Scans revealed a wave of cerebrospinal fluid being expelled from the brain moments after attention dropped and returning a second or so after the lapse ended. Such waves are normally seen in deep sleep and are thought to help the brain flush out metabolic waste that builds up during the day.
Other measurements showed that the pupils of people’s eyes constricted about 12 seconds before the fluid left the brain and returned to normal after the lapse. Breathing and heart rate also fell, the researchers report in Nature Neuroscience.
While more questions remain, the lapses seem to happen when the brain tries to juggle normal cognitive functioning with essential maintenance that is normally carried out during sleep. “It’s your brain trying to take a break,” Yang said.
Study finds lapses of attention in sleep-deprived people coincide with wave of fluid flowing out of the brain
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