sleep across the lifespan

Question 1

newborns - 2 months

Answer 1

• no regular rhythm or concentration of sleeping and waking periods
• duration tends to be irregular and one episode may from 30mins to 4 hours
• first few weeks , more than half of the infants sleep is in REM sleep
  -Sleep onset also occurs through REM sleep, not NREM
• each sleep episode consists of only one or two cycles,
• young infant’s circadian
  rhythms are not fully developed and have not yet been fully entrained to the daily day–night
  cycle of their external environment.

Question 2

3 months - infants

Answer 2

• NREM–REM sleep cycles become more regular
• Sleep onset now begins with NREM stage 1
• REM sleep decreases and shifts to the later part of the sleep cycle
• total NREM–REM sleep cycle is typically 50 to 60 minutes.

Question 3

6 months - infants

Answer 3

• total sleep time reduces slightly
• Sleep episodes therefore become less fragmented.
• The muscle
  paralysis typical of REM sleep has also set in.
• 5 to 8 hours

Question 4

12 months - infants

Answer 4

• infant sleeps 14 to 15 hours per day (day and night)
• proportion of REM sleep is still
  relatively high compared with childhood, adolescence and adulthood.

Question 5

children

Answer 5

Total sleep time decreases to 10-12 hours
- this is due to biological and social factors
- The proportion of REM sleep decrease(20-25%) and the amount of NREM sleep increases (75-80%), with a greater percentage of sleep time spent in stages 3 and 4.
- slow wave deep sleep of young children different from adults which cause them to skip their first REM period of sleep

Question 6

adolescent

Answer 6

• rem sleep (18.5-20%) and nrem (80-81.5%) in NREM
• total amount of sleep 9 hours
• mid adolescents, first rem period is skipped
• Within NREM sleep, the time spent of stages 3 and 4 sleep progressively declines and the time spent in stage 2 increases.
• the amount of slow wave deep sleep has decreased by nearly 40% since early childhood.

Question 7

adults

Answer 7

• average about 8 hours of sleep a night,
  -20–25% of which is REM sleep adn 75-80% is NREM
• (between the ages of 20 to 60), deep sleep declines at a rate of about 2% per decade.
• after 60s, the decline is sever, having stage 3 even disappear
• Sleep also tends to become more fragmented as we age, with more nighttime awakenings among older adults.

Question 8

elderly

Answer 8

• Older people also tend to become sleepier in the early evening and wake earlier in the morning
  compared to younger adults.
• 20-23% of sleep is spent in REM and 77-80% is spent in NREM
  -spend 6-7 hours of total sleep
• SLEEP ORDERS ARE PREVALENT IN OLDER ADULTS

Question 9

newborns and infants

Answer 9

• 50% of total sleep is spent in REM and the other 50 is spent in NREM
• new borns spend 16 hours in a day asleep and children spend 14-17 hours asleep
• sleep onset can occur without regular concentration of sleeping
  episodes last from 30 mins to 40 hours

Question 10

what is the percentage of REM sleep decreases as we age

Answer 10

from 40% in the first few months to 30% by 18 months and then around 20% through adulthood