Everyone knows booking all your accommodation with the same hotel chain earns loyalty points, which can be traded for free stays and the occasional bottles of wine. Now a study shows that there could be performance benefits too.
People often experience trouble sleeping in a different bed in unfamiliar surroundings. This is a phenomenon known to psychologists as the “first-night” effect. This is because if a person stays in the same room the following night, he or she tends to sleep more soundly. Yuka Sasaki and her colleagues at Brown University in Providence, Rhode Island, set out to investigate the origins of this effect.
Dr. Sasaki knew the first-night effect probably has something to do with how humans evolved. The puzzle was in what way it can be beneficial. 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. This led her to wonder if people might be doing the same thing and feeling tired the next day as a result.
To take a closer look, the team studied 35 young and healthy people as they slept in the unfamiliar environment of the university’s Department of Psychological Sciences. The participants each slept in the department for two nights and were carefully monitored each time with neuroimaging techniques that looked at the activity of their brains. Their heart rates, muscle and eye movements were also recorded.
Dr. Sasaki found that, as expected, the participants slept worse on their first night in the lab 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. More specifically, on the first night only, the left brain did not sleep as deeply as the right brain did.
Wondering if the left brains indeed remained 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 of the same tone and irregular beeps of a different tone during the night. She worked out that, if the left brain stayed alert to keep guard in a strange environment, then it would react to the random beeps by waking people up and would ignore the regularly timed ones. This is precisely what she found.
Based upon these feelings, Dr. Sasaki argues in Current Biology that the first-night effect is a mechanism that has evolved to function as something of a neurological night watchman to wake people up when they hear noises when sleeping in an unfamiliar environment.
【小题1】What puzzled the researchers about the first-night effect?| A．What role it has played in evolution. | B．What benefit can be gained from it. |
| C．To what extent it can affect people. | D．The relationship between it and circumstances. |
| A．conducted studies on young and old people |
| B．got some idea from previous studies on birds and dolphins |
| C．found birds and dolphins had nearly the same sleeping patterns |
| D．found half of birds’ and dolphins’ brains remain awake while asleep |
| A．She analyzed the negative effects of irregular tones on brains. |
| B．She recorded the participants’ adaptation to changed environment. |
| C．She exposed the participants to two different kinds of noises. |
| D．She compared the responses of male and female participants. |
| A．They differed in their tolerance of irregular tones. |
| B．They tended to regard irregular beeps as a threat. |
| C．They felt sleepy when exposed to regular beeps. |
| D．They tended to enjoy certain tones more than others. |
