8．For most people today，their GPS （Global Positioning System） has become a lifeline，giving directions to the nearest bathroom or restaurant．But the（51）A we pay for the convenience could be our sense of（52）B．
"I do think GPS devices cause our navigational skills to atrophy （萎縮），"said Nora Newcombe，a psychologist at Temple University in the US who studies how the human brain（53）D．"The problem is that you don't see an overview （概貌） of the area and where you are in relation to other things．"
To understand the risk，you first need to （54）C how our brain keeps us from getting lost．Through experiments，researchers have found that our navigational strategies usually fall into two groups．
The first involves a spatial （空間的） map inside your brain．As you（55）A an area，you think about how the streets fit together and the best way to get between different locations．（56）B，the map lets you navigate between any two points in the area．
The second involves a series of landmarks and steps：Turn right at the gas station，and your school is on the left．It's quick and reliable，（57）C less flexible-it doesn't help you get from your school to a totally new place，even if it's nearby．
These two methods might not sound all that different，but according to Newcombe's research，people who are bad at navigation have trouble with the first strategy-creating spatial maps．（58）D，through further studies Newcombe has come to believe that people's ability to create spatial maps is decided by how（59）A we use the skill．
That helps（60）C what happens when people trust themselves with GPS devices．According to Veronique Bohbot of McGill University，people using navigation based on direction show more activity in their caudate nucleus （尾狀核）-the part of the brain that is good at following directions-but less activity in the hippocampus （海馬體），which creates the spatial maps．
It turns out that our sense of direction isn't the only thing we could lose．
One thing that could go is our（61）B to the environment we travel through．Researchers have found that when people（62）A GPS directions while driving，their memory of their trip is of a route on a（63）D，rather than the landscape they traveled through．
（64）C，researchers believe that active navigation（65）B the type of thinking used in all kinds of spatial processes．"It's things like urban planning，and looking at a map to see where resources are．That's not replaceable by your phone，"Newcombe said．
| 51．A．price | B．service | C．a(chǎn)ttention | D．curiosity |
| 52．A．balance | B．direction | C．control | D．satisfaction |
| 53．A．works | B．thinks | C．learns | D．navigates |
| 54．A．decide | B．calculate | C．understand | D．predict |
| 55．A．explore | B．cover | C．travel | D．map |
| 56．A．Unfortunately | B．Eventually | C．Slowly | D．Reluctantly |
| 57．A．even | B．a(chǎn)lthough | C．but | D．much |
| 58．A．For example | B．As a result | C．In fact | D．What's more |
| 59．A．often | B．much | C．long | D．soon |
| 60．A．move | B．evaluate | C．explain | D．detect |
| 61．A．judgment | B．connection | C．decision | D．treatment |
| 62．A．rely on | B．focus on | C．object to | D．a(chǎn)dapt to |
| 63．A．window | B．key | C．press | D．screen |
| 64．A．However | B．Therefore | C．Moreover | D．Above all |
| 65．A．displays | B．improves | C．provides | D．involves． |
