Forbes: A study showed that for every extra hour of TV children watched, they tended to sleep seven minutes less per night (on average).
There are a couple of possibilities as to why the TV-poor sleep connection exists. The first is that TV can be stimulating enough that it could “phase shift” (delay by a sleep cycle) the onset of sleep. Watching violent TV might also lead to interrupted sleep, since it might create worry or anxiety that could prevent a kid from getting back to sleep if awakened in the middle of the night.
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