Your Brain on Sleep: What Happens in the Hours You Don't Remember
While you sleep, your brain files memories, clears waste and rehearses the day. Skimping on it costs more than a slow morning.
Sleep is not the brain switching off. Brain scans show distinct phases through the night, each with its own job.
Filing and cleaning
In deep sleep, the brain replays the day's experiences and moves important memories into long-term storage. Fluid flushes through brain tissue, clearing proteins linked to dementia.
Dreaming sleep, which comes in longer bursts towards morning, appears to help with emotional processing and creative problem-solving. Cut your night short and that is the stage you lose.