Nature of sleep and lifespan changes - AO2

I - Babies sleep patterns are different to adults.

J - One suggestion as to why this may be is that babies' sleep is an adaptive mechanism that will make the parents life easier. For example, when a baby sleeps in the day, their parents can get the household chores finished that will enhance their survival.

E - This suggests that there is an adaptive mechanism in babies' that will enhance their survival.

I - The amount of REM sleep an infant has can be explained in terms of the immaturity of the brain.

J - Evidence shows that premature babies - whose brains are less mature - spend 90% of their time in active sleep.

E- This suggests that the younger the infant the more REM sleep they have because their brain is not as mature. 

I - Sleep patterns change in adolescence and this may be linked to hormone production.

J - Hormones are released at night so will disturb sleep patterns. This will lead to sleep deprivation which has similar signs to puberty. For example, irritability and moodiness. 

E - This shows that the hormones we produce as adolescents will change our sleep patterns.

I - It is commonly thought that a good night's sleep in related to good health. 

J - Kripke et al (2002) surveyed over one million adult mean and women and found that people sleeping only six hours a night had a reduced mortality risk, whereas those that were sleeping for an average of eight hours a night had a 15% increase in the risk of death. 

E - However, this is corelational data so there may be extraneous variables that cause the link between sleep duration and mortality rates. 

I - Reduced sleep in old age can be explained in terms of problems staying asleep.

J - In old age SWS is reduced so they are more easily woken. As SWS is reduced, it leads to reduced production of growth hormone. 

E - This can explain some of the symptoms associated with old age.