Seniors Haven't Adjusted to Declining Sight

Older adults often fail to compensate for diminished eyesight

(RxWiki News) With age, it's not uncommon to experience increased falls. But many also experience a decline in sight and tend to have difficulty in compensating for their impairment.

In adults over the age of 65 who are most susceptible to falls, their ability to collect visual information to help coordinate movements is compromised and they are unable to adequately compensate for this problem.

"Walk more cautiously as your vision declines."

Fiona N. Newell and Annalisa Setti, researchers from Trinity College Dublin in Ireland, found that older adults who were not prone to falling could compensate for failing sight, unlike those prone to falling who failed to slow and proceed more cautiously through a walking course.

Researchers asked 11 participants over the age of 65 to walk a course that consisted of an invisible triangle. One side of the triangle had sensors that recorded the gait of participants. Of the participants, five were considered prone to falling and had fallen at least once in the prior 12 months. An additional six participants with an average age of 33 were used as a control group.

After testing the ability of participants to navigate the unmarked course, they were asked to walk it again wearing safety goggles wrapped with masking tape that blurred their vision but still allowed light in.

Each group had difficulty when their vision was blurred, but especially the group that was prone to falling. When the vision of the other two groups was blurred, participants walked more slowly to compensate.

The fall-prone group, however, did not reduce their walking speed. They also made more errors in returning to the starting point of the course.

It was known that older adults tended to use spatial memory to guide movement less than younger individuals. This study noted a similar dilemma, with the fall-prone older adults relying too heavily on visual information for spatial cognition without compensating for the lack of visual information.

Newell and Setti wrote that the study suggested that spatial cognition is more greatly compromised among fall-prone older adults, concluding that visuo spatial information seems to play a key role in orchestrating this integration process and renders those prone to falling particularly dependent on visual input for precise spatial awareness.

They indicated that future research on spatial abilities in individuals with visual impairment, particularly age-related visual loss over a long term, would provide further insight into the role of vision.

Dr. Christopher Quinn, an optometrist with Omni Eye Services said a decline in sight without the ability to compensate for it is common in older patients.

"One of the most common reasons for a decline in vision is the result of cataracts," he said. "Cataracts can degrade visual performance in many ways even if visual acuity (what you can read on an eye chart) is not severely diminished. Fortunately, modern cataract surgery can help restore visual function and improve the quality of life for those seniors affected."

The research was published in journal Insight: Research and Practice in Visual Impairment and Blindness.

Review Date: 
September 6, 2011