Washington ? Night falls on the Coleman household in suburban Alexandria, Va., and it’s noisy. Startled cries come from a grandfather prone to World War II flashbacks; loud bouts of snoring bedevil the grandmother; shouts of “Quiet!” erupt from the bed-hugging, teenage grandson. The family didn’t exactly feel like springing forward a couple weeks ago.

“I hate daylight saving time,” said grandmother Ellen Coleman, a State Department employee who recently tested in an overnight sleep lab at Virginia Hospital Center. “I hate it for the morning after. … We have to turn the clocks ahead and we’re plunged back into darkness.”

Daylight saving time makes Coleman feel tired.

The same is true for most of her family and an estimated 40 million other Americans who have sleep disorders.

The nonprofit National Sleep Foundation, in its efforts to raise awareness of the hazards of bad sleep habits, recently released a poll reporting that Americans sleep almost two fewer hours a night than 40 years ago. The consequences of that can be dangerous: Studies show accidents rise in the days after the spring time change and drowsy drivers can be as impaired as drunken drivers.

Monthslong waiting lists for rooms in sleep labs attest to the demand for solutions to sleep-related misery.

As the problem of sleep deprivation has worsened, sleep research has advanced. Scientists have identified genes involved in sleep and have figured out which sections of the brain are responsible for behaviors such as suddenly falling asleep or knowing when to wake up.

Research under way

Scientists, medical industry leaders, military performance experts and inquisitive types are clamoring for more sleep research, and the National Institutes of Health in suburban Bethesda, Md., is responding. NIH spent more than $110 million on sleep-related initiatives and doubled the amount given in sleep research grants in the past decade, according to a 2003 NIH sleep task force report announcing a major expansion of the effort.

A trickle of sleep research is flowing from academia into examining rooms, giving millions a chance to function better.

“There’s been lots learned these last few years about the neurobiological basis of sleep,” said Eric Sklar, a neurologist with suburban Alexandria Fairfax Neurology and its SleepLab. “Now we’re able to tell people who come in complaining of fatigue, memory loss, ‘You’re not crazy, you’re not lazy, you don’t have a problem that no one knows anything about. You have an actual medical condition.’ And that alone means a lot.”

Neurological research in all fields got a boost from the unlocking of the human genetic code and the development of magnetic resonance imaging devices that allow scientists to peek inside the brain while subjects do activities such as reading or looking at photographs meant to evoke responses. The sleep deprivation resulting from many sleep disorders shows up as a darkening of the section of the brain responsible for complex thinking and organizational tasks.

Sleep researchers harnessed these new technologies and put them to work in experiments that led to insights into the function and biology of sleep.

In Boston, a neurological researcher at Brigham and Women’s Hospital discovered the location of sleep’s on-off switch and dubbed it the “circadian pacemaker.” In Palo Alto, Calif., a Stanford University research group identified the gene responsible for narcolepsy. Researchers found that sleep apnea, a potentially life-threatening condition in which airways clog, less oxygen gets into the blood and breathing often stops during sleep, is more common among obese people.

Disorder affects work

Shift-work sleep disorder, a disrupted sleep-wake cycle resulting from schedules that are at odds with the body’s internal clock, became a diagnosable condition, and a medication with the trade name Provigil won Food and Drug Administration approval to treat it. Clinical proof that sleep disorders affect job performance caught the interest of businesses, the government and the public. The Army and NASA are now studying ways to translate clinical data into keeping astronauts and soldiers awake.

Soldiers on battlefields or routine patrols are more dangerous to themselves than to the enemy when they haven’t slept enough, said retired Army Col. Gregory Belenky, who until recently was director of the neuropsychiatry division at Walter Reed Army Institute of Research.

Belenky debriefed soldiers involved in friendly-fire incidents in the Persian Gulf War and recorded symptoms characteristic of sleep deprivation. The sleep-deprived brain still sends signals for performing simple tasks, but it doesn’t do as well with more complex tasks.

Belenky and other Army researchers are developing a sleep-monitoring program that will involve a small number of soldiers in Iraq wearing devices that will record whether the subject is asleep, total sleep time and, eventually, biomedical data.

“It will allow commanders to see, soldier by soldier, small unit by small unit, how topped off people are not just on fuel and ammunition, but also on sleep, and then use this information to decide who should go on a particular mission and who should take a break,” Belenky said.