What happens while you sleep?
Ever found a simple task harder after a restless night? Your nights and your days are closely connected.
Is your brain switched off during sleep?
Read the explanation
Your brain remains active during sleep. It helps process new information and supports memory. Sleep also helps your body recover.
Notice the difference the next day.
Open each window to see a different part of the story.
01Remembering & concentrating
Learning a name, following a conversation, making a decision: sleep supports attention and memory. Too little sleep can make these everyday tasks harder.
02Managing feelings
After a difficult night, small frustrations can feel bigger. Sleep supports emotional wellbeing; stress and low mood can also make sleep harder.
03Recovering & staying well
Sleep supports tissue repair, immune function and the processes that regulate hormones and energy use. Over time, insufficient sleep is linked with poorer health.
Sleep comes in cycles.
Lighter and deeper sleepREM
Active brain, often dreaming
You move between non-REM and REM sleep several times. Deep sleep tends to be more prominent early in the night; REM periods tend to be longer later on. Brief waking between cycles can happen.
After a short night, Sam feels awake but keeps losing track of a conversation. What could explain it?
Read the explanation
How awake you feel does not always tell you how well you are performing. Short sleep can affect attention, memory and reactions; other factors may also contribute.