Dolphins, ducks, and fur seals can put half the brain into deep sleep while the other half stays awake and watching for predators. Chiara Cirelli's lab at the University of Wisconsin-Madison wondered whether you could force that trick in an animal that doesn't do it naturally — and, as New Scientist reports, get some of sleep's benefits without the sleep. Their study in Nature Neuroscience suggests you can, at least in mice.
During deep NREM sleep, the cortex fires in unison and then goes quiet, a slow-wave pattern tied to the brain's overnight decluttering of neural connections. The researchers engineered mice whose neurons could be switched with light, kept them awake for five hours, then pulsed one hemisphere for 30 minutes.
"Because that small part of the brain did its decluttering while awake, it no longer needed extra deep sleep afterwards," Cirelli said. Sleep-deprived mice that got the stimulation matched well-rested ones on a memory test. The team wants to try it in people with non-invasive transcranial stimulation.
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