Excessive daytime sleepiness (100% of affected individuals)
Cataplexy – a sudden loss of voluntary muscle tone (70% of affected individuals)
Sleep paralysis and/or vivid hallucinations (10 to 20% of affected individuals)
Microsleep (sleep episodes that only last a few seconds)
Nighttime wakefulness
Atonia (loss of muscle strength)
Involuntary leg muscle contractions
Rapid entry into REM sleep