Please note that this section contains my personal notes from my readings on this topic.
It’s been known for many years that the effect of lost sleep accumulates over time.
When adult volunteers have their sleep shortened by a constant amount, impairments in their mood and performance can be measured during the day. If the sleep disruption is repeated night after night, the actual measured impairments do not remain constant. Instead, there is an escalating accumulation of sleepiness that produces in adults continuing increases in headaches, gastrointestinal complaints, forgetfulness, reduced concentration, fatigue, emotional ups and downs, difficulty in staying awake during the daytime, irritability, and difficulty awakening. Not only do the adults describe themselves as more sleepy and mentally exhausted, they also feel more stressed. The stress may be a direct consequence of partial sleep deprivation or it may result from the challenge of coping with increasing amounts of daytime sleepiness.