Circadian rhythm sleep–wake disorders occur when your internal biological clock is out of sync with the external day–night cycle. Even if you have enough time to sleep, your body simply wants to sleep and wake at the “wrong” times.

Q: What is a circadian rhythm disorder?

It is a condition where the body’s internal clock is misaligned with normal social or environmental schedules.

Q: What controls the body’s internal clock?

A small region in the brain responds to light exposure and regulates hormones like melatonin.

Q: Can someone sleep normally but at unusual times?

Yes, some people sleep well but only very late at night or very early in the evening.

Q: What is delayed sleep phase disorder?

It is when a person naturally falls asleep very late (for example 2–4 AM) and struggles to wake early.

Q: What is advanced sleep phase disorder?

It is when someone becomes very sleepy early in the evening and wakes up extremely early in the morning.

Q: Is this just a bad habit?

No, in true circadian disorders the timing issue is biologically driven, not just behavioral.

Q: Can light affect circadian rhythm?

Yes, light exposure — especially blue light at night — can delay the body clock.

Q: How is it treated?

Treatment may include timed light therapy, strict sleep scheduling, melatonin at specific times, and behavioral adjustments.