Sleep deprivation can also be caused by an underlying sleep disorder. You may wake up from sleep not feeling refreshed, and you may experience excessive sleepiness throughout the day. You may not even be aware that the cause of your daytime symptoms is sleep deprivation. Many people with sleep deprivation don’t know that they should feel differently than they normally do throughout the day, which is often what causes people to remain untreated for so long. Short-term effects of sleep deprivation include problems with memory and concentration, decreased performance, increased stress, reduced quality of life and an increase in both work and car-related accidents.