Read more: "The night: The nocturnal journey of body and mind"
THE transformation starts while you are still awake. Just before bedtime, body temperature plummets almost half a degree from its mid-evening peak. Melatonin, a sleep-promoting hormone, surges in response. Suddenly, the pressure to sleep that has built throughout the day no longer encounters the resistance of a high body temperature, and waves of fatigue assail you.
This isn't just your body priming you for a good night's rest. In some ways, it is preparing you to become a whole different creature, because the night-time body has functions and a character all its own. If night never ended, we would hardly recognise what we become.
The moment you succumb to sleep's inexorable pull, your body temperature drops. The lower body heat slows chemical reactions, setting the ...
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