If a patient consistently wakes up early and cannot fall back asleep, disrupting sleep cycles, which mechanism related to hormone regulation is most likely dysfunctional?

💡 Explanation

Dysfunctional melatonin secretion timing disrupts the body's circadian rhythm, which regulates sleep-wake cycles, because melatonin levels influence the timing of sleep onset and offset. Therefore, the patient wakes up early and cannot fall back asleep, rather than leptin, cortisol, or ghrelin influencing the specific sleep timing.

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