Sleep debt is the cumulative effect of not getting enough sleep. A large sleep debt may lead to mental and/or physical fatigue.

睡眠负债（sleep debt）指长期睡眠不足产生的影响。睡眠负债过多可能会导致精神或身体疲惫。

There are presumed to be two kinds of sleep debt, caused by partial sleep deprivation or total sleep deprivation. Partial sleep deprivation occurs when a person sleeps too little for many days or weeks. Total sleep deprivation means being kept awake for days or weeks.

睡眠负债的来源有两种：部分睡眠不足和整体睡眠不足。前者指一个人连续几天或几周每天都睡很短的时间；后者则指一个人连续几天或几周不合眼。

A long-term sleep debt may cause emotional upset, compromise work performance, weaken memory, alertness, attention as well as judgment. It may also speed up one’s ageing process and lead to other types of diseases.

长期处于睡眠负债的状况中，不但会影响情绪、工作表现、还会减低记忆力、警觉性、注意力和判断力、并且加速老化，甚至引发其它疾病。