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Are Heavy Sleepers Smarter Than Light Sleepers?

Are you a sound sleeper? Do your friends make fun of the fact that you can sleep through anything? Well, the jokes on them because research shows that deep sleepers have busier brains.

The frequent bursts of brain activity are called sleep spindles. Researchers hope the study will help give light-sleepers a chance to sleep soundly.

When Do Sleep Spindles Occur?



Sleep spindles occur only during sleep. Since the 1930s, scientists have been researching their relationship to the brain.

In the 1990s, scientists found the source of spindles: the thalamus. The thalamus controls sleep and helps process sensory information to the cerebral cortex. This was the first time a link between sleep and brain activity had been found.

An Unusual Study



The sleep spindle study involved 12 people who spent 3 nights in the lab. The participants were given soundproof rooms with comfortable beds and asked, simply, to sleep.

Throughout the first night, researchers only measured their brainwaves. Over the next two nights, researchers began to play sounds that would awaken the participants from their slumber.

Comparing Results



Researchers took the participant's spindle production numbers (ranging from 3-6 spindles per minute) and compared them with the sound volume used to awaken the participants.

They found that sleepers with higher spindle rates were less likely to wake up. They believe that spindles indicate when the thalamus is blocking sounds from reaching the cerebral cortex and waking the participants.

The Future



Sleep researchers hope that this study, and future studies using sleep spindles, will help those with insomnia and other sleep disorders.

Read More:



  • Busy Brains Make for Deeper Sleep (Science)
  • Spontaneous brain rhythms predict sleep stability in the face of noise (Current Biology)




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