oswald’s restoration theory of sleep

Question 1

What is oswald’s restoration theory of sleep

Answer 1

This is a biological theory that argues all animals (including humans) sleep in order for the body and brain to carry out essential repair tasks.

Question 2

What did oswald argue?

Answer 2

Oswald argued that since sleep appears to be universal and hasn’t changed through evolution, it must serve an essential purpose.

Question 3

The theory states that during sleep?

Answer 3

-The body carries out repairs to cells

-Resources of energy are restored

-Waste chemicals that have built up during the day are removed

Question 4

What does the theory argue?

Answer 4

Specifically, the theory argues that non-REM sleep is important for restoration of the body and REM sleep is important for restoration of the brain.

Question 5

Savard et al (2003)

Answer 5

Savard compared the immune function of those with a normal sleeping pattern and those with chronic insomnia. He found that normal sleepers had a much higher level of immune cells than those with insomnia, supporting the idea that sleep is important for the repair of cells in the body.

Question 5

Rechstaffen et al (1989)

Answer 5

Researchers deprived rats of sleep and measured the effects. After a week of sleep deprivation, the rats began to lose weight despite eating more. Over the next four weeks, body weight plummeted, body temperature became unstable and the rats eventually died. This evidence supports the idea that the rats were unable to restore their bodies properly due to the lack of sleep.

Question 6

Shapiro et al (1981)

Answer 6

This was a study of ultramarathon runners. After an ultramarathon, Shapiro found that runners slept on average 90 minutes longer than usual for the next two nights. Particularly, their non-REM sleep increased. This suggests that runners needed more sleep, and especially more non-REM sleep to help restore their physiological functions after strenuous exercise. This study supports the restoration theory of sleep.

Question 7

Strengths of Restoration Theory

Answer 7

-Restorative theory is further supported by the evidence that other restorative functions such as muscle growth, tissue repair and growth hormones occur mostly during sleep.

-This is a key explanation of why all mammals require to sleep, despite a long period of evolution. If sleep isn’t essential, we wouldn’t do it.

Question 8

Weaknesses of Restoration Theory

Answer 8

• Restorative theory is over-simplistic and reductionist to suggest the only purpose of sleep is restoration. We know there are multiple different stages and therefore sleep probably has multiple functions.