FRIDAY, Aug. 31, 2001 (HealthDayNews) -- A test that measures what the brain does with what it sees may be better than a standard eye test at predicting which senior citizens may be dangerous drivers.
The exam, called the useful field of view (UFOV) test, gauges how fast the brain processes visual information. Its co-inventor calls it a more accurate forecaster of risk factors in older drivers.
State agencies are beginning to show interest. The UFOV is now being field-tested in Florida, and it is also the subject of a large study in Maryland.
"Most older adults, over the age of 65, are indeed safe drivers," says co-inventor Daniel Roenker, a professor of psychology at Western Kentucky University in Bowling Green. "The image the American public has is that there are all those old people out there who are nothing but a menace on the road. That's the image; that's not the reality."
Roenker and another co-inventor, Karlene Ball, a professor of psychology at the University of Alabama in Birmingham, presented their findings this week at a meeting of the American Psychological Association in San Francisco.
"The trick for motor vehicle departments is finding the [senior citizens] who may not be safe, before something tragic happens," Roenker says.
"The regular test used by motor vehicle departments around the country measures visual acuity, which is your ability to see detail. We all know it as a standard eye chart," Roenker says.
The UFOV, 17 years in development, puts senior citizens through three tests, each one progressively more difficult.
The first test presents an object, about one inch across, on a screen. It is flashed at progressively faster display speeds until it can no longer be identified, Roenker says.
"We are not interested in measuring reaction time," he notes. "What we are manipulating is how long an image is physically available to someone."
If a person's mental processing system is slow, then an image needs to be available longer, he says.
"Most older adults can perform [the] test rather easily, at display durations as brief as 1/60th of a second. That's a tenth of an eye blink," Roenker says. "But longer exposure duration means that a person's visual processing has slowed down."
The next two tests build upon the first.
"We flash a second object somewhere else on the screen as they're trying to identify the first," Roenker says. "The job is to identify the center of the screen and then locate a new peripheral object. And that measures how fast they can divide their attention between two tasks."
The third test presents an object in the center and the second peripheral object among clutter, which he says "measures your ability to find and select information."
How an adult scores is related to his ability to operate a motor vehicle, Roenker says.
"Individuals who are slow at processing visual information have elevated car accident risks," he adds.
The state of Florida, with its high percentage of elderly drivers, is giving the test a test drive.
"There aren't many alternatives to driving in Florida since there is a lot of urban sprawl," says Robert Sanchez, a spokesman for the Florida Department of Highway Safety and Motor Vehicles. "And while the issue of older drivers has been fairly dormant lately, we have so many retirees."
"Drivers over the age of 85 that have the greatest problem," Sanchez says. "Our statistics of crashes by age groups shows that drivers from ages 65 to 74 have the lowest accident rate of any cohort. After the age of 74, it begins to go up. And beyond the age of 85, the accident rate is higher than [for] the very young, inexperienced driver."
What To Do
For more information on the useful field of vision test, see the National Institute on Aging. And for more on the older driver, see the National Highway Traffic Safety Administration.