March 3, 2010 at 5:58 PM ET
Kavita Varma-White writes:
When it comes to navigation skills, some of us are homing pigeons. Others are mice in a maze.
The sharp navigators are those who can figure out which way they need to go in an unfamiliar setting to get to their destination. No GPS needed to find their way around town. No always stopping for directions. Some folks, meanwhile, are hopelessly disoriented — the type that gets lost in a paper bag.
A new study suggests that skillful navigation just may be in your genes.
Say you are in a city — Washington D.C., for example — and you emerge from a Metro station to walk to a specific destination. For a minute you feel discombobulated. But, glancing around, you see the Capitol building, and a layout of surrounding streets helps you pinpoint your location. What if the landmark and roads didn't help?
Previous scientific research suggests that humans, rats, chicks, chimps and even fish use geometry to reorient themselves in space. They mentally visualize the geometry of their surroundings — corners and walls — to figure out where they are. But the new study indicates that genes may play a part in that ability.
The new study, conducted by lead author Laura Lakusta, an assistant professor of psychology at Montclair State University, Barbara Landau, the Dick and Lydia Todd Professor of Cognitive Science at the Johns Hopkins University, and Banchiamlack Dessalegn, a postdoctoral fellow at the University of Chicago, compared the navigation skills of normally developed adults and children with people who have Williams syndrome.
"We found that people who suffer from the genetic disorder Williams syndrome have trouble reorienting themselves, a basic process that is shared among human children and adults, and a variety of non-human species," Lakusta said. "Our finding that individuals with Williams syndrome show this kind of impairment suggests an important link between genes and the system that is used for reorientation."
Williams syndrome, a rare condition which occurs in one in 7,500 people, is caused when a small amount of genetic material is missing from one human chromosome. Individuals with Williams syndrome have strong language skills and are extremely social, but they have trouble with tasks like doing puzzles or copying patterns or navigating their bodies through the physical world.
In the study, Lakusta and her team challenged individuals with Williams syndrome to find a hidden toy in a rectangular room. The room had two long walls and two short walls and was covered in black felt. The Williams syndrome individuals were shown the toy and where it was hidden in one corner of a room. They were asked to close their eyes and were rotated for a few seconds. Then they were asked to find the toy.
When looking for the object, the Williams syndrome individuals — who were both male and female ranging from age 9 to 27, "searched all the corners randomly," Lakusta said, as if they had never before seen the overall geometry of the room or the lengths of the walls and their geometric relation to each other.
When testing a group of college students and a group of 3- and 4-year-olds who did not have Williams syndrome, Lakusta and her team found a more typical pattern of responding.
"If we hid the toy left of the short wall and right of the long wall, they could mentally construct an image of the room and find it, even if they became disoriented. They would tend to search the geometrically appropriate corner. They could figure out that there are two corners where the toy could be. This is the geometric pattern of responding," Lakusta said.
"The Williams syndrome subjects could not construct a mental map of the geometry of the environment," she said.
The study was recently published in the online Early Edition of the Proceedings of the National Academy of Sciences.
While other research studies have suggested a link that certain brain areas might be responsible for the behavior of reorienting, there has been no evidence that it might be linked to a specific gene, Lakusta said. "Now we know that, in general, genes can be deleted and we could see this impairment of orientation."
For those who are navigationally-impaired, this kind of research is a small but important step in understanding why you may have a hard time getting where you need to be.