 Hey friends, welcome back to another video. How much sleep did you get last night? Science recommends seven to eight hours for a full night's rest. It may be tempting to stay up for work, study or leisure and sacrifice some sleep, but science shows you could be sacrificing brain functions. Here are five things that happen to your brain if you don't get enough sleep. Number one, you'll be less alert. Are you paying full attention? If you didn't get enough sleep, you might not be as alert as you think. A study from South Australia gave participants a simple hand-eye coordination task to measure the effects of fatigue on alertness. After 10 hours awake, their average performance on the test took a downturn. After 24 hours awake, their alertness was just as impaired as people with a 0.10% blood alcohol level above the legal limit of intoxication in the United States. The study concluded that only one night without sleep is as mentally damaging as being too drunk to drive. Number two, your reaction times will be slower. How quickly do you react to what happens around you? Reacting quickly is important in many tasks, but research has also found concerning links between sleep loss and reaction times. Studies asked participants to press a button as quickly as possible after random cues. Even a small difference, like sleeping for six hours a night produced a significant slowing in reaction time. Some also failed to respond at all to some cues, which may be caused by microsleep periods where the brain temporarily lapses out of conscious awareness. Number three, your emotions will suffer. How's your mood after a night without sleep? Sleep-deprived individuals report extremely negative moods, high irritability, and volatile emotions. Research shows that sleep deprivation floods the body with stress hormones and causes you to blame others more and reduces the ability to solve problems and decrease self-esteem, empathy, and impulse control. Participants who were forced to stay up for 56 hours had clinically significant increases in depression, anxiety, and paranoia, showing that sleep is necessary for normal emotional functioning. Number four, your memory will decline. How many of the previous points do you remember? In sleep deprivation experiments, scientists have found that REM sleep, the deepest phase of sleep, is necessary to remember complex facts and procedures learned the previous day. When you have a big test coming up the next day, scientists recommend that you spend the night sleeping rather than cramming. Number five, your sense of humor will disappear. Do you think you're pretty funny? If you've been losing sleep lately, you may wanna think again. In a study by the Walter Reed Army Institute of Research, participants were deprived of sleep and shown some simple visual and verbal jokes. Their understanding of the jokes was far below average compared to healthy individuals. Even when given caffeine, their sense of humor was still highly stunted. Do you relate to any of the symptoms mentioned in this video? Let us know in the comments below. And don't forget to like and share this video if you think it might help someone else. The studies and references used are listed in the description below. Thanks so much for watching. Until next time, Psych2Goers.