这种多变性令很多人认为它的症状多样而不是单一明确的，这种多样化加大了对其病因的研究难度。

This variability has led many people to think of it as a spectrum of symptoms rather than a single, clear-cut syndrome. And that variability makes it hard to work out what causes it.

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尽管大多数情况下医生并不知道明确的病因，但是癫痫和脑损伤、肿瘤或者感染相关。

Although in many cases doctors don't know what causes it, epilepsy can be related to brain injury, tumors, or infections.

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现在，“青年隐蔽”的病因还不明确，但媒体通常报道说欺凌、考试不及格或者找不到工作之类的创伤性事件导致了这一问题。

And while it’s not clear exactly what causes hikikomori, traumatic events such as bullying, failing a test or not getting a job are often reported as triggers.

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