So Why Do We Walk In Circles When Lost In The Forest?

By James Donahue

There is an old story, only recently proven by scientific research, that people who get lost in the forest walk in circles, often crossing their own paths, when they believe they are moving in a straight line.

It has happened to many ardent hunters and a number of people who simply get disoriented while strolling in a forest. My wife’s brother, Wayne, became lost while deer hunting in a forested area not far from his home and did not find his way out until he spent a night in the woods. Wayne knew the stories and chose to sit down in a sheltered area and wait for the sun to guide him once it rose in the east.

I recall my own adventures in large wooded areas near my home in Michigan and cannot recall ever being so lost I could not find a way to a way back to a stream, road or pathway that brought me to civilization. I do recall surprise at where I emerged from the forest . . . sometimes far from where I thought I would be.

So why do we lose all sense of direction when in a forest . . . or for that matter, in any area where everything looks the same? Examples would be on a raft at sea, a large mall parking lot, or in the middle of a desert.

Researchers at the Max Planck Institute for Biological Cybernetics in Germany recently examined this phenomenon and reported their findings in a recent issue of Current Biology.

The team attached GPS locators to volunteers and then sent them walking for several hours in the Sahara desert in Tunisia and the Bienwald forest, Germany. They found that the walkers could maintain a straight line when they could orient themselves with the sun or moon. Sailors who are trained in navigation also use the stars. But when the sky was clouded and these markers were removed, the walkers always walked in circles. Sometimes they veered left and sometimes right, but always in circles.

When subjects were blindfolded in additional testing, they moved in extremely tight circles, sometimes moving in an area no larger than a normal basketball court.

The question is, why does this happen?

One old explanation was that one leg is longer or stronger than the other, making the walker tend to swing in one direction or the other when they believe they are following a straight line.

Dr. Jan L. Souman, who was involved in the research and studies multisensory perception, noted that when normal visual guides like the sun or moon are removed, the brain “appears to be lacking a fundamental visual cue to help make sense of the jumble of other data it is receiving.

“The brain has different sources of information for almost everything,” Souman said. He explained that there is a complicated interplay of  “images flowing over the retina, the sense of acceleration or turning in the inner ear, even how the muscles and bones are moving that are combined in the brain to give a sense of where the body is going.” He said that to make sense of it all, however, a person needs certain types of “absolute cues” to help establish directions.

Ed Young, a British blogger whose columns in a page marked “Not Exactly Rocket Science,” tackled the problem of circle walking.

Young noted that the Max Planck study also studied a group of 15 blindfolded people loose in a large field with instructions to walk straight ahead. “All of them walked in very random paths, including large flamboyant loops, and, on occasion, surprisingly small circles of as little as 20 meters in diameter. Only three of the 15 people consistently veered in one direction and they did indeed go rounds in circles. The others walked more chaotic paths.”

Young said the rest meandered in various directions. One volunteer who participated in both the field and forest experiment, veered in opposite directions. This, Young wrote, “strongly argues against the influence of asymmetric legs or brains. . . Without landmarks to guide them the walkers were relying on feedback from their bodies and their sense of balance. These cues can help over short distances, but Souman says that they soon build up ‘sensory noise’ that renders them inaccurate and causes the person’s trajectory to drift.”

All of the walkers in the field were allowed to walk for 50 minutes, yet none of them got more than 100 meters from where they began.

Souman concluded: "Ironically, in the age of ubiquitous navigation systems in airplanes, cars, and even mobile phones, we are only beginning to understand how humans navigate through their environment, exploring uncharted terrain."

Young added that the study shows that even the simple act of walking in a straight line is more complex than it might first appear.