REM [ back to Glossary Index ]
REM refers to rapid eye movement sleep. It was discovered in 1952 when pioneer sleep researchers observed the eyeballs of human infants jerking rapidly back and forth under their closed eyelids. They then observed the same thing in adult sleepers, and upon waking them, found that all of the sleepers had been in the process of dreaming and had excellent recall of their dream content. REM sleep is also known as paradoxical sleep because EEG frequency, the brain's rate of blood flow, glucose and oxygen consumption and acetylcholine secretion are all at waking levels, even though the person is truly asleep, immobile (due to complete lack of muscle tone) and out of touch with the external environment. REM makes up just 25% of the normal adult's normal 8 hours of sleep, but is very important because nearly all dreaming and all memory consolidation of newly learned facts and skills occurs during REM. TBI tends to cut back on the amount of REM sleep, and fragment what REM sleep remains, which means TBI reduces the amount of dreaming and memory consolidation activity in the brain.