After you have a long day at school or work, getting a bit of shut-eye on the way home is sometimes just what the doctor ordered. But sleeping too long and ending up way past your destination is a real possibility. According to research from sleep specialists in the US, there are several possible explanations for being able to nap during a train or bus ride and still get off at the right stop.
One theory states that some people have established sleep pattern that allow them to sleep and wake up at precisely the same time each day. That means their body knows when to wake up and get off the train. Another theory is that people are more likely to recognize the name of their stop, so their brain wakes them up when they hear it announced. Alternatively, those who can effectively sleep on the train might actually be waking up at every stop, but not long enough to become conscious until they know they've reached the right place.
These short naps might work for those who are really exhausted, for even a brief rest has the benefit of reducing stress and helping you relax a little. But if you are travelling really far each day, chances are that you will reach rapid eye movement (REM) sleep cycles. According to Dr. Marc Leavey, who has studied this skill, "You're more likely to be tired or disoriented when you wake up from these dreams, so if you're sleeping for longer than 20 minutes, you may find it harder to wake up out of this dream state. If you're in a deep REM sleep, you're more likely to miss your stop or sleep through it.” Not everyone can do it, but some people can run their sleep cycle like clockwork and take a nap on public transportation.
【答案】Sleep experts are trying to explain why people can nap without missing the stop. Besides fixed sleep pattern and the ability to recognize station names, people don’t become fully awake before they reach the destination. While naps relieve stress and are relaxing, experts warn of possibility of missing the stop if the nap is longer than 20 minutes.