We all know people who say they have “no sense of direction,” and our tendency is almost always to minimize such claims rather than take them at full force.

Yet for some people that description is literally true, and true in all circumstances: If they take a single wrong turn on an established route they often become totally lost. This happens even when they are just a few miles from where they live.

Ellen Rose had been a patient of mine for years before I realized that she had this life-long learning disability.

I was made aware of it not long after I moved my psychology office from Agawam, Massachusetts to Suffield, Connecticut, just five miles away.

I gave Ellen a fresh set of directions from the Springfield, Massachusetts area that took her south on Interstate 91 to Exit 47W, then across the Connecticut River to Rte 159 in Suffield. I thought it would pose no problem at all for her.

A few minutes past her scheduled appointment time she called to say that she was lost. She had come south on Route 91 and had taken the correct exit, but she got confused and almost immediately hooked a right onto a road going directly north, bringing her back over the Massachusetts line to the town of Longmeadow.

She knew this was wrong but did not know how to correct it, so I repeated the directions to get on 91 South and so on.

Minutes passed, and then more minutes passed, and she called again to say that somehow she had driven by the exit she was supposed to take and was in Windsor, Connecticut. I kept her on the phone and guided her turn by turn to my office.

When I asked her why she hadn’t taken Exit 47W, she said that she saw it but it came up sooner than she expected so she kept going.

This condition—developmental topographic disorientation—didn’t even have a formal name until 2009, when Giuseppe Iaria reported his first case in the journal Neuropsychologia.

To understand DTD it is best to begin by saying that there are two main ways that successful travelers use to navigate their environment.

The first is to follow a prescribed route from here to there. Cognitive psychologist Barbara Tversky describes route navigation as a series of paths and choice points that is basically egocentric: it is constructed for the purpose of reaching one particular goal from a fixed starting point, and the entire journey is explained from the point of view of the traveler.

Start here. Go straight for one mile and take a right onto Elm Street. When the road splits, go toward the flagpole and follow that road over the bridge. Go to the first traffic circle and take the second exit. The restaurant is 2 miles down the road on the left.

The second navigational strategy involves a bird’s-eye view—a map—of the general area.

Maps are overviews, “surveys of a space of possibilities,” that lay out a variety of possible paths. Maps almost always rely on cardinal directions, usually east-west and north-south, that anchor them to a larger space.

When we use a map to get somewhere, it is up to us to figure out the best route, or the array of alternatives, for ourselves.

So how does this work out in the real world?

In her 2019 book, Mind in Motion, Tversky acknowledges that most of us do not carry a file drawer of maps in our heads.

Instead, we use a combination of methods to get where we are going: part turn-by-turn directions, part bird’s-eye view, and part general map-like information (it’s somewhere near the center of town; we’ll be traveling toward Omaha; the mid-day sun is on our left, so we are still heading west) and helpful landmarks.

For this reason, Tversky refers to our wayfinding plans not as “cognitive maps” but as “cognitive collages,” and her research demonstrates that when we spontaneously impart directions to another person we almost always use a stitched-together description.

But it is important to note that most navigational directions of moderate complexity depend in part on the ability to understand a map perspective.

Sometimes maps just make for better directions, but they are essential if we make a mistake and have to figure out how to correct our course.

The problem for Ellen is that she is not able to create a bird’s-eye view on her own and, likewise, can’t really make good use of one when it is provided by others.

Like other people with DTD, she can follow a route in pieces, but it never becomes part of a larger spatial understanding. That’s because she does not have a larger spatial understanding of her environment.

A couple of years ago, for example, Ellen was driving in the town of West Springfield and unintentionally wound up crossing the Connecticut River into Springfield. She landed on Carew Street, only one mile from the hospital where she worked and two-and-a-half miles from Winchester Square, where she grew up.

Lacking even a sketchy map perspective of that part of town, she could not establish her bearings and did not know where to turn. So she drove around randomly, as if she was a stranger in a strange place. Fortunately, she eventually spotted a landmark close to the bridge that crossed the river back into West Springfield.

This experience was not a fluke. When I asked Ellen to indicate the relative positions of Holyoke, Granby and Belchertown on a blank sheet of paper, her rendition was totally wrong. This in spite of the fact that the towns line up one after the other on a 13-mile stretch of U.S. Route 202, which is well known to her.

I asked her to draw a diagram of the second floor of the house she shares with her daughter and son-in-law. It was a difficult task for her (she lives on the first floor but is very familiar with the second.)

She described her effort not as a bird looking down from above, but as a spider crawling across the paper tracing a route from one room to the next.

Like dyslexics who learn how to adapt to a world of street signs, restaurant menus, and official forms, people with DTD learn how to navigate in their environment without having a mental blueprint of where they are going.

For twenty years Ellen was able to function successfully as a school bus driver by relying solely on a route strategy. She carried detailed notes with her every day, consulted them religiously, and added little mnemonics to keep herself on track.

Ellen has always wondered what was wrong with her. She knew that when others ascribed her problems to simply not paying attention they were mistaken. She worried that her problems traveling might be a sign of something more ominous than just getting lost easily, but had no idea what that might be.

Finding out that she had developmental topographic disorientation was a relief. Knowing that something has a name can be a liberating experience. All of a sudden it is a thing, a concept with defining characteristics and boundaries. It is, in a way, a kind of map.