Plasticity of the juvenile and adult rodent primary auditory cortex

幼年和成年啮齿动物初级听觉皮层的可塑性

• 批准号: 203175-2013
• 负责人: Dringenberg, Hans
• 金额: $ 2.91万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=523373
• 关键词: Plasticity; juvenile; adult; rodent; primary

Mammalian brains are highly plastic during early postnatal life, allowing the developing nervous system to adapt to the particular environment experienced after birth. The primary auditory cortex (A1), responsible for processing complex sounds such as communication signals, exhibits substantially more plasticity in juvenile animals than in adults. However, even adult brains (including A1) retain a significant plasticity potential, providing the neural basis for life-long learning. The present application addresses four fundamental objectives regarding plasticity of the developing and mature A1, using rats as a model organism. #1: Determine the precise role of sensory (sound) experience in guiding the maturation and stabilization of A1 synapses. #2: Characterize the postnatal development of different auditory perceptual skills (e.g., discrimination of loudness, pitch, or rhythmic patterns) and the influence of early sound experience on this developmental trajectory. #3: Assess synaptic mechanisms of auditory learning in the adult A1. #4: Determine the role of brain-generated estrogen (synthesized and released by A1 neurons) in A1 plasticity and auditory learning. These objectives are met by precise manipulations of the acoustic environment during development, behavioral techniques allowing animals to learn to distinguish various sounds, as well as electrophysiological and pharmacological techniques to assess levels of plasticity expressed by A1 neurons. This research program creates rich training opportunities for highly qualified personnel, allowing graduate and undergraduate students to acquire mastery of sophisticated scientific and professional skills, thus preparing them for advanced careers in academic or industrial/technological settings. Overall, the research outlined here will significantly advance our understanding of the development of auditory perceptual skills and auditory learning in adult animals, including brain mechanisms mediating these phenomena. Given the importance of auditory signals in animal (including humans) communication, this work can also provide insights into the evolution and development of sensory and brain systems mediating the sophisticated communicative abilities of many mammalian species.

哺乳动物的大脑在出生后的早期是高度可塑的，允许发育中的神经系统适应出生后经历的特定环境。初级听觉皮层（A1）负责处理复杂的声音，如通信信号，在幼年动物中表现出比成年动物更大的可塑性。然而，即使是成年人的大脑（包括A1）也保留了显着的可塑性潜力，为终身学习提供了神经基础。本申请使用大鼠作为模型生物体，解决了关于发育和成熟A1的可塑性的四个基本目标。#1：确定感觉（声音）经验在引导A1突触成熟和稳定中的确切作用。#2：描述不同听觉感知技能的出生后发展（例如，辨别响度、音高或节奏模式）以及早期声音经验对这一发展轨迹的影响。#3：评估成人A1听觉学习的突触机制。#4：确定大脑产生的雌激素（由A1神经元合成和释放）在A1可塑性和听觉学习中的作用。这些目标是通过在发育过程中对声学环境的精确操纵，使动物学会区分各种声音的行为技术，以及评估A1神经元表达的可塑性水平的电生理学和药理学技术来实现的。该研究计划为高素质人才创造了丰富的培训机会，使研究生和本科生能够掌握复杂的科学和专业技能，从而为他们在学术或工业/技术环境中的高级职业生涯做好准备。总的来说，这里概述的研究将大大推进我们对成年动物听觉感知技能和听觉学习发展的理解，包括介导这些现象的大脑机制。鉴于听觉信号在动物（包括人类）交流中的重要性，这项工作还可以为介导许多哺乳动物物种复杂交流能力的感觉和大脑系统的进化和发展提供见解。