Restoration theories of sleep
AO1- The theory
Oswald (1980) proposed an early restoration theory. He argued that REM sleep allows the restoration of and
reorganisation of the nervous system. NREM sleep involves the restoration and repair of the body through release
of growth hormone. Growth hormone is released from the pituitary gland in small bursts throughout the day, but it
is released in larger amounts during stage 4 sleep. So, stage 4 sleep is particularly necessary to the repair of the
body.
Horne (1988) said that sleep was needed for psychological recovery. He distinguished between core sleep (stage 4
and stage 5) and optional sleep (stages 1-3 ). He argued that core sleep is critical for normal brain functioning
because during it the brain restores itself after the activities of the day.
AO2- Evaluation of the theory
IDA- Practical applications
Sleep deprivation evidence
Fill out the boxes explaining whether the sleep deprivation evidence lends any support to the theory and/or whether
it challenges the theory in any way.
Study
Peter Tripp
Randy Gardner
Michael Cork – fatal
familial insomnia
Which restoration theory it supports and why
Other research evidence
Sharpio et al (1981) found that runners who had taken part in an ultra marathon covering 57 miles slept about an
hour and a half longer than normal on the two nights following the marathon. In addition, there was a much larger
proportion of time devoted to stage 4 sleep. Empson (1989) noted that the disruption of stage 4 sleep in healthy
people resulted in stiffness in the back and muscle pain.
Ground the evidence to restoration theories; remember to state which part of the theory they support
Dement (1960) compared participants who had been deprived of REM sleep with a control group who had been
deprived of the same amount of NREM sleep. He found that the REM deprived group were more irritable, more
aggressive and unable to concentrate on various tasks. Borbely (1986) found that REM deprived individuals made
31 attempts to re-enter REM on the first night of deprivation, 51 attempts on the second night and over 60 attempts
on the third
Ground the evidence to restoration theories; remember to state which part of the theory they support
AO3
Wider evaluation- Oversimplified theory