Theories of sleep Restoration (Oswald; Horne) The function of sleep is to allow body to be repaired and restored Oswald (1980) – REM for brain; SWS for body Horne (1988) – core sleep (REM & SWS) vs. optional sleep – sleep deprivation leads to recovery https://simplypsych.wordpress.com/2014/02/14/outline-and-evaluate-restoration-explanations-of-the-functions-of-sleep-416-marks/ psychlotron.org.uk

Restoration theory Main predictions: Deficits in functioning during sleep deprivation Rebound following deprivation Increase in REM during brain growth, reorganisation & repair Increase in SWS during illness, recovery from injury psychlotron.org.uk

CORE SLEEP Concentrated in stage 4 slow wave sleep (SWS) and in REM SWS – lighter sleep – Oswald believes SWS restores body to full waking capacity. Horne does not believe this – he believes this occurs during periods of relaxed wakefulness.

Effects of sleep deprivation Animal studies tend to support restoration Prolonged sleep deprivation causes immune failure & death Studies of humans produce less clear-cut results Confounding effects of stress etc. psychlotron.org.uk

Rebound Generally, people catch up on sleep following deprivation Not all lost sleep is reclaimed About 70% of lost SWS and about 50% of lost REM typically recovered Only some sleep is necessary psychlotron.org.uk

Illness & injury Sleep does increase during illness and recovery from injury Total sleep time increases during illness REM increases during recovery from brain injury, ECT & drug withdrawal SWS deprivation can cause physical symptoms psychlotron.org.uk

Evaluation Much evidence is consistent with the restoration view Main problem comes from apparent lack of serious biological malfunction during sleep deprivation in humans. https://simplypsych.wordpress.com/2014/02/14/outline-and-evaluate-restoration-explanations-of-the-functions-of-sleep-416-marks/ psychlotron.org.uk