File image:Elderly couple walking down corridor. Matt Rourke - AP
GETTING lost and losing your ability to navigate could be a red alert for dementia.

And changes in how we map our surroundings may provide an earlier sign of Alzheimer’s disease than memory loss, scientists have said.

Older people are worse at learning routes, spatial awareness and retracing their steps because of brain changes associated with ageing.

Healthy people can plot a route to a destination based on their current location.

But people at risk of dementia base the journey on landmarks, and often struggle to get from one landmark to the next as they can not learn the route in between.

Dr Thomas Wolbers, from the German Centre for Neurodegenerative Diseases, said: "It can take up to 10 years after the onset of Alzheimer’s for someone to show abnormal results on the standard tests. That’s 10 years you’ve lost for treating it."

The review, in the journal Neuron, suggests people should be tested for how their ability to find their way changes over time. - Daily Mail