On the night, several years ago, that I tackled my nightstand, I should have known better. Jolted awake in the dark, my wife Alice peered over the covers to where I lay spread-eagled on the floor. I had lunged with open arms from our bed while still asleep, truly, I later mused, the consequence of an overactive imagination, all the more because my days playing football were long over. Alice joked that we should dust off the kids’ bed rails.
Since that night, we have been forced to take my wildest dreams more seriously. In a re-occurrence months later, I “blocked” Alice in bed, envisioning instead a defensive lineman (fortunately, despite her diminutive size, she was not hurt); and, more recently, I punched the headboard with my fist, thinking instead that I was protecting my parents from an assailant. What makes these incidents all the more bizarre is that three years ago, having written on the history of sleep, including its disorders, I began to collaborate with Dr. John Shneerson, the director of the largest sleep center in the United Kingdom, at Papworth Hospital. Our project: a series of papers devoted to sleep violence.
Despite the anguish caused by insomnia, it is far from the most frightening sleep abnormality. Nor, in contrast to the terror of nightmares, are the consequences of sleep violence confined to the unconscious. In extreme cases, sleepers have been known to inflict violence, even death, upon family members as well as physical injury or worse upon themselves. Some subjects, in doing so, never quit their beds, while others leave not only their beds but also their bedrooms, not unlike individuals prone to the related disorder of sleepwalking.
The term “sleep violence” encompasses several possible conditions, although some of these occasionally overlap with others. One of the most common disorders, especially among children, are night terrors, occasioned by momentary, frightening hallucinations, resulting in panic and confusion. Only in late adolescence and early adulthood, however, are subjects apt to commit violence, particularly if restrained. More sensational is R.E.M. Sleep Behavior Disorder (R.B.D.), which was formally identified in 1985 by sleep specialists at the University of Minnesota and Stanford. Insofar as we dream during the phase known as R.E.M. or rapid eye movement sleep, R.B.D., in contrast to other forms of sleep violence, is characterized by vivid dreams, distinguished by their narrative quality, which portray threatening persons or objects. Mild instances result in restlessness and abnormal twitching in bed; more serious are occasions when subjects, in acting out their dreams, attempt to fight back against their imaginary foe, thereby raising the risk of serious injury.
http://opinionator.blogs.nytimes.com/2010/03/23/violence-in-the-land-of-sleep/?th&emc=th