sleep deprivation

Sleep deprivation, also known as insufficient sleep or sleeplessness, is the condition of not having enough sleep. It can be either chronic or acute and may vary widely in severity.

A chronic sleep-restricted state adversely affects the brain and cognitive function. However, in a subset of cases, sleep deprivation can, paradoxically, lead to increased energy and alertness and enhanced mood; although its long-term consequences have never been evaluated, it has even been used as a treatment for depression.Few ...