“A new Northwestern University study is the first to show that something may be happening cognitively that leads people to gradually become more biased, and at the same time more accurate, when it comes to their spatial memory as they become more familiar with a particular area.
In other words, as people better understand the relationship between buildings on a campus, for example, over time memory biases cause them to exaggerate the distance between the north and south ends of campus. They become more and more biased and see the boundaries of campus as being much farther apart.
[…]
There have been other studies demonstrating the existence of spatial biases and how they affect spatial judgments, but Uttal said there were never studies about how such biases developed and how they were learned.
[…]
First, Uttal said, “We can get simultaneously more accurate and more biased at the same time, which seems counterintuitive, but it really shows how different kinds of information are stored and thought about differently in the mind.”
http://www.northwestern.edu/newscenter/stories/2011/01/spatial-memory.html