Dysfunctional Motor Automaticity in Focal Hand Dystonia in Musicians

描述（由申请人提供）：肌张力障碍是一种神经运动障碍，其特征是持续或间歇性的肌肉收缩，导致不必要的不自主运动。这种障碍可能是局灶性的（影响身体的一个区域），也可能是全身性的；这两种疾病可能有不同的病因。局灶性手肌张力障碍（FHD）的特点是手指和手的不随意肌肉收缩。它在器乐音乐家中发病率越来越高，当它发生在专业人士身上时，通常是职业生涯的终结。患有FHD的音乐家表现出运动学习方面的缺陷，以及与自动运动控制相关的大脑结构激活不足。运动序列的学习和表现通常被认为是受认知或自动控制的；认知控制需要将注意力集中在运动上，而自动表现则允许执行功能的自由。在演奏乐器时，音乐家需要对手指的动作进行认知控制和自动控制，所以精妙的演奏很可能发生在这两种控制机制的界面上。本项目将探讨自动控制和认知控制在FHD中的作用。总的假设是，FHD是由于特定过度学习任务的认知和自动控制之间的神经回路受损造成的。此外，在非局灶性肌张力障碍中，该界面可能受到的影响较小。患有FHD的音乐家、没有肌张力障碍的年龄匹配的音乐家、有涉及手的非局灶性肌张力障碍的非音乐家和没有肌张力障碍的非音乐家将在戴上仪器手套记录详细的运动运动学的同时执行一系列连续的手指敲击任务。这些任务将探索认知控制和自动控制之间的变量差异：敲击速度、保留和对潜在序列模式的明确知识。这一结果将为音乐家失去运动控制的神经回路提供重要信息

DESCRIPTION (provided by applicant): Dystonia is a neurological movement disorder characterized by sustained or intermittent muscle contractions causing unwanted involuntary movements. The disorder may be focal (affecting one body region) or more generalized; it is likely that the two entities have different etiologies. Focal hand dystonia (FHD) is characterized by involuntary muscle contractions in the fingers and hand. It has increased incidence in instrumental musicians, and, when it occurs in the professional, is usually career ending. Musicians with FHD demonstrate deficiencies in motor learning and an under-activation of brain structures associated with automatic motor control. Motor sequence learning and performance is generally thought to be either under cognitive or automatic control; cognitive control requires attention directed to the motor movements while automatic performance allows freedom for executive function. When playing an instrument, musicians require both cognitive and automatic control over finger movements, so exquisite performance likely takes place at the interface of these two control mechanisms. This project will investigate the role of automatic and cognitive control in FHD. The overall hypothesis is that FHD results from impaired neural circuitry at the interface between cognitive and automatic control of a specific over-learned task. Furthermore, this interface is likely to be less affected in non-focal forms of dystonia. Musicians with FHD, age-matched musicians without dystonia, non-musicians with non-focal dystonia that involve the hand, and non-musicians without dystonia will perform a battery of sequential finger-tapping tasks while wearing an instrumented glove to record detailed movement kinematics. The tasks will probe the variables that differ between cognitive and automatic control: tapping speed, retention, and explicit knowledge of underlying sequence patterns. The results will provide important information about the neural circuitry responsible for loss of motor control in musicians with FHD. Of immediate practical importance, the results of this project will determine whether a cognitive strategy-based therapy may provide benefit for musicians with FHD. Future studies will involve application of these findings to protective learning strategies in the context of skil learning requiring high repetition.