Which sleep-wake pattern involves going to bed and waking earlier than the desired times?

• A. Advanced sleep phase type
• B. Delayed sleep phase type
• C. Circadian rhythm disorder
• D. Sleep deprivation

Answer: (A)

A shift of the circadian phase earlier leads to feeling sleepy and going to bed early, with waking quite early in the morning. This pattern is called the advanced sleep phase type. It means the internal clock is ahead of society’s usual schedule, so you chronically sleep and wake earlier than you’d like. This contrasts with a delayed sleep phase type, where sleep and wake times are pushed later, making it hard to wake in the morning. Circadian rhythm disorder is a broader category that includes such patterns, but the description given fits the advanced sleep phase type specifically. Sleep deprivation, by contrast, is about not getting enough total sleep, not about an earlier-than-desired timing.