Mechanisms of experience-induced brain plasticity in the adult speech system

成人言语系统中经验诱发的大脑可塑性机制

• 批准号: RGPIN-2020-06213
• 负责人: Tremblay, Pascale
• 金额: $ 4.01万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=760668
• 关键词: Mechanisms; experience; induced; brain; plasticity

Speaking is a remarkably complex human action whose neural architecture is still only partly understood. Despite tremendous progress in understanding the neural speech system, several questions remain regarding the organization of this system, its relationship to speech performance, and, importantly, its evolution over the adult lifespan. Despite a normal decline of structure and functions with age, the healthy adult brain retains a remarkable capacity to modify its structure and organization across the entire lifespan, following the acquisition of new skills, such as learning to speak a new language or to play a new instrument. This phenomenon is known as experience-dependent brain plasticity. In addition to skill learning, another method to induce brain plasticity is through the use of a device called "repetitive transcranial magnetic stimulation" or rTMS. rTMS delivers magnetic stimulation to specific brain areas and can modify their functioning, which can enhance behaviour. The objective of this research program is to better understand the neurobiology of the adult speech system by investigating how age and different kinds of experience can change the anatomy and functioning of the speech system. To achieve this general objective, a series of studies will be conducted. The first set of studies will focus on optimizing a rTMS protocol to enhance speech production by inducing plasticity in different regions of the speech system. Because brain stimulation technologies are not yet optimized for the study of speech, we will test different protocols for inducing plasticity in the speech system and identify the one that produces the most significant changes in younger and older adults. Using the knowledge generated in these studies, we will conduct a longitudinal speech training study consisting in learning to produce and perceive new speech sounds. Three groups of healthy adults will be recruited. One group will receive only the speech training. The second group will receive only rTMS. The third group will receive both. It is expected that the group receiving both rTMS and the speech training will show the most evidence of plasticity, behaviourally (enhanced speech performance) and in the brain, measured using magnetic resonance imaging (MRI). Behavioural and MRI measurements will be made at the beginning of the training, after 4 weeks and after 8 weeks, allowing us to examine the time course of behavioural and brain changes. This research program will advance current knowledge of experience-induced plasticity mechanisms in the healthy human brain. The proposed program will also contribute significantly to theories and knowledge about the neural speech system. Finally, the knowledge generated as part of the program will contribute to the development of brain-enhancing technologies and cognitive stimulation applications, which are being developed and patented across the world in the absence of adequate scientific and theoretical support.

说话是一种非常复杂的人类行为，其神经结构仍然只有部分被了解。尽管在理解神经语音系统方面取得了巨大进展，但关于该系统的组织、其与语音表现的关系，以及重要的是它在成人寿命中的演变，仍然存在一些问题。尽管结构和功能会随着年龄的增长而正常衰退，但健康的成年人大脑在获得新技能（例如学习说新语言或演奏新乐器）后，在整个生命周期中仍保留着改变其结构和组织的非凡能力。这种现象被称为经验依赖的大脑可塑性。除了技能学习之外，另一种诱导大脑可塑性的方法是使用一种名为“重复经颅磁刺激”或 rTMS 的设备。 rTMS 向特定大脑区域提供磁刺激，并可以改变其功能，从而增强行为。该研究计划的目的是通过研究年龄和不同类型的经历如何改变言语系统的解剖结构和功能，更好地了解成人言语系统的神经生物学。为了实现这一总体目标，将进行一系列研究。第一组研究将侧重于优化 rTMS 协议，通过诱导语音系统不同区域的可塑性来增强语音生成。由于大脑刺激技术尚未针对语音研究进行优化，因此我们将测试用于诱导语音系统可塑性的不同方案，并确定对年轻人和老年人产生最显着变化的方案。 利用这些研究中产生的知识，我们将进行纵向语音训练研究，包括学习产生和感知新的语音。将招募三组健康成年人。一组将仅接受言语训练。第二组将仅接受 rTMS。第三组将同时获得两者。通过磁共振成像 (MRI) 测量，预计同时接受 rTMS 和言语训练的小组将在行为（增强的言语表现）和大脑中显示出最多的可塑性证据。 行为和 MRI 测量将在训练开始时、4 周后和 8 周后进行，以便我们检查行为和大脑变化的时间过程。该研究计划将推进目前对健康人脑中经验诱发的可塑性机制的了解。所提出的程序还将对神经语音系统的理论和知识做出重大贡献。最后，作为该计划的一部分产生的知识将有助于大脑增强技术和认知刺激应用的开发，这些技术和认知刺激应用正在世界各地开发并获得专利，但缺乏足够的科学和理论支持。