Why We Sleep And Dream

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Sleep is the natural resting state in which your body relaxes, your eyes close, and your brain shifts into special activity patterns that are very different from being awake. Humans spend about a third of their lives asleep because it is when the body repairs itself and the brain organises what it has learnt. Far from being 'switched off', a sleeping brain is busy doing important work.

During sleep the body recharges its energy, repairs muscles, and grows, while the brain sorts through the day's memories — keeping what matters and clearing out the rest. Sleep moves through repeating cycles of lighter and deeper stages, including REM sleep, the stage where most dreaming happens as the brain mixes memories and feelings into stories. Children in Singapore need more sleep than adults — typically 9 to 12 hours — and simple habits like a calm bedtime routine and less screen time before bed help them fall asleep well.

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Frequently asked questions

Why do we need to sleep at all?
Sleep lets the body recharge its energy and repair itself, and it gives the brain time to sort and store the day's memories. Without enough sleep we feel tired, find it harder to concentrate, and learn less well.
Why do we dream?
Dreams mostly happen during REM (rapid eye movement) sleep, when the brain is very active and playful. Scientists think dreaming helps the brain process memories and emotions by mixing them together, which is why dreams can feel strange or jumbled.
How many hours of sleep does a primary-school child need?
Children aged 6 to 12 generally need about 9 to 12 hours of sleep each night — more than adults, who usually need 7 to 9 hours. Growing bodies and busy learning brains use the extra rest to develop.
What are the stages of sleep?
Sleep happens in repeating cycles that move from light sleep into deep sleep and then into REM (dream) sleep. The body cycles through these stages several times each night, with deep sleep helping the body repair and REM sleep helping the brain.
What helps a child fall asleep well?
Calm, regular habits help most: a steady bedtime, a quiet dark room, and a wind-down routine. Bright screens, exciting games, and sugary drinks close to bedtime keep the brain too awake and make sleep harder.

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