Neonatal period (1-15 days)
during this period, sleep duration is the highest it will ever be in the lifespan. New- born babies sleep for approx. 16 hours.
Approximately 50% of the sleep episode is rem sleep and approximately 50% is NREM sleep.
Infancy (3-24 months)
Sleep duration decreases to approximately 13.5 hours.
The proportion of REM and NREM sleep also changes to approximately 35% REM and approximately 65% NREM sleep.
Time spent in REM sleep is significantly high because newborns and infants are experiencing rapid brain development. (neonatal period and infancy)
Childhood (2-14 years)
Sleep duration decreases again to approximately 11 hours.
The proportion of NREM sleep increases slightly to 80% of the sleep episode, while REM sleep decreases to approximately 20% of the sleep episode.
Time spent in REM sleep starts to reduce as the pace of the brain development steadies
Adolescence (14-18 years)
Sleep duration decreases to 9 hours
The proportion of REM and NREM sleep remains fairly constant at 20% REM and 80% NREM sleep.
Adolescence experiences a biological delayed sleep onset by 1-2 hours, meaning they are more likely to become sleepier later and wake up later.
Young adulthood (18-30 years)
Sleep duration decreases again to approximately 7.75 hours.
The proportion of REM and NREM sleep remains fairly constant at 20% REM and 80% NREM.
Middle adulthood (30-75 years)
Sleep duration remainds at approximately 7-8 hours
The proportion of REM and NREM sleep remains fairly constant at 20% REM and 80% NREM.
Old age (75+ years)
Sleep duration continues to decrease to approximately 6 hours.
The proportion of REM and NREM sleep remains fairly constant at 20% REM and 80% NREM.
Older adults tend to experience advanced sleep phase syndrome, which is a biological shift forward in their sleep-wake cycle, meaning they become sleepier earlier and wake up earlier.
