Regarding sleep regulation, which statement aligns with the material?

Regarding sleep regulation, which statement aligns with the material?

• A. Low serotonin causes insomnia and melatonin is a precursor
• B. High serotonin causes insomnia and melatonin inhibits sleep
• C. serotonin has no effect on sleep
• D. Dopamine directly causes sleep

Answer: (A)

Sleep regulation hinges on serotonin providing the raw material to make melatonin, the hormone that signals the body to sleep. Serotonin is converted into melatonin in the pineal gland, especially as darkness falls. When serotonin availability is low, melatonin production can drop, making it harder to fall asleep or stay asleep, which aligns with insomnia. Melatonin’s role is to promote sleep onset and maintenance, so the idea that reduced serotonin leads to less melatonin and poorer sleep fits the material. The other ideas miss the relationships: serotonin does affect sleep, and melatonin does not inhibit sleep; dopamine is more associated with wakefulness than with directly causing sleep.

Sleep regulation hinges on serotonin providing the raw material to make melatonin, the hormone that signals the body to sleep. Serotonin is converted into melatonin in the pineal gland, especially as darkness falls. When serotonin availability is low, melatonin production can drop, making it harder to fall asleep or stay asleep, which aligns with insomnia. Melatonin’s role is to promote sleep onset and maintenance, so the idea that reduced serotonin leads to less melatonin and poorer sleep fits the material. The other ideas miss the relationships: serotonin does affect sleep, and melatonin does not inhibit sleep; dopamine is more associated with wakefulness than with directly causing sleep.