If you have not already done so, please read Blog Posts 1 through 5 that describe how sleep is important and beneficial. I will post specific information for parents and children based on my book, “Healthy Sleep Habits, Happy Child.” Please do not be put off by my book’s length. This is a reference book. Read only the topic of interest to you.
When I was much younger, I was a solo general paediatrician, always on-call. I became a sleep-deprived workaholic. Then, even a small sliver of light in the bedroom interfered with my ability to fall asleep for naps. It was so bad that I investigated installing cumbersome window boxes with opaque shades that old-time photo labs used to make a dark-room for developing film. I was hypersensitive to a little light because sleep-deprivation produces a state of higher neurological arousal.
This experience suggests that if your baby or young child is not sleeping well during the day, making the room pitch-black for naps might help your child nap better. I cared for one family that lived in a large city and they temporarily napped their baby in a large walk-in closet for light and noise protection (with the door open, of course). After the baby became better rested, he was able to nap well in his own room which was not pitch-black. So, if your child is not sleeping well, a very dark room for naps may be a temporary situation until your child becomes well-rested. However, among well-rested babies and young children there is a range of individual variation to light sensitivity. Some well-rested babies and young children appear to sleep well in rooms that are not very dark while others only sleep best in very dark rooms.
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