Learning in the human motor cortex

描述(由申请人提供)：这项建议的长期目标是了解大脑如何学习和控制运动序列。正如拉什利在半个多世纪前认识到的那样，我们的大部分行为，从表演有组织的动作到使用语言的能力，都是基于我们检测、学习和产生序列的能力。在目前的方案中，我们使用人类受试者的系列反应时间(SRT)任务和功能成像的变体来检查负责学习运动序列的基本结构的神经底物，负责通过奖励和惩罚来调节学习的大脑区域，以及大脑在学习时间和空间序列时使用类似策略的程度。我们将检验以下假设。(1)在序列学习过程中，皮质运动区探测和学习从一个元素到下一个元素的转换，而基底节编码排序运动的整个结构。(2)奖惩对运动序列学习有直接但不同的影响，这将通过基底节活动的比例变化来反映。(3)时间间隔的学习序列将涉及与学习空间序列相似的一组大脑区域，而不涉及小脑。产生序列的能力受损是帕金森氏病患者残疾的一个重要组成部分。这里概述的工作将提供对这些残疾的基本了解，并可能导致制定这些患者的康复和治疗战略。

DESCRIPTION (provided by applicant): The long-term objective of this proposal is to understand how the brain learns and control movement sequences. As Lashley recognized more than half a century ago, much of our behavior, from the performance of organized movements to the ability to use language, is based on our capacity to detect, learn, and produce sequences. In the current proposal, we use variants of the serial reaction time (SRT) task and functional imaging in human subjects to examine the neural substrates responsible for learning the fundamental structure of movement sequences, the brain areas responsible for modulating learning through reward and punishment, and the extent to which the brain uses similar strategies for learning temporal and spatial sequences. We will test the following hypotheses. (1) During sequence learning cortical motor areas detect and learn transitions from one element to the next, while the basal ganglia encode the whole structure of sequenced movements. (2) Reward and punishment have direct but differential effects on motor sequence learning and this will be reflected by proportional changes in the activity of the basal ganglia. (3) Learning sequences of temporal intervals will engage a similar set of brain areas to those involved in learning spatial sequences and will not involve the cerebellum. Impairment in the ability to produce sequences is an important component of the disability experienced by patients with Parkinson's disease. The work outlined here will provide a fundamental understanding of these disabilities and may lead to the development of strategies for rehabilitation and treatment of these patients.