WASHINGTON — When William Dement began working as a medical researcher in the 1950s, the topic of sleep was considered a yawn, scientifically speaking — an area perhaps appropriate for Freudian psychoanalysis but not for vigorous investigation by white-coated lab experts.
But with a pair of colleagues at the University of Chicago, Dr. Dement conducted some of the earliest studies of rapid-eye movement sleep, known as REM, which he identified as the stage in which most dreams happen. He also revealed the phases of the sleep cycle, using electroencephalograms to monitor subjects’ brain waves and polysomnography to track eye movements, blood oxygen levels, and other body functions during sleep.
Dr. Dement demonstrated that slumber was far from a single, passive state. And over the next few decades he helped turn the study of sleep into a robust scientific discipline, presiding over experiments on himself, his family, a few Rockettes dancers, a colony of narcoleptic dogs, and a teenager named Randy Gardner, who in 1964 claimed to have become the world’s champion insomniac by going 11 days without sleep.
His research and advocacy helped awaken the medical establishment to the dangers of sleep deprivation, which Dr. Dement and his colleagues linked to fatal car crashes and ailments such as diabetes. He also spotlighted the cardiovascular risks of disorders such as sleep apnea, in which a sleeper’s breathing is repeatedly interrupted.
‘‘He was the father of sleep medicine. Everything started with Bill,’’ said his Stanford colleague Emmanuel Mignot, an authority on narcolepsy. For years, Mignot added in a phone interview, Dr. Dement ‘‘was a voice in the wilderness, trying to draw attention to sleep issues at a time when it wasn’t taken too seriously.’’
Dr. Dement was 91 when he died June 17 at a hospital in Stanford, Calif. The cause was complications from a heart procedure, said his son, Nick Dement.
A passionate and even whimsical teacher and mentor, Dr. Dement was known for practicing what he preached, granting extra credit to students who nodded off in his undergraduate sleep class — then waking them up with a squirt gun and urging them to stand on their feet and declare, ‘‘Drowsiness is red alert!’’
The mantra served as a reminder that drowsiness could be deadly, especially on the road, and became a kind of motto for Dr. Dement. A onetime professional bassist, he was said to have turned from jazz to medicine after deciding that it was better to be a mediocre doctor than a mediocre musician. He went on to champion the creation of a jazz program at Stanford while notching a series of firsts in the field of sleep science.
Dr. Dement wrote one of the first university textbooks on sleep; founded the Stanford Sleep Disorders Clinic, considered the first of hundreds of sleep labs around the country; and created the first major professional organization for sleep researchers, now known as the American Academy of Sleep Medicine.
He was also a founding editor of Sleep, a prominent academic journal.
While treating sleep as a public health problem, Dr. Dement became a leading proponent of the importance of getting a good night’s sleep — generally six to eight hours, he said, with the length varying from person to person. ‘‘He really became an evangelist against drowsy driving,’’ said Rafael Pelayo, a longtime colleague. ‘‘Any time you hear someone talking about sleep and workplace safety, it’s all inspired by Bill Dement’s work.’’
He was also a scholar of narcolepsy and sleep apnea at a time when few scientists focused on sleep disorders. In the 1980s, he promoted research suggesting that as much as 20 percent of the population was suffering from sleep apnea.
Dr. Dement appeared on ‘‘The Tonight Show Starring Johnny Carson’’ and testified on sleep before Congress, helping to galvanize the creation of the National Commission on Sleep Disorders Research in 1988. With Dr. Dement as chairman, the commission issued a report finding that 40 million Americans suffered from chronic sleep disorders, with up to 30 million more experiencing intermittent sleep problems. Bleary-eyed employees, the commission estimated, resulted in $150 billion of reduced workplace productivity.
After the report was released in 1993, Congress created the National Center on Sleep Disorders Research, which coordinates research as part of the National Institutes of Health.
William Charles Dement was born in Wenatchee, Wash., on July 29, 1928, and grew up in Walla Walla, where his father’s family owned a flour mill. By the close of World War II he was serving in Japan with the Army, editing a regiment newspaper and developing a clear, concise writing style that later drew praise from academics.
In 1951 he received a bachelor’s degree from the University of Washington in Seattle.
Dr. Dement was training to become a psychiatrist when he became interested in sleep while at the University of Chicago, where physiologist Nathaniel Kleitman and graduate student Eugene Aserinsky were credited with discovering REM sleep in 1953. Building on their work, Dr. Dement later established the link between REM sleep and dreaming.
Dr. Dement received his medical degree in 1955 and his PhD in neurophysiology in 1957, both at the University of Chicago. While doing his medical internship at Mount Sinai Hospital in Manhattan, he set up a sleep lab out of his apartment, working with members of the Rockettes who apparently responded to an advertisement for a study. ‘‘He actually got the NIH to pay for half of his rent, because half of his apartment was to be used for sleep research,’’ Pelayo said.
His wife of 58 years, the former Eleanor ‘‘Pat’’ Weber, was ‘‘the glue’’ that kept the Stanford sleep community together, said Nick Dement. She died in 2014.
In addition to Nick Dement, a physician in Phoenix, Dr. Dement leaves two daughters, Elizabeth Dement and Catherine Roos, both of Stanford. His six grandchildren include Nick’s son Zaniel Zaiden Zooey Dement, whose initials — ZZZ — were selected in honor of Dr. Dement.