Why do we sleep?

There are many theories about why we sleep and dream, and many of these involve memory in some way (including Freud’s theory of why we dream). A relatively recent theory has been gathering support, variously called synaptic renormalisation hypothesis or synaptic homeostasis hypothesis (aka ‘SHY’ – first proposed by Tononi and Corelli, 2003). The basic […]

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Shift work and heart attack

In our A2 Complete Companion we reported a study by Knutsson et al. (1986) who found that shift workers were three times more likely to develop heart disease than non-shift workers. A study just published by Hackam et al. ( 2012 ) confirms this, claiming a 24% increased risk of a coronary event and 5% increased risk of stroke. […]

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The Myth of the eight-hour sleep

Today’s BBC website carries a fascinating article that challenges the commonly held view that an eight-hour period of continuous sleep is natural for human beings. We often worry about lying awake in the middle of the night – but it could be good for you. A growing body of evidence from both science and history […]

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It seems that dolphins don’t dream

In Chapter 1 (Biological rhythms and sleep) of our A2 Complete Companion there is a contradiction (kindly pointed out by Ruth Bailey of Akeley Wood School). On page 13  the text says that dolphins don’t have REM sleep whereas on page 14 the graph indicates a significant amount of REM sleep in dolphin. So which […]

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