HemiparesisHemiparesis, or unilateral paresis, is weakness of one entire side of the body (hemi- means "half"). Hemiplegia is, in its most severe form, complete paralysis of half of the body. Hemiparesis and hemiplegia can be caused by different medical conditions, including congenital causes, trauma, tumors, or stroke. Depending on the type of hemiparesis diagnosed, different bodily functions can be affected. Some effects are expected (e.g., partial paralysis of a limb on the affected side).
Sleep paralysisSleep paralysis is a state, during waking up or falling asleep, in which one is conscious but is unable to move or speak. During an episode, one may hallucinate (hear, feel, or see things that are not there), which often results in fear. Episodes generally last no more than a few minutes. It can recur multiple times or occur as a single episode. The condition may occur in those who are otherwise healthy or those with narcolepsy, or it may run in families as a result of specific genetic changes.
CataplexyCataplexy is a sudden and transient episode of muscle weakness accompanied by full conscious awareness, typically triggered by emotions such as laughing, crying, or terror. Cataplexy affects approximately 20% of people who have narcolepsy, and is caused by an autoimmune destruction of hypothalamic neurons that produce the neuropeptide hypocretin (also called orexin), which regulates arousal and has a role in stabilization of the transition between wake and sleep states. Cataplexy without narcolepsy is rare and the cause is unknown.
Post-polio syndromePost-polio syndrome (PPS, poliomyelitis sequelae) is a group of latent symptoms of poliomyelitis (polio), occurring at about a 25–40% rate (latest data greater than 80%). These symptoms are caused by the damaging effects of the viral infection on the nervous system. Symptoms typically occur 15 to 30 years after an initial acute paralytic attack. Symptoms include decreasing muscular function or acute weakness with pain and fatigue. The same symptoms may also occur years after a nonparalytic polio (NPP) infection.
Locked-in syndromeLocked-in syndrome (LIS), also known as pseudocoma, is a condition in which a patient is aware but cannot move or communicate verbally due to complete paralysis of nearly all voluntary muscles in the body except for vertical eye movements and blinking. The individual is conscious and sufficiently intact cognitively to be able to communicate with eye movements. Electroencephalography results are normal in locked-in syndrome. Total locked-in syndrome, or completely locked-in state (CLIS), is a version of locked-in syndrome wherein the eyes are paralyzed as well.
