Passage
One Questions 46 to 50 are based on the following passage9
That people often experience trouble sleeping in a different bed in unfamiliar surroundings Is
a phenomenon known as the "first-night"effect. If a person stays in the same room the following
light they tend to sleep more soundly, Yuka Sasaki and her colleagues at Brown University set out to
investigate the origins of this eftect
Dr Sasaki knew the first-night effect Probably has something to do with how humans evolved. The
puzzle was what benefit would be gained from it when performance might be affected the following da
She also knew from previous work conducted on birds and dolphins that these animals put half of their
brains to sleep at a time so that they can rest while remaining alert enough to avoid predators(H Ar t)
This led her to wonde
eople migh
the same thing. To
studied 35 healthy people as they slept in the unfamiliar environment of the university's Department of
sychological Sciences. The Participants each slept in the department for two nights and were carefully
monitored with
iniques that looked at the activity of their brains. Dr, Sasaki found, as expected, the
participants slept less well on their first night than they did on their second, taking more than twice
as long to fall asleep and sleeping less overall. During deep sleep, the participants brains behaved in a
similar manner seen in birds and dolphins. On the first night only, the left hemispheres (ik)of their
brains did not sleep nearly as deeply as their right hemispheres did
Curious if the left hemispheres were indeed remaining awake to process information detected in the
surrounding environment, Dr. Sasaki re-ran the experiment while presenting the sleeping participants
with a mix of regularly timed beeps (f a ) i)of the same tone and irregular beeps of a different tone
during the night. She worked out that, if the left hemisphere was staying alert to keep guard in a strange
environment, then it would react to the irregular beeps by stirring people from sleep and would ignore
the regularly timed ones. This is preci
sely
what she found
207年12月大学英语四级考況题く第一会)6
