生最佳 行为。我们从人类和啮齿动物的研究中知道，早期失去视力会导致大规模 大脑的变化；通常是视觉和后顶叶皮质区域的 仅对体感和听觉刺激反应的神经元。这种重组的枕皮层 接收来自丘脑核和与体感和皮质场的异位输入 听觉处理。当前的提案解决了这些提出的几个基本问​​题 以前的发现：1）盲目发作年龄如何差异影响皮层连通性 后顶叶皮层（PPCL和PPCM）的内侧和外侧分裂？ 2）什么是 PPCM和PPCL中的单神经元响应特性，并执行失明的年龄 这些属性？ 3）功能和解剖学变化PPCL和 PPCM和由不幸的感觉系统介导的补偿行为？在这些 实验，高度私人短尾负鼠（himodelphis himdera）中的双边涂料 将在两个发展里程碑上进行：1）在视网膜自发活动开始之前 在视网膜晶状体到达丘脑之前，在丘脑皮质轴突支配之前 新皮层； 2）当视网膜中的自发活动正在进行和视网膜生成时， 丘脑皮层轴突已经支配了目标。摘除后，将评估动物 两个时间点使我们能够直接评估重要发展的失明影响 里程碑。这些数据可以指导治疗干预措施，以弥补视力的丧失 目标高阶皮质功能。