Bad Driving May Be In The Genes
UC Irvine neuroscientists have discovered that individuals with a gene variant - which limits the availability of the protein, brain-derived neurotrophic factor (BDNF) - perform more than 20 percent worse on driving tests than those people without the variant. About 30% of Americans will have the gene variant.
"These people make more errors from the get-go, and they forget more of what they learned after time away," said Dr. Steven Cramer, neurology associate professor and senior author of the study published recently in the journal Cerebral Cortex.
BDNF supports communication among brain cells and keeps memory strong. When a person in engaged in a particular task, BDNF is secreted in the brain area connected with that activity to help the body respond. Previous studies have demonstrated that people with the gene variant have a smaller portion of the brain stimulated when performing tasks. The researchers wondered if the variant could affect an activity such as driving.
The driving test was taken by 29 people - 22 without the gene variant and seven with it. They were asked to drive 15 laps on a simulator that required them to learn the nuances of a track programmed to have difficult curves and turns. Researchers recorded how well they stayed on the course over time. Four days later, the test was repeated.
Results showed that people with the variant did worse on both tests than the other participants, and they remembered less the second time. "Behavior derives from dozens and dozens of neurophysiologic events, so it's somewhat surprising this exercise bore fruit," Cramer said.
The gene variant isn't always bad, though. Studies have found that people with it maintain their usual mental sharpness longer than those without it when neurodegenerative diseases such as Parkinson's, Huntington's and multiple sclerosis are present.
"It's as if nature is trying to determine the best approach," Cramer said. "If you want to learn a new skill or have had a stroke and need to regenerate brain cells, there's evidence that having the variant is not good. But if you've got a disease that affects cognitive function, there's evidence it can act in your favor. The variant brings a different balance between flexibility and stability."
A test to determine whether someone has the gene variant is not commercially available.
"I'd be curious to know the genetics of people who get into car crashes," Cramer said. "I wonder if the accident rate is higher for drivers with the variant."
Post new comment