A medical doctor, Jouvet was a Professor of Experimental Medicine at the University of Lyon, France. In 1953, Eugene Aserinsky of the University of Chicago had discovered “rapid eye-movement” (or REM) sleep: according to an EEG machine, a sleeping subject appeared to be awake and looking around, yet Aserinsky could see the subject was definitely asleep and motionless. Adult humans spend about 20 percent of their sleep in REM; babies around 50 percent. While eventually Aserinsky and other researchers associated REM sleep with the most active phase of dreaming, they weren’t sure why. That’s the question Jouvet took up. First, Jouvet proved that REM sleep also occurred in other mammals. He also discovered that the pontine tegmentum, or dorsal pons, a structure located within the brainstem, controlled the stages of sleep. Further, he found that the medulla oblongata, another structure in the brainstem, created “atonia” — a full paralysis of voluntary muscles — during REM sleep. Why? So that animals, including humans, wouldn’t physically act out their dreams. Jouvet showed (while working with cats) that a sleeping subject with a damaged medulla would still dream, but rather than lying still, would jump up and move around, even though it was still asleep. The combined impact of these discoveries was actually fairly Earth-shattering: sleep had previously been considered simple unconsciousness, and certainly not worthy of study (what, waste miles of expensive graph paper on an EEG machine recording “nothing”?!)
With Jouvet’s discoveries, it was now clear our brains were actively working on something during sleep — at least during the 90-minute cycle between REM and “non-REM” sleep. Jouvet dubbed the active REM time “paradoxical sleep”: the subject is sleeping, and paralyzed, but his brain is working hard. This represented, he argued, a third state of being, actually separate from “awake” and “asleep.” Working hard doing what? Something that was important enough to paralyze the sleeper, which makes them more susceptible to attack by predators. Further, after being deprived of REM sleep, an animal will go into “REM rebound” afterward — getting extra REM sleep to make up for the deprivation. Obviously, then, REM is extremely important: but what does it do? Suddenly, sleep was very worthy of study, and Jouvet, along with Aserinsky and another grad student in his lab, William Dement, now of Stanford Medical School (and their advisor, Nathaniel Kleitman), are considered pioneers in sleep research. Jouvet dismissed Freud’s theory: that dreams reveal insight into hidden desires and emotions. Rather, his own controversial theory is that we dream “to preserve our individuality.” That is, he says in his 2001 book The Paradox of Sleep: The Story of Dreaming, dreams function to help our brains: they are a type of “iterative genetic programming” — an exercising of our basic instincts like fight or flight, continuously reinforcing our internal patterns and responses. Still, the question wasn’t entirely settled when Dr. Jouvet died, on October 3, at 91.