New research reveals that walking requires more thought than you might think, and cognitive decline -- at least in the elderly -- can make the travel that much harder.

The findings suggest that doctors should be aware of the cognition-walking link and keep an eye out for patients who can't think clearly, said study co-author Roee Holtzer, an assistant professor of psychology and neurology at Albert Einstein College of Medicine in New York.

"We need to be cognizant of the fact that they may walk less efficiently and may be at higher risk for falls," he said.

Walking is, of course, a routine part of everyday life.

"It's very much equivalent to independence and one's ability to get around and function alone without assistance," Holtzer said.

But older people, in particular, are prone to unsteady gaits and falls -- the leading unintended injury among elderly people, said Denys T. Lau, an assistant professor of medicine at Northwestern University who studies aging. Among other things, falls can cause hip fractures and lead to long-term residential care, hospitalization and even death.

In order to measure how the brain affects walking, Holtzer and colleagues gave cognition tests to 186 people aged 70 and older. They then watched them as they walked through a corridor on a specially designed mat.

The findings appear in the March issue of the journal Neuropsychology.

Holtzer's team found that the fastest walkers had higher scores on certain cognitive tests, including those that measure memory and planning abilities. Higher levels of verbal ability were also linked to faster walking, except when the seniors had to walk and recite alternate letters of the alphabet at the same time.

Why is thinking so closely linked to walking ability? "There's a lot going into gait. You have to move your legs, maintain your balance. And when you walk outside you have to be able to really see where you're walking so you don't bump into things," Holtzer said. "It can be a very complex task."

The findings have important implications, he added. First, they help point out how cognitive rehabilitation -- including the improvement of your ability to pay attention -- could help boost walking skills and prevent falls.

Lau, who's familiar with the study, added that this research suggests new ways to design diagnostic tests that can help spot seniors at risk of falling.