Why Mom Wakes Before Dad | Sleep, Seasonal Depression & Sex
Differences betweenِ males andِ females abound, ofِ courseِ — butِ some areِ found inِ the oddest places.
New research hasِ foundِ that women tend toِ haveِ shorter, earlier sleep cycles thenِ men.
This makesِ women typically goِ to bed earlier andِ get upِ earlier inِ the morning.
They studied twoِ indicators ofِ circadian rhythm, theِ patient’s core body temperature andِ levels ofِ the hormone melatonin — thought toِ play a role inِ setting sleep-wake cycles — whileِ theِ patients followedِ extreme schedules (following a sleep-activity cycle spread across a 20 orِ 28 hour day, insteadِ of theِ normal 24) inِ a dimly lit room.
This environment allows theِ researchers toِ measure theِ natural circadian rhythms ofِ the individuals, whichِ areِ normally reset daily byِ exposure toِ natural light.
Without outsideِ cues, theِ body reverts toِ itsِ natural cycle, whichِ isِ sometimes longer orِ shorter thanِ 24 hours.
The finding couldِ have toِ doِ with differences inِ estrogen levels, theِ researchers say.
This couldِ mean thatِ hormone levels couldِ change circadian rhythm, thoughِ thisِ evidence onِ pre- andِ post-menopausal women suggests theِ sleep cycles areِ related toِ hormone exposure duringِ development, notِ adult levels.
Figuring outِ what controls ourِ biological clocks isِ one ofِ the mostِ important questions inِ human chronology research rightِ now, Alfred Lewy, ofِ the Oregon Health andِ Science University inِ Portland, told LiveScience.