New studies have shown that while we sleep, our neural connections shrink—by 18-20% (according to one study) when compared to waking time. Why? Researchers think it’s because our neurons need time to “downscale”—becoming weaker for a time to prevent becoming too saturated and unable to learn new things. In fact, they argue, this may be one of the primary purposes of sleep—to prepare our neurons for a new day of learning.
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