Descriptive Psychopathology: The Signs and Symptoms of ...

171 Chapter 7: Disturbances of motor functionMovements associated with the parasomniaParasomnias occur during sleep, but are not due to the process responsible forsleep and wakefulness. They are most common in children, and involve theautonomic and motor systems.Arousal disorders expressed as “confusional” states, sleep walking or somnambulism,and night terrors have no characteristic motor features. Sleep–waketransition disorders occur at the transition between wakefulness and sleep, andbetween sleep and wakefulness, or between different stages of sleep.Rhythmic movement disorder (periodic limb movements) is characterized bystereotyped, repetitive movements, typically involving large muscle groups likethe head and neck, and occur from just prior to sleep onset into light sleep. Theylast minutes to hours, and consist of head banging, rolling, side-to-side movements,body rolling, leg banging, leg rolling, humming, or chanting. Patients areusually unresponsive during the events. Severe movements can cause injury.Frequent episodes are associated with daytime sleepiness. Mild forms and mostepisodes in children are seen in non-ill persons, but severe movements and adultonset episodes are associated with Gilles de la Tourette’s syndrome, and otherneurologic disease. About 30% will also have restless leg syndrome.Sleep “starts” (hypnopompic and hypnogogic jerks) are short, non-periodic,intense whole body myoclonic jerks of the large axial muscles or one or two limbsassociated with the subjective feeling of falling. Vocalization may accompany thejerk. Sleep jerks occur in normal persons as they fall asleep or awaken, during rapideye movement sleep, and as hiccoughs. When severe and frequent, sleep myoclonuscan elicit insomnia. Although myoclonus as a result of disease can occur alone(essential myoclonus), it is more often associated with other neurologic features. 75Nocturnal leg cramps are involuntary strong and painful contractions of theposterior muscles of the lower leg and foot lasting for seconds to minutes thatinterrupt sleep and that can be relieved by stretching. It may be familial and ismost common in women and the elderly. It may have no clinical significance orbe associated with hypertension, renal and vascular disease, diabetes, electrolytedisturbances, thyroid disease, Parkinson’s disease, and cancers.Somnambulism – sleep walking – is seen most commonly in children. Itusually consists of brief, aimless wandering associated with purposeless repetitivebehavior. Any vocalizations are short and monosyllabic. The patient is not fullyalert, but injury is unusual. Sleep walking occurs in deep non-REM sleep and thustypically during the first third of the night.Night terrors also occur in deep sleep early in the night. It is co-morbid withsleep walking. Episodes are brief, usually occur only once nightly, and arecharacterized by intense, inconsolable fear with signs of heightened sympatheticarousal. Like episodes of sleep walking, the sufferer is amnestic for the event.