We all know that groggy, unfocused feeling after a sleepless night — but what’s really happening inside the brain?
New research from MIT reveals that during moments of lost attention caused by sleep deprivation, the brain briefly slips into a sleep-like cleaning mode.
The study, published in Nature Neuroscience, found that waves of cerebrospinal fluid (CSF) — the liquid that clears out toxins and waste — flush in and out of the brain during these lapses. This fluid movement is usually seen only during deep sleep.
“When you don’t sleep, these CSF waves start to intrude into wakefulness,” said Laura Lewis, the study’s senior author and associate professor at MIT. “They come with an attentional tradeoff — your focus fails when the brain triggers this cleaning process.”
To uncover this, researchers observed 26 volunteers performing attention tests after a night of sleep deprivation and again after normal rest. Using EEG and fMRI scans, they tracked brain waves, CSF flow, and physiological signals like heart rate, breathing, and pupil size.
Sleep-deprived participants reacted more slowly and often missed cues altogether. During each lapse, the team saw a pulse of CSF flowing out of the brain — and back in when attention returned. These waves were also synchronized with slower breathing, lower heart rate, and shrinking pupils, suggesting a coordinated brain-body response.
The findings indicate that the brain, desperate for rest, tries to sneak in micro “maintenance sessions” while awake — a costly tradeoff that restores some function but sabotages focus.
In short, if you don’t let your brain rest at night, it might just force a mini nap on you during the day.
Also Read: International Sleep Day 2024; Eight Foods for Better Sleep https://www.vibesofindia.com/international-sleep-day-2024-eight-foods-for-better-sleep/
