<unk> <unk><unk><unk>  disorder occurs when there is a loss of normal voluntary muscle atonia during REM<unk>  resulting in motor<unk>  in response to dream content. It can be caused by adverse reactions to certain drugs or during drug withdrawal; however, it is most often associated with the elderly and in those with neurodegenerative disorders such as Parkinson's disease and other neurodegenerative diseases, for example multiple system atrophy and the Lewy body dementias. The underlying cause of<unk>  is not well understood, but it is likely that<unk>  is an early symptom of synucleinopathy rather than a separate disorder. Brainstem circuits that control atonia during REM<unk>  may be damaged, including those in the pontomedullary brainstem. REM<unk>  circuits are located in caudal brainstem structures—the same structures that are known to lead to be implicated in the synucleinopathies. Motor deficits like those seen in<unk>  are known to result from lesions in those circuits. Risk factors for developing<unk>  are a family history of acting out dreams, prior head injury, farming, exposure to pesticides, low education level, depression, and use of antidepressants.<unk>  has also been reported following cerebrovascular accident and neurinoma (tumor), indicating that damage to the brain stem area may precipitate<unk> .<unk>  is usually chronic. However, it may be acute and sudden in onset if associated with drug treatment or withdrawal (particularly with alcohol withdrawal). Monoamine oxidase inhibitors, tricyclic antidepressants, Selective serotonin reuptake inhibitors, and noradrenergic antagonists can induce or aggravate<unk>  symptoms and should be avoided in individuals with<unk> .
Rapid eye movement sleep behavior disorder
Circadian rhythm sleep disorder
Delayed sleep phase disorder
Advanced sleep phase disorder
Shift work sleep disorder
Idiopathic hypersomnia
Nightmare disorder
Attention deficit hyperactivity disorder