Now it’s this latter muscle that’s involuntary, so the crows feet smile is considered the real spontaneous emotion and is known now as the Duchenne smile.

现在发现眼轮匝肌的动作是无意识做出的，因此，带鱼尾纹的微笑被看成是情感的自然流露，誉为杜乡式微笑（发自内心的微笑）。

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They were also strapped into a giant centrifuge, where they had to read signals and answer questions despite dizziness, muscle contortions and involuntary spurts of tears.

他们还要被固定在巨型离心机里，经历头昏眼花、肌肉扭曲和无意识的流眼泪的同时，接收信号并回答问题。

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Seizures can vary from the briefest lapses of attention or muscle jerks, to severe and prolonged convulsions (i.e. violent and involuntary contractions, or a series of contractions, of the muscles).

癫痫的发作可能存有不同情况，从简短的意识丧失或肌肉反射到严重并且长期性抽搐(即肌肉的强烈和不自主性收缩或者一系列收缩)不等。

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Lethal electric fences, however, use a continuous current that can make a person lock on to the wire as voltage causes involuntary muscle contractions, paralysis and death.

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In the Alabama case, a consumer took Reglan and developed tardive dyskinesia, which causes incurable and involuntary muscle movements, and accused Wyeth, which is now owned by Pfizer, of failing to warn of the risk of long-term use.

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People who regularly get writer's cramp may be suffering from dystonia, a definition applied to a wide variety of conditions in which people suffer involuntary and often painful sustained muscle spasms.

BBC: writing