阅读理解
If you have trouble falling asleep, listen up. You might fall asleep
15 minutes earlier and wake up far less during the night if you put on a pair
of socks at bedtime.
To understand why, you first need to grasp the relationship
between core body temperature and sleep. During daylight hours, the human body
has an average temperature of 37℃. But your core
body temperature drops as much as 1.2℃ over one night's
sleep. This gradual decrease is a key part of how we sleep. Put simply, the
faster you can lower your core body temperature, the faster you will fall
asleep.
One way that your body controls its temperature is through blood
vessels (血管)in the skin. If your body is too hot, your blood vessels widen,
pushing the warmer blood nearer the skin's surface, helping it to cool. If your
body is too cold, the opposite happens. Your blood vessels narrow, restricting
the flow of blood to the surface.
The palms of your feet are one of your body's most efficient heat
exchangers, since they are hairless and less protected than other skin
surfaces. Researchers have shown that warming the feet before going to sleep
using a warm foot bath or by wearing socks promotes blood vessel widening,
which in turn lowers the body's core temperature faster than going to sleep
with cold, bare feet.
Scientists suspect that socked feet have a sleep-benefiting effect
on the brain as well. The warm-sensitive neurons(神经元)in the brain
become more active when there's a temperature difference between the body's
core and the feet. Researchers have found that these neurons become more active
as we get sleepy and slow down as we wake up, so that warming up the feet
before bedtime may give them an extra drive, making you feel sleepier.
In a small study, researchers found that wearing a pair of special
"sleeping socks" not only sped up the coming of sleep, but increased
overall sleep time by an average of 30 minutes and cut nighttime waking
episodes in half. If you're worried about becoming too warm, look for socks
made of natural fibers.
(1)
In which section of a newspaper can we find this text?
A . Advertisement.
B . Lifestyle.
C . Opinion.
D . Trend.
(2)
What change does warm feet bring to the body?
A . Slowed brain reaction.
B . Narrowed blood vessels.
C . Reduced core body temperature.
D . Decreased blood pressure.
(3)
How might the brain's warm-sensitive neurons help sleep?
A . They might help to warm up the feet.
B . They might speed up temperature growth
C . They might slow down the brain's blood flow.
D . They might bring on sleepiness when activated.
(4)
What is the finding of the small study mentioned in the last paragraph?
A . The warmth of socks depends on their material.
B . People wearing socks fall asleep 50 percent faster.
C . Special socks increase temperature more effectively.
D . Sock wearing helps people sleep longer and wake less
答案: B
C
D
D