Resoration Theory Flashcards
Growth hormone
This is secreted during SWS. It enables protein synthesis and cell growth. Sassin found that when sleep-wake cycles are reversed. Showing GH is controlled by neural mechanisms. Further evidence comes from research which found that the amount of GH correlates with the amount of SWS. And the decline of GH also has been associated with reduced SWS.
Oswald said what?
That all sleep is essential for repair and restoration. With REM enabling brain recovery and memory consolidation. SWS releasing growth hormone that stimulates growth. And NREM is a time for replenishing the body. Sleep is an ideal time to remove waste and to restock/replenish its levels of neurotransmitters and to synthesize proteins.
Body weight
Oswold’s theory is supported by correlational research conducted by Adam who found there was a correlation between sleep time and body mass. If you have more body mass, you are likely to have higher sleep time. However, this research is correlational and doesnt account for a third variable which may be apparent.
Oswolds theory is also supported by Rechtschaffen
who found that rats who were spun on a turntable to prevent them from sleeping often dies of at least suffered ulcers and internal bleeding. However, this could be due to other factors sch as the stress of it.
Oswold is also supported by Lugaressi
who studied a man who could hardly sleep due to damage in the brain. He couldn’t function properly and eventually died. However, anxiety could cause the lack of sleep due to his condition.
Shaprio also supported Oswold
He provided further support. He studied marathon runners. It was found they slept for 90 minutes longer over the next 2 nights because more repair work was needed on their bodies. NREM sleep increased while REM decreased.
There is a lack of support for lack of exercise reducing the amount of deep sleep
The model would predict this but there is a lack of support. A study by Ryback and Lewis got students to spend 6 weeks in bed and observed no change in their sleep patterns
What is the main difference between Oswold and Horne?
Horne believes that body restoration is not the only function of sleep but instead this occurs during periods of wakefulness, leaving core sleep to provide for the restoration of brain systems,
What is a limitation of Oswold using amino acids?
Amino acids stay in out bodies for 4 hours after we consume them as protein. So why do we need to sleep for so long if proteins are only used for 4 hours. For more than restoration purposes?
How is Peter Tripp used as a strength of Oswold?
He stayed awake for 8 days and nights, he experienced a drop in body temperature, hallucinations,losing hold on reality, hearing voices and being unable to recover his sense of gravity. However, demand characteristics could have played a part which him conforming to side effects hes been told he might experience and because it is a case study, you cannot generalise.
What is the link between Oswold and Horne?
Randy Gardner spent 11 days with no sleep and suffered nowhere near the same effects Tripp did. His symptoms were only psychological. Horne build off Oswold’s theory to include REM restoration where neurotransmitters are replenished. During deprivation, problems in perception, memory and attention would be explained by loss of these neurotransmitters. However, highly motivated individuals act differently and so this might account for the differences in Tripps and Gardners studies.
Horne
Core and Optional sleep
Horne distinguishes between core and optional sleep. Core sleep appears to be present and essential in all species whereas optional appears to not be so vital.
Horne
REM sleep is essential
Dement deprived volunteers either of REM sleep or NREM sleep and observed the consequences, He found that REM deprivation was most dramatic with participants becoming more aggressive ans having poor concentration. He also reported REM rebound effects e.g. going straight into REM sleep when given the chance. By the 26th night, thy were averaging 26 attempts per night to enter REM
Horne REM sleep is essential-cats
Jouvet placed cats on an upturned flower pot in water. When the cats fell into REM sleep, their muscles would relax and they would fall in the water waking them up. After numerous times, the cats became conditioned. On reaching REM, they would wake up before falling into the water. Eventually all the cats died. However, could thus just be due to lack of REM sleep or stress due to falling in the water?
Horne- baby’s sleeping patterns
A baby spends around 50% of its sleep in REM sleep, consistent with the uses its needed for brain development and growth