MIT researchers have proven that regions of the brain can take a snooze even while you’re conscious. The team of neuroscientists have figured out that a circuit originating in the thalamic reticular nucleus (TRN) can cause individual sections of your brain to either become less alert or fall completely asleep, independently of the regions surrounding it. It goes some way to explaining why many of us occasionally zone out during conversations.
“Until now, most sleep research has focused on global control of sleep, which occurs when the entire brain is awash in slow waves — oscillations of brain activity created when sets of neurons are silenced for brief periods,” reads the report. “The researchers believe the TRN fine-tunes the brain’s control over local brain regions, enhancing or reducing slow waves in certain regions so those areas can communicate with each other, or inducing some areas to become less alert when the brain is very drowsy.”
The group used optogenetics to reach its conclusion, using DNA from algae to make mice brains react to light. They then used lasers to target various parts of the brains, recording their findings. We've long known that certain animals, such as ducks and dolphins, are able to rest one part of their brain independently from the other, but humans were previously believed to fall into the all or nothing category.
Intriguing as this is, what does it all actually mean? In short, insomniacs should be buzzing. The breakthrough could lead to the development of drugs that could induce a more natural-feeling, non-REM-like sleep. [MIT]