Marshall has been diagnosed with non-24-hour type circadian rhythm sleep-wake disorder.Which of the following is a likely symptom of Marshall's disorder?

A) He sleeps in three periods within 24 hours.
B) He experiences a free-running sleep-wake cycle that is not calibrated with the light-dark cycle of the day.
C) He falls asleep suddenly in the middle of the day.
D) He often cannot sleep for up to 48 hours.

Non-24-Hour Type

A circadian rhythm disorder leading to a sleep-wake pattern that extends beyond the typical 24-hour cycle, affecting sleep regularity.

Circadian Rhythm Disorder

Disruptions in the natural, internal process that regulates the sleep-wake cycle over a 24-hour period.

Free-Running Sleep-Wake Cycle

A sleep pattern that occurs without the cues of natural light-dark cycles, often seen in blind individuals or in conditions of isolation from standard time cues.