He says the solution is not to persuade teenagers to go to bed earlier. “The body’s natural rhythm is controlled by a particular kind of light,” says Kelley. “The eye contains cells that report to a part of the brain that controls our circadian rhythms over a 24-hour cycle. It’s like saying: ‘Why can’t you control your heartbeat?’”
Why does Kelley say that going to bed earlier is not the solution to waking up earlier?
Light, rather than the time people go to bed, controls people’s natural sleep rhythms It is difficult to convince teenagers to go to bed earlier It would interfere with the rhythm of activity of certain eye cells It would interfere with various social activities