This is a process called recruitment, or multiple motor unit summation. And it's where some of your muscles' more nuanced abilities come in.

这是一个叫做招募的过程，或多个运动单元求和。这就是你的一些肌肉更微妙能力的来源。

For a diagnosis of tourette's disorder, an individual must have multiple motor tics, and at least one vocal tic, however, these do not have to happen at the same time.

确诊Tourette综合征必须满足出现多种动作抽动以及至少一种发声抽动，不过这些抽动无须同时出现。

For a diagnosis of persistent motor or vocal tic disorder, also called chronic tic disorder, an individual must have either a single or multiple motor tics or vocal tics —but not both.

而要确诊慢性抽动障碍，即持续性动作或发声抽动，患者只需满足存在动作或发声性抽动的其中之一，不必两个兼具。