The lab has investigated a variety of sleep disorders since it opened in September, but has only been fully funded since April 1. It has managed to operate on a "relatively low budget," explains Stakes, because the lab shares facilities with an electroencephalogram (EEG)--brain wave--laboratory which operates during the day.

Stakes estimates that 15 percent of the population suffer from sleep disorders of one kind or another. Some of the patients in the lab have been children as young as six, but as a rule, sleep deprivation does not begin the age of 11, when the child starts staying up late, usually to watch television.

Right now, his lab can accommodate only two patients, two nights a week, but Stakes says he plans to have it operating at capacity--three patients, two nights a week--within two or three years.

"The lab extends our diagnostic capability from just routine EEG sampling to a seven to eight-hour period of monitoring the patients," Stakes says.

McMahon says her favorite type of patient to monitor is the victim of "sleep terror," the "most interesting and scariest" disorder she's seen since she began to train as a technician at Mass General 13 years ago. Such a patient will awaken from non REM (rapid eye movement) of non dream sleep, in terror for no apparent reason.

Other disorders the lab deals with include nocturnal epilepsy (seizures only at night); nocturnal myoclonus (jerking of the legs during sleep) and narcolepsy.

Natcolepsy continual and unpredictable falling asleep during the day is a syndrome diagnosis according to Stakes. That is it can have many different causes, all with the same manifestation. Reasons for it include sleep deprivation, apnea metabolic diseases such as hypothyroidism tumors, and difficulty recovering from strokes.

Narcoleptics go into REM sleep the stage of sleep during which dreams occur much sooner than normal patients, and more often during the night. There is also another form of the disorder known as cataplexy, in which the victim loses muscle tone and control of the body when experiencing strong emotions, such as excitement or anger. Stakes tells of one patient who, when he tried to punish his children by whipping them was unable to do so because when he tried to remove his belt he became "very limp and weak."

Cataplectics generally remain conscious during attacks, but narcoleptics fall immediately into REM sleep. In either case, "some of these people have been labelled crazy, and they're not," says Stakes.

"If you can diagnose accurately, you can treat appropriately," he continues, explaining the "multiple sleep latency" test. During the course of one weekend a month, a patient is given the opportunity to sleep five times in 10 hours, and the sleep latency--time between going to bed and falling asleep--is measured.

Narcoleptics sleep at least two of the times, Stakes says, "within a couple of minutes," and enter REM sleep almost immediately. Normal sleepers take 15 to 20 minutes to fall asleep, and patients with disorders that involve not going into REM at all sleep within five minutes.

How does Stakes "treat appropriately?" Some disorders, such as insomnia, can be treated in the office. Other patients responded to antidepressant drugs, and some to simple adjustments in the sleep schedule. Still others only need reassurance that their sleep patterns are, in fact, normal. "We get patients coming in thinking they're not getting enough sleep when their sleep architecture looks great." Stakes remarks, referring to the structure of the printouts.

And he tells of an acquaintance who sleeps from 4 a.m. to 11 a.m. otherwise leading a normal life and conducting a successful law practice. The person has been on this schedule since college, when be arranged his schedule so he had all afternoon classes, as he did during law school.

But in the most severe cases, surgery is necessary. Apnea patients who do not respond to medication may need a pharyngoplasty, or surgical widening of the throat, and if the episodes are severe and frequent enough, a tracheotomy is called for.

This is the case with tonight's patient After the all-night session, the results of the monitors will confirm the diagnosis of a severe obstruction in his throat, and the need for a tracheotomy. In other words, the patient will have a permanent incision made in his throat, which will enable him to sleep uninterrupted by bypassing the block. "Laxity of the soft tissues in the throat and palate," according to Stakes, makes the operation necessary.