**6. Interdisciplinary relevance to medicine and law**

While studying the records of 20 patients admitted to intensive care units, who had a diagnosis of self-injurious sleep behavior disorders, between 1982 and 1990, at the Minnesota Regional Sleep Disorders Center, USA, Schenck and Mahowald [62] recognized that three among the 20 suffered from chronic night terrors/sleepwalking abnormality. The influence of various stressors commonly found in the intensive care units (such as sleeping in an unfamiliar setting, sleep disruption/deprivation, medication administration/withdrawal, and psychologic distress) may aggravate the condition of sleepwalkers is one inference from this study. From a retrospective chart review study of patients older than 15 years, admitted to the emergency department at a university hospital in Berne, Switzerland, Sauter et al. [71] inferred that life-threatening injuries associated with somnambulism may occur. As such, when patients present with falls of unknown origin, the possibility of somnambulistic cause should be considered. The 11 trauma patients, Sauter et al. [71] encountered, had injuries identified as contused facial lacerations, head injury, contusion of ribs, cervical spinal dislocation, and paraplegia below the thoracic vertebral body.

Self-caused injuries [71, 72] not-withstanding, to a confused public, somnambulism seems to be a puzzling phenomenon that flirts between the boundaries of medicine and the law. The pros and cons of the rights and penalties for this class of sleep disorder patients who commit serious crimes, including homicides [73], during somnambulistic episodes, continue to be debated without any resolution [74–84]. A controversial issue is the use of somnambulism defense in cases involving alcoholinduced homicides. In reviewing the scientific evidence and forensic considerations, Pressman et al. [85] had inferred that a defense of alcohol-induced sleepwalking or confusional arousal becomes a very attractive legal strategy with the potential of acquittal for the defendant. This, despite the fact "there is no direct experimental evidence that alcohol predisposes or triggers sleepwalking or related disorders."

Quite a number of reports have appeared in the last three decades, implicating somnambulism with sexual misconduct as well [86–88]. Among the nine cases of sleep-related violence and nine cases of sexual behavior in sleep, published between 1980 and 2012, the sleepwalking defense was proposed in 11 among these 18 cases [89]. In their review of these 18 cases, Ingravallo et al. [89] indicated that the trial outcome was in favor of the defendant in 14 of 18 cases. As the forensic evaluations widely differed from case to case, they had concluded that "an international multidisciplinary consensus for the forensic evaluation of sleep-related violence and sexual behavior in sleep need to be developed as an urgent priority." Though clinical descriptions of somnambulists with sexsomnia as anecdotal case reports show an increase in this century [32], probably due to its titillating factor in the digital mass media, it is not easy to replicate somnambulist-sexsomnia episodes in hospitalized setting, except on unusual conditions that such patients have a bed sharer of the same sex or opposite sex, during the observation period.
