Some people are like homing pigeons; Drop them off anywhere. and they’ll find their way around. Other people. through, can’t tell holding a map upside down. Are the directionally challenged just bad learners?
Not all of your navigational(导航的)skills are learned. Research shows that your sense of direction is innate. An innate ability is something you are born with. Your brain has special navigational neurons--head-direction cells, place cells, and grid cells(网格细胞)--and they help program your inside compass when you’re just a baby.
In 2010. scientists carried out an experiment to study baby rates’ activity in their brains. Although the rats were newborns. the researchers discovered that their head-direction cells(which help them recognize the direction they’re facing) were fully grown and developed. The rats. it seemed. were born with a sense of direction. And they hadn’t even opened their eyes yet!
Humans. of course, are not rats. But the hippocampus --the brain we use for navigation--is similar in most mammals. If the rat’s compass develops this way. then it’s likely a human’s compass does, too.
If we’re born with a sense of direction. then why are some people so good at getting lost? The scientists found that the two other cells---place and grid cells--developed within the first month. Place cells are thought to help us form a map in our mind. while gird cells help us navigate new and unfamiliar places. The two cells work together, and that’s where the trouble might be.
People who took part in a 2013 study played a video game that required them to travel quickly between different places. Monitoring their brains. the scientists. According to researcher Michael Kahana, differences in how gird cells work may help explain why some people have a better sense of direction than others.
32. What did the 2010 research find?
A. Rats have a natural ability to recognize directions
B. Rats’ hipppcampus is different from that of humans
C. Rats usually find their way without opening their eyes
D. Baby rats have as many head-direction cells as grown-ups
33. What do we know about our navigational neurons?
A. Place cells let us know how to read a map
B. Grid cells help us reach the place we are going to
C. They help us use a compass when we lose our way
D. Place and grid cells grow later than head-direction cells
34. Why are some people so good at getting lost?
A. They can’t remember landmarks
B. Their grid cells can’t work very well
C. They are unfamiliar with new places
D. Their ability to follow directions is poor
35. What is the text mainly about?
A. Human navigational skills B. The compass in rats’ body
C. Why grid cells are useful D. How homing pigeons work
ADBA
A. Profits enlarging B. Technology developing C. Education investing D. Benefits transferring E. Dominance disappearing F. A nation rising |
The following is an imaginary diary entry written by US president. This diary is part of Global Trends 2025, which was written by the US National Intelligence Council
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Global wealth and economic power will shift from West to East.
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The transition from old fuels to new will be slow, as will the development of new technologies that present feasible alternatives to fossil fuels or help eliminate food and water problems. All current technologies are inadequate, and new ones will probably not be commercially possible by 2025