What is worse for your mood – interrupted sleep or shortened sleep? © Getty Images

What is worse for your mood – interrupted sleep or shortened sleep?

We’d also argue that being hooked up to lab equipment is not conducive to a good night’s rest.

Asked by: Susie Rees, Lamberhurst

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Interrupted sleep. At least, that’s what one recent study shows. We’ve long known that sleep deprivation makes people bad-tempered and miserable, and that insomnia is linked to depression, but exactly why is less certain.

When volunteers slept in a lab and reported their mood every day, some were made to go to bed later than usual while others had their sleep interrupted several times. Both groups had the same total amount of sleep but the interrupted sleepers reported worse changes in mood. The researchers concluded that a lack of slow-wave sleep, which is the deepest type of sleep, was to blame.

But don’t jump to conclusions. These interruptions may be like being woken by a crying baby or a snoring partner. They break into your sleep cycle unpredictably at random times, therefore disrupting the normal sleep pattern. But if you regularly wake up yourself in the night you are probably waking at the end of each cycle and this would not have the same detrimental effect on your slow-wave sleep.


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