Sleep can be disrupted by sleep paralysis.
Sleep . Although REM stands for `` rapid eye movement '' , this mode of sleep has many other aspects , including virtual paralysis of the body . Humans may suffer from various sleep disorders , including dyssomnias , such as insomnia , hypersomnia , narcolepsy , and sleep apnea ; parasomnias , such as sleepwalking and REM behavior disorder ; bruxism ; and circadian rhythm sleep disorders .