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Why do many of us find 61 difficult or impossible to fall asleep in a bed other than our own? Is it because the bed is 62 (comfort)? According to a new study published in Current Biology, a significant reason is 63 the scientists call “first night effect”. They believe that one side of the brain acts as a “night watch” to warn us about potential dangers. It forces us 64 (stay) awake on the first night in a new environment.
For the study, 35 young volunteers 65 (ask) to sleep in a sleep lab for several days. Meanwhile, researchers watched their brain activities.
According to the researchers, on their first night, the left brains were 66 (active) than the right brains and people had a hard time sleeping. However, left-brain activity decreased as days went by, 67 (fall) even to the point of complete calm. In this process, the participants got an increasingly better sleep experience.
The 68 (finding) suggest that the different rhythms of the sides of the brain affect our sleep. When the two sides work 69 (different), the balance between them is broken. Thus, the brain can’t relax and is sensitive to anything strange in the surroundings, just 70 it is in the daytime.
