Scattered  throughout the various reports on sleep research are several that describe some unusual behavior by people who are sleepwalking. These include eating, making phone calls and even murder. Now, there's a new case appearing in one more study on this strange phenomenon: sleep e-mailing. In an article published in journal Sleep Medicine, prefix = st1 /SetonHallUniversityresearchers document the following case of a 44-year-old woman: This woman received a puzzling phone call from a friend who said she was accepting her dinner invitation -- an invitation that the woman could not remember having made. The friend reminded the woman of the e-mail she had sent the night before -- an e-mail of which the woman also had no recollection . However, a quick search through her sent e-mail folder did turn up one strange e-mail. She had apparently sent it to her friend -- at 11:47 the previous night. The puzzling message said: "I don't get it. Please explain Lucy! Come tomorrow and sort this out! Dinner and drinks, 4 pm? Wine and caviar   to bring only. Everything else, a guess? There were two other e-mails sent to her friend at 11:50pm and 11:53 pm, each of which seemed to be written in a strange language, full of capitalization errors and phrases that didn't make sense. According to Dr Fouzia Siddiqui, lead author of the case study, this particular sleepwalking case was unique and was the first and only published account of "sleep e-mailing".  "Sleepwalking has occurred in the past where people would undertake other activities such as cooking or moving furniture around," Siddiqui said. " But this case is unique in that she wasn't just sleeping but doing complex things like turning on her computer, remembering her user name and password and typing entire e-mails." Just what is sleepwalking? It is actually a kind of sleep disorder. Studies have found that somewhere between 5 and 10 percent of people are sleepwalkers.  It comes from a mixture of wakefulness and non-REM   sleep. Sleepwalkers can carry out complex behavior such as driving, walking, e-mailing and telephoning in a sleep-like state. People with high levels of stress and anxiety, or those who have a family history of sleepwalking are more likely to experience it. What is the main idea of the passage?
It analyzes what sleepwalking is and its effects on people. It explains to readers why and how sleepwalking forms. It mainly reports on a recent unique case of sleepwalking. It tells about various kinds of sleepwalking there are.