Behavioral and neural characteristics of adaptive speech motor control

项目总结/摘要 感觉运动学习在所有熟练动作的获得和改进中起着关键作用，包括 言语产生从早期的牙牙学语到完全成熟的言语清晰度， 中枢神经系统过程参与获取和更新复杂的神经表征 从运动指令到声道运动和语音输出的运动到听觉的转换。 听觉-运动学习也被认为在发展性言语的病因学中起着重要作用 口吃和儿童言语失用症等疾病。在过去的二十年里，PI的实验室 为该领域理解这种语言的关键机制做出了重要贡献 儿童和成人的运动学习。我们现在提出了一个新的系列实验，结合 行为学习范式与高度创新的神经生理学方法，使我们能够 调节并记录皮层下的神经活动具体来说，我们的目标是调查（一）如何语音听觉- 可以增强运动学习以及如何最小化学习的衰减，（B）前馈是否 认知运动学习还推动反馈控制策略的更新，（c）理论见解可以 从“追随者”的个体子集中获得，并且矛盾地使用导致 增加听觉错误，而不是适应，和（d）是否，在神经水平，小脑和基底 神经节回路在言语记忆-运动学习中与其他形式的言语运动相比起着独特的作用 学习纳入实验的神经基础的神经运动学习利用国家的最先进的 最新的脑深部电刺激（DBS）植入物中可用的传感技术，电极位于 丘脑腹侧中间核（接受小脑输出）或丘脑底核（基底神经节）。 总的来说，这些综合实验将阐明过程，机制和神经基板 参与言语记忆-运动学习。它们也会揭示听觉的发展过程- 运动学习，儿童和成人之间的认知运动学习的差异，以及相似性和 言语感觉运动学习与肢体感觉运动学习的差异。此外，考虑到听觉- 运动适应范例使说话者快速且不费力地隐含地改变他们的语音输出， 这项工作支持开发新型计算机辅助临床程序的未来长期目标 通过系统地改变说话者的听觉反馈来诱导言语行为的适应性变化。 因此，这项工作与公共卫生直接相关，因为产生的知识将加深我们的理解 典型的言语发展，在整个生命周期中保持言语清晰度技能， 发展性言语障碍的基本感觉运动机制，同时 为治疗各种语言障碍的高度创新的临床技术铺平了道路。

PROJECT SUMMARY/ABSTRACT Sensorimotor learning plays a critical role in the acquisition and refining of all skilled movements, including speech production. From early babbling to fully mature speech articulation, auditory-motor learning reflects central nervous system processes involved in acquiring and updating neural representations of the intricate motor-to-auditory transformations from motor commands to vocal tract movements and speech sound output. Auditory-motor learning is also believed to play an important role in the etiology of developmental speech disorders such as stuttering and childhood apraxia of speech. Over the past two decades, the PI’s laboratory has made important contributions to the field’s understanding of the key mechanisms underlying such speech auditory-motor learning in children and adults. We now propose a novel series of experiments, combining behavioral learning paradigms with a highly innovative neurophysiological approach that allows us to both modulate and record subcortical neural activity. Specifically, we aim to investigate (a) how speech auditory- motor learning can be enhanced and how decay of learning can be minimized, (b) whether feedforward auditory-motor learning also drives updates in feedback control policies, (c) which theoretical insights can be gained from the subset of individuals who are “followers” and paradoxically use a control strategy that leads to increasing auditory error rather than adaptation, and (d) whether, at the neural level, cerebellar and basal ganglia circuits play a distinct role in speech auditory-motor learning versus other forms of speech motor learning. The inclusion of experiments on the neural bases of auditory-motor learning leverages state-of-the-art sensing technology available in very recent Deep Brain Stimulation (DBS) implants with electrodes in either thalamic ventral intermediate nucleus (receiving cerebellar output) or subthalamic nucleus (basal ganglia). Overall, these integrated experiments will elucidate the processes, mechanisms, and neural substrates involved in speech auditory-motor learning. They will also reveal the developmental progression of auditory- motor learning, differences in auditory-motor learning between children and adults, as well as similarities and differences in speech sensorimotor learning vs. limb sensorimotor learning. Furthermore, given that auditory- motor adaptation paradigms cause speakers to implicitly alter their speech output quickly and without effort, this line of work supports the future long-term goal of developing novel, computer-assisted clinical procedures that induce adaptive changes in speech behavior by systematically altering the speaker’s auditory feedback. Thus, the work is directly relevant to public health as the generated knowledge will deepen our understanding of typical speech development, the maintenance of speech articulation skills throughout the lifespan, and fundamental sensorimotor mechanisms underlying developmental speech disorders while simultaneously paving the way for highly innovative clinical techniques for the treatment of a variety of speech disorders.