AMES, Iowa -- It may seem like a no-brainer that not getting enough sleep makes you angry, but a new Iowa State University study is one of the first to actually prove it with evidence.
According to ISU Professor of Psychology, Zlatan Krizan, other studies have shown a link between sleep and anger but questions remained about whether sleep loss was to blame or if anger was responsible for disrupted sleep.
The study found people with normal sleep actually had their frustration levels lower from one day to the next because they became accustom to the annoying noise used to measure anger. People who received a few hours less than normal not only were more angry, but actually became even more agitated with the noise the second day proving sleep deprivation impairs adaptation to frustrating circumstances.
"That's sort of to be expected. People tend to get used to frustrating conditions so the noise was not as unpleasant the second time and their level of anger and frustration tended to go down," Krizan said. "What was really interesting is individuals with sleep restriction conditions, they actually showed an opposite trend. Not just that it didn't get used to these frustrating conditions, they actually tended to report higher anger and higher distress."