The history of the science of sleep
Only since the turn of the 20th century and the development of ways to measure brain activity during sleep has sleep begun to be more widely understood. The 1950s heralded what is now a standalone discipline—the science of sleep.
The mystery of sleep has been of interest to physicians, scientists, and philosophers as far back as around 350 BCE, when the Ancient Greeks considered sleep to be a type of physiological state somehow related to digestion. Since the discovery of sleeping brainwaves in the 1930s, the science of sleep has progressed at great speed, with huge advances and achievements in our understanding of the mechanics of sleep.
THE SIMPLE TRUTH ABOUT SLEEP | The history of the science of sleep
Timeline of key discoveries in sleep science
1845
First connection made between human body temperature and sleep patterns
1888
Data documenting narcolepsy first published
1899
Sigmund Freud’s Interpretation of Dreams is published, outlining a theory of dream analysis
1922
Identification of hypothalamus as the area of the brain responsible for regulating sleep/wake cycles
1937
Using recording of brain waves by electro-encephalogram (EEG), five sleep stages identified
1950s
Polysomnography—an in-depth sleep study practice—established, using EEGs and other markers
1951–1953
Discovery of rapid eye movement (REM) sleep, a light sleep phase in which vivid dreams occur
1956
Obstructive sleep apnea (OSA) first described and classified
1972
The suprachiasmatic nucleus (SCN), in the hypothalamus, identified as seat of the circadian clock
1971
Period gene (PER) identified as playing a role in the timings of behaviors such as waking in circadian rhythm
1970
First sleep laboratory focusing on sleep disorders opens at Stanford University
1966
“The bunker experiment” indicates a natural 24-hour rhythm exists even when not exposed to daylight
1962
The pons region of the brain is identified as controlling REM sleep
1960
The term “zeitgeber” coined to describe external cues the body uses to synchronize its circadian cycle
1959
The term “circadian” (Latin for “about a day”) first used to describe the body’s sleep/wake rhythms
1958
Discovery of the hormone melatonin as being responsible for regulating the sleep/wake cycle
1973
Cognitive Behavioral Therapy (CBT) first used as a treatment for insomnia
1979
Treatment known as continuous positive airway pressure (CPAP) for sleep apnea is first used
1982
Two-process model of sleep homeostasis (Process S) and the circadian clock (Process C) proposed
2003
Theory proposed linking homeostatic sleep regulation to learning
2005
US National Institute of Health suggests CBT as the first-line treatment for insomnia
2009
DEC2 gene discovered showing that short sleep duration is genetic for those with this mutation
2017
Nobel Prize awarded to a team that uncovered molecular mechanisms controlling the circadian rhythm
2017
Discovery of “insomnia gene” Crypto-chrome 1 (CRY1), which can disrupt the body’s natural rhythms