Brain's 'homing signal' helps us navigate

Scientists have discovered where our 'sense of direction' comes from in the brain, a finding that explains why some people are better navigators.
It has long been known that some people are better at navigating than others, but until now it has been unclear why.
The latest study by University College London researchers showed that the strength and reliability of 'homing signals' in the human brain vary among people and can predict navigational ability.
In order to successfully navigate to a destination, you need to know which direction you are currently facing and which direction to travel in, researchers said.

The latest research shows that the part of the brain that signals which direction you are facing, called the entorhinal region, is also used to signal the direction in which you need to travel to reach your destination.
This part of the brain tells you not only which direction you are currently facing, but also which direction you should be facing in the future.

In other words, the researchers have found where our 'sense of direction' comes from in the brain and worked out a way to measure it using functional magnetic resonance imaging (fMRI).
"This type of 'homing signal' has been thought to exist for many years, but until now it has remained purely speculation," said Dr Hugo Spiers, who led the study.

"Studies on London cab drivers have shown that the first thing they do when they work out a route is calculate which direction they need to head in.
"We now know that the entorhinal cortex is responsible for such calculations and the quality of signals from this region seem to determine how good someone's navigational skills will be," Spiers said.
In the study, 16 healthy volunteers were asked to navigate a simple square environment simulated on a computer. Each wall had a picture of a different landscape, and each corner contained a different object.
Participants were placed in a corner of the environment, facing a certain direction and asked how to navigate to an object in another corner.

"In this simple test, we were looking to see which areas of the brain were active when participants were considering different directions," said Spiers.
"We were surprised to see that the strength and consistency of brain signals from the entorhinal region noticeably influenced people's performance in such a basic task.
"We now need to investigate the effect in more complex navigational tasks, but I would expect the differences in entorhinal activity to have a larger impact on more complex tasks," Spiers said.
The entorhinal region is one of the first parts of the brain affected by Alzheimer's disease, so the findings may also help to explain why people start to get lost in the early stages of the disease.