'Where am I?' Internal GPS breaks down in old age
Scientists say they have solved the mystery of why elderly people sometimes get lost.
Researchers have found that 'GPS cells' in the brain, which keep track of direction of travel, deteriorate with age and start acting more erratically.
Everyone has as group of special cells in the brain which act like a grid on a map, firing to the left or right, front or back, depending on a person's movement, and creating an internal map.
Scientists at the German Centre for Neurodegenerative Disease (DZNE) believe that map essentially fades with age, but think it may be possible to find drugs to boost the activity of these grid cells.
"When you move around an unfamiliar environment, it is perfectly normal to get lost, yet, this tends to happen more often to older people," said Matthias Stangl, a researcher at the DZNE.
"We had the hypothesis that so-called grid cells might be implicated. A major part of the navigational processing is done by these cells. They are specialised neurons located in the brain's entorhinal cortex. Therefore, we guessed that deficits in grid cell function might be a cause for problems in navigation."
The scientists asked 41 healthy young and older adults to perform navigation tasks while scanning their brains. They found older people did less well, and the scans showed their grid cells were less active.
The researchers also believe the findings may open up new ways to detect Alzheimer's disease. The cells are near the hippocampus, which is one of the first areas to be damaged by the plaques which cause Alzheimer's. (© Daily Telegraph, London)