Allan Rechtschaffen, PhD, sleep research pioneer, 1927-2021

Dr. Rechtschaffen was a seminal figure in our understanding of the biological functions and purpose of sleep, including the various stages of sleep and the detrimental effects of sleep deprivation.

Allan Rechtschaffen, Professor Emeritus of Psychology, Psychiatry and the College, Director of the University of Chicago Sleep Laboratory for more than 40 years and a pioneer of modern sleep research, died at his home on November 29, 2021. He was 93 years old.

Al, as he was affectionately known by his family, many friends and colleagues, was a seminal figure in our understanding of the biological functions and purpose of sleep, including the various stages of sleep and the detrimental effects of sleep deprivation. He also played a key role in establishing sleep research as an academic and clinical medical discipline in the 1960s.

“Al had a single-mindedness about his work. His whole career was devoted to understanding the function of sleep,” said Thomas Roth, Director of the Sleep Disorders and Research Center at Henry Ford Hospital in Detroit. “He created the infrastructure and built the foundations that were necessary to create an environment where other people could expand the field into what it is today. If you ever needed to know anything about sleep, you just asked Al.”

Rechtschaffen came to the University of Chicago in 1957, where he joined the faculty with Nathaniel Kleitman, who had established the world’s first sleep laboratory and is universally recognized as the father of sleep research. In 1953, Kleitman and one of his students, Eugene Aserinsky, discovered rapid eye movements (REM) during sleep and first suggested that they were associated with dreaming. Rechtschaffen, taken by Kleitman’s work, began his own research on REM sleep and dreams, but his interests quickly led to the biological function and purpose of sleep, which preoccupied him for the next 44 years.

He was fixated on a fundamental question: “Why do we sleep?” All mammals, birds, and reptiles sleep in some form or another, whether it’s bundled up in a cozy bed, burrowed into a hole in the ground, or floating in the water. Sleep obviously serves an important biological purpose, but as Rechtschaffen once pointed out, it seems contrary to survival. “Sleep precludes hunting for and consuming food. It is incompatible with procreation. It produces vulnerability to attack from enemies. Sleep interferes with every voluntary adaptive motor act in the repertoire of coping mechanisms,” he said.

He pursued his research with characteristic intensity, studying the effects of sleep on various physiological functions, from exercise and mental stimulation to metabolism and stress. He worked primarily with animals, including rats and reptiles; Roth recalled once stumbling across a small alligator in a bathtub in Rechtschaffen’s lab on Drexel Avenue.

His research focused on what happens to animals when proper sleep is deprived or disrupted. In 1963, Rechtschaffen and Gerry Vogel, working with William Dement of Stanford, described narcolepsy--the first true sleep disorder--in a landmark paper. Later in 1968, Rechtschaffen and Anthony Kales of UCLA standardized the scoring system for human sleep stages, now known as the Rechtschaffen and Kales system, or simply R&K, which is still used by sleep laboratories worldwide today.

Rechtschaffen is perhaps best known for his landmark finding in 1983 that sleep is essential for survival. Researchers had long been trying to study the effects of sleep deprivation, primarily with rats, but the methods used to keep them awake, such as electrical shocks or dunking them in water, created additional stress and physical responses that confounded the intrinsic effects of lack of sleep. Rechtschaffen, working with Bernard Bergmann, devised a gentler apparatus called the disk-over-water method. An experimental rat would be placed on a round platform over a shallow pan of water, along with a control rat. When the experimental animal started to show signs of falling asleep, the disk began to slowly rotate. The animal had to walk to keep pace with it to avoid having its paws dipped into the water, thus staying awake. The control rat could continue sleeping whenever the experimental rat was awake.

Using this new technique, Rechtschaffen and collaborators showed that rats that were continuously deprived of sleep suffered severe health effects and died after about two weeks. Rats that were deprived of only REM sleep survived longer, but ultimately died as well. The rats also displayed a sharp drop in body temperature before they died. Rechtschaffen believed that this observation showed that sleep was essential for temperature regulation, although he never answered the question of the mechanisms underlying the lethal effect of sleep deprivation.

“If sleep does not serve an absolutely vital function,” he was fond of saying, “then it is the biggest mistake the evolutionary process has ever made.” 

Rigorous, charismatic, and intellectually generous

Allan Rechtschaffen was born in New York City and grew up on the Lower East Side, later moving to the Bronx. He received his BS and MA degrees from City College of New York and earned his PhD in psychology from Northwestern University in 1956. He was initially hired by the University of Chicago as a clinician in the Department of Psychiatry and was soon named Director of the Sleep Research Laboratory.

Known as a rigorous, organized, and charismatic researcher and teacher, Rechtschaffen’s work was supported by competitive grants from the National Institutes of Health for nearly his entire career. He trained 25 PhD students, many of whom are still active in the field today.

“Al was very interesting to talk with about all kinds of things, not just sleep,” said Samuel Refetoff, Professor Emeritus of Medicine, a friend and frequent collaborator. “He was very choosy about his friends and who he worked with, but he was just as critical of his own work as anyone else’s.”

He co-founded the Sleep Research Society with Dement in 1960, gathering the relatively small number of researchers in the field at the time to share ideas and paper abstracts. He later served as president of the society from 1979 to 1982 and received their Distinguished Scientist Award in 1989.

“He was a mensch,” said Eve Van Cauter, a prominent sleep researcher and Professor of Medicine Emeritus at UChicago, paying him the highest of compliments. “He was a great mentor and colleague, a person of integrity and honor to admire and emulate. His aura remains today as the wise person you always turned to for advice.”

In 1997, the New York Times Magazine described him as “an affable, intellectually generous man,” who, “looks as though his impending retirement were less a withdrawal than an embarkation.” Later, after he settled into retirement, he lamented to his wife, Karen, that perhaps he had retired too early because he still hadn’t answered the fundamental question of why we sleep.

Al and Karen raised three daughters: Laura, Katherine, and Amy. He loved being a father and grandfather to four grandchildren, along with uncle to countless nieces and nephews. He was famous for creations from his wood shop, and spent innumerable hours building gadgets to attract birds, just as he had spent countless hours working on his disk-over-water apparatus. In his retirement, he enjoyed playing bridge and spent winters in Arizona. The family intends to plan a memorial service in the new year.

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