Researchers at the University of Bern have shown that a single area of the brain – the thalamus – is responsible both for the actions of falling asleep and waking up.
Previously, the university said, although the thalamus was known to be important for sleep quality, consensus was that the impulses for falling asleep and waking up took place in separate regions of the brain.
However, a Swiss research team led by Antoine Adamantis now claims that the thalamus area plays a double role.
Using optogenetic techniques to activate brain neurons with light impulses, they found that a small group of neurons in this area produces long waves that can help with falling asleep, while the same neurons also produce the ‘signal’ to wake up.
The thalamus, located between the cortex and the brainstem, is a linking region that also plays a role in processing sensory input and organizing cognition and consciousness. It is connected to practically all other regions in the brain.
Crucially, using experimental data drawn from tests on mice, the researchers also found that when the thalamic neurons were inhibited, sleep quality and recovery also suffered.
At a time when the active population is sleeping less than ever before – 20% less than 50 years ago, they say – this discovery could have implications for efforts to improve quality and consistency of sleep.
The results were published in the Nature Neuroscience magazine.