3 ms·
From other articles I've read, there is some evidence to suggest that without artificial light, humans tend to break sleep into two periods--waking up in the mi
by learc83 14y ago
From other articles I've read, there is some evidence to suggest that without artificial light, humans tend to break sleep into two periods--waking up in the middle of the night for a few hours.
Also drinking water before you go to sleep works as a natural alarm clock.
- rayiner 14y agoI wonder how much of that is because of babies back in a time before widespread birth control. I break sleep up into two periods too, but it's not because of the lighting situation.