After years of research trying to determine exactly what the mechanisms are that cause us to fall asleep, a 39-year old neurologist from Harvard Medical School and his team of researchers believe that they have come up with the solution. In a study that was recently published in the journal Nature Neuroscience, Patrick Fuller outlines his discovery, which identifies a tiny, recently-discovered section of the brain that not only appears to control whether we sleep, but also the most basic operation of our lungs, heart, and other bodily functions. He and his group have named this area the parafacial zone.
Fuller began his research by reviewing neurological studies that have been done since the 1950s, which was when the idea first arose that there might be a specific area of the brain that controls deep sleep. Since that time sleep studies have clarified the role that upper brain structures play in “slow-wave sleep”, which is when our memories are organized and consolidated and the body restores the immune system. That part of the brain is also responsible for how we feel when w wake up. But slow-wave sleep does not represent all of our sleep – in fact, it only represents about half of our deep sleep, and that means that the rest of it is controlled somewhere else. All of the sleep-aid medications that have been developed over the years have targeted these upper brain structures, and Fuller says, “What people forget is that almost the entire brain stem is wake-promoting.”
Working with colleagues from Harvard as well as a group of researchers at the University of Buffalo, Fuller devoted three years of research into finding an area of the brain that they theorized must exist – a group of brain stem neurons that they weren’t sure existed. The way that they conducted their investigation was by injecting a harmless virus into different section of lab animals’ brains and then watching them to see how they responded. They noted that a mouse whose brain had been infected with the virus in a lower section of the brain that had been previously unexplored was remaining alert and awake for periods that exceeded those of other mice. Because the area is close to the facial nerve, they named it the parafacial zone as they conducted further experimentation.
What the group discovered was that not only could they make the animals stay up longer by stimulating that area of the brain, but they could also make them fall asleep by using a different virus that flooded the area with GABA, the neurochemical that makes us fall asleep. What this means is that in identifying this important structure, researchers can now design medications that target the area for drug delivery so that humans can benefit and insomnia can be effectively treated. The research is expected to take between five and ten years.