By Brian Alexander
We all get lost, but how many times have you been unable to locate the bathroom — in your own house?
Researchers at the University of British Columbia recently reported the first case of a woman who, without any apparent brain damage or lesions or other mental impairments, is unable to find her way around any environment. The researchers believe there may be many others affected by this newly discovered developmental disorder.
The 43-year-old woman has been unable to navigate the world by herself since she was 6 years old. Since her case was first reported last month, about 60 other people who believe they have the same condition have contacted the researchers, says neurologist Giuseppe Iaria of UBC.
This isn't a matter of losing your car in the mall parking lot, walking five blocks in the wrong direction after emerging from a subway, or common absent-mindedness like Einstein, who was famous for having a poor sense of direction. These navigationally-challenged people have a developmental disorder that prevents their brains from forming a map of their environment, says Iaria. "They have been unable to orient since they were children," says Iaria. "They never developed this cognitive ability."
Most of us, Iaria explains, can create mental maps of our surroundings by the time we are about eight or nine. It is one of the last cognitive abilities we learn, he says, because it is so complicated, involving an entire system of cross-referencing in our brains. "It requires attention, memory, perception," he explains.
Whether in new or familiar locations, we observe landmarks, distances, directions and then use these cues to construct a cognitive map in our heads. Women tend to use physical landmarks such as a building, while men rely on distance, experts say. So when a woman gives directions, she's more likely to say 'look for the theater, the turn right and walk until you see the bank,' according to scientists. A man typically would tell someone to "go straight for 100 meters, turn left, there you are.'
Mostly this variation depends on personal preference and the structure of the brain's hippocampus, which varies from person to person, Iaria explains. The ability to navigate also requires a connection between the hippocampus and other parts of the brain, too. For a few people, there seems to be a short-circuit in the network.
When researchers compared functional magnetic resonance images of study participants with the first woman, they found that normal hippocampus activity signaling cognitive map use was virtually absent in the woman, compared to others.
The woman was asked to learn a simple computer-based environment featuring four landmarks. It took her six days, but when new fMRI images were taken, they saw changes, an indication that her hippocampus isn't broken. Apparently some neural snafu is preventing communication with other regions of the brain when it comes to this one ability.
No other triggers or malformations have been found. In fact, the woman seems completely normal in every other way, says Iaria. It is as if she didn't pick up one item in the cafeteria line to create a full tray of cognition.
Most people with the disorder in the study seem to have experienced it since childhood. Half of the people who have contacted Iaria say they get lost in their own house. They had few friends growing up because they rarely went anywhere. Driving is difficult, although GPS devices have helped many, Iaria says.
According to Iaria, a Denver woman with the condition has developed a coping strategy for when surroundings begin to seem alien. She stops, closes her eyes, spins around three or four times and then opens her eyes until things start to look familiar again. She has to repeat this every few minutes.
There are no estimates on how many people may be affected and there are still far more questions than answers about the condition. Meanwhile, researchers are trying to develop an assessment test for children who they hope could be helped with early therapy.