الفهرس 
ParasomniasOnly 14 pages are availabe for public view
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Abstract
Parasomnias are defined by the ICSD-2 as undesirable physical events or experiences that occur during entry into sleep, within sleep, or during arousals from sleep. They are classified into disorders of arousal from NREM sleep, parasomnias usually associated with REM sleep, and other parasomnias.
Parasomnias are reported in approximately 4% of the adult population. Violent behavior during sleep has been reported in 2% of a large adolescent and adult population with a higher rate in the male sex. Many of parasomnias run in families, and genetic factors have been long suggested to be involved in their occurrence. The level and type of evidence for genetic effects varies much from parasomnia to parasomnia. The genetic factors are best established in enuresis, with several linkages to chromosomal loci, but their functions are not so far known. Environmental causes and gene-environment interactions are most probably of great importance in the origin of complex traits or disorders such as parasomnias.
The pathophysiology of parasomnias is based on overlap of the three states of being: NREM sleep, REM sleep, and wakefulness. Because the states are not completely discrete, wake can intrude into either sleep state resulting in purposeful or semi-purposeful activity. This manifests as disorders of arousal during NREM sleep; REM sleep behavior disorder, recurrent isolated sleep paralysis, or nightmare disorder during REM sleep; or other parasomnias. In addition, the projection of the loco-motor center to central pattern generators in the
Summary
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absence of higher cortical control may result in the complex motor behaviors seen in parasomnias.
Although these behaviors may appear purposeful or goal directed, the patient is not consciously aware of their actions. Therefore, parasomnia behaviors are not influenced by judgment and are potentially harmful.
In addition to the above, legal repercussions and parasomnia as a harbinger of neurodegenerative disease (in RBD) make the diagnosis of these disorders of vital importance. Signs that necessitate further evaluation of parasomnias are the presence of injurious or potentially injurious behavior, extreme disruption to other family members, presence of excessive daytime sleepiness, and association with medical, psychiatric, or neurological signs or symptoms.
Parasomnias and epileptic seizures can co-exist in the same subject making the differential diagnosis of these conditions particularly challenging. The difficulties in distinguishing nocturnal epileptic seizures from parasomnias reflect just one aspect of the intriguing issue of the pathophysiological relationships between all types of paroxysmal motor behaviors during sleep. In childhood, a frequent association between epilepsy and NREM arousal parasomnias or enuresis has been documented. As far as REM parasomnias are concerned, REM sleep behavior disorder, unrecognized or misdiagnosed, has been found to co-occur in 12% of elderly epilepsy patients.