By 1 year infants
sleep mainly at
night, with some
naps during the day
Periods of deep sleep
lengthen and there is
reduction in REM sleep
Evaluation
Daytime sleep adaptive
mechanism - makes life easier
for parents
REM sleep linked to
production of neurotransmitters
and consolidation of memories
Childhood
By age 5 children have EEG
patterns that look like those of
an adult but they sleep more (12
hours a day)
Still more REM activity
than adults (30% of sleep
time)
Boys sleep more than girls
Not uncommon for children to
experience parasomnias such
as sleep walking or night terrors
Adolescence
Need for sleep increases slightly
from childhood: 9-10 hours a night
Circadian rhythms change so teenagers feel
more awake later at night and have phase delay
(more difficulty getting up early)
Evaluation
Change in sleeping pattern
Hormones primarily released at night
Real world application
Wolfson and Carskadon (2005)
Recommended school
should begin later
Adulthood
Sleep 8 hours a night
25% REM sleep
Parasomnias less likely but other
sleep disorders such as insomnia
is more likely
Older people have more
difficulty going to sleep and
wake up more frequently
Evaluation
Kripke et al. (2002)
Nota:
Surveyed over 1 million adult men and women and found that people sleeping for only 6 or 7 hours had a reduced mortality risk, whereas those sleeping 8 had a 15% increase in risk of death, and over 30% for people who slept 10 hours. However, there may be other factors affecting this such as underlying illness
SWS sleep is reduced in
old age explaining why
older people are more
easily woken
Van Cauter et al. (2000)
Nota:
Less SWS means less growth hormones which explains lack of energy and lower bone density in older people