Lifespan and sleep
Sleep differs throughout different stages of life. Babies sleep a lot more than children; they also have very short sleep cycles, meaning that they only sleep for about an hour each time. Infants have more sleep than babies, they have similar sleep patterns to adults, but slightly more immature versions, and with around half of an infant’s sleep is REM sleep. It has been suggested that the amount of REM is related to the immaturity of the brain. This is supported by the fact that premature babies have around 90% REM sleep, which is 40% more than other babies. This shows that there may be a correlation between the immaturity of the brain and REM sleep.
By the age of 5 it is known that children have already developed EEG patterns similar to adults. However they sleep more than most adults, around 10 hours and day, they also have more REM sleep (around 30%). It is also common that a child will suffer from sleep disorders such as Sleep walking.