Dyslexia can affect many areas of your life, and driving a car is one of them. This is naturally caused by the dyslexic’s reading difficulties, but also by visual processing deficits. Visual processing, also called visual perception, is the way the brain interprets what the eye sees, and visual processing deficits are viewed as a possible cause of dyslexia.
In a study, a team of researchers from Macquarie University in Australia, led by psychological scientist Benjamin Taylor, looked at reading comprehension on the road. After completing measures for adult dyslexia and reading ability, 62 college students completed simulated drives through a series of city, suburban, and rural environments with varying levels of traffic. After each round of driving, participants were asked about their perception and comprehension of road signs (i.e. “No Left Turn” or “Railroad Crossing”) that they had passed during the drive.
The results suggest that participants who had higher dyslexia scores tended to have greater difficulty comprehending road signs, particularly road signs that contained words and no images.
What if words play no role?
In one study that compared dyslexic readers’ ability to identify visual signs and symbols without requiring the naming of these symbols, Gregory Brachacki and colleagues at Sheffield University found that dyslexics are slower to interpret traffic signs. They tested ten adults with dyslexia and 11 controls on their ability to differentiate between real and false traffic signs. The adults with dyslexia recognized the traffic signs significantly less well than did the controls. Furthermore, whereas for the controls there was a significant correlation between traffic sign recognition and driving experience, no such correlation was found for the adults with dyslexia.
In another study, researcher Hermundur Sigmundsson and his colleagues at the Norwegian University of Science and Technology in Trondheim gave 17 volunteers, six of whom were dyslexic, two different tests. The first involved a 4-minute drive along a simulated country road at 50 to 80 kilometers per hour. In the second task, the volunteers drove through a city at lower speeds for 10 minutes.
The simulator flashed up traffic signs in the drivers’ field of view and measured how quickly they responded by pushing a button or saying “now”. In the rural drive, the signs appeared directly ahead, while in the city they appeared in a variety of places.
The six dyslexic drivers took on average 0.13 seconds longer to react during the rural drive than the non-dyslexic controls and were 0.19 seconds slower in the city, where the simulated environment was more complex. In both tests the controls took around 0.6 seconds to respond, so the dyslexic drivers were experiencing a delay of 20 to 30%.
“Drivers just over the UK’s (United Kingdom’s) alcohol limit, which can be exceeded by drinking two pints of beer, are typically 10 percent slower than normal to react,” according to the New Scientist magazine. This means that dyslexia can slow a driver’s reaction time as much as drinking moderate amounts of alcohol, according to the study.
What do we learn?
These studies confirm that dyslexics have deficits in visual processing, especially form perception and visual processing speed.
Form perception is an aspect of perception and concerns the processes involved in distinguishing shapes through the senses. Form perception is one of the most basic visual discriminations acquired by humans in childhood. A child with poor form perception is highly likely to be diagnosed with a learning disability, since almost all learning activities require some type of form perception, most importantly the ability to read. A child who has trouble perceiving the form of the letters, syllables or words, will have difficulties in learning the alphabet or in learning to read. The discrimination of letters is the most important skill in the early stages of reading.
Visual processing speed can be defined as how fast a person can look at and process information on a task that does not take any more thinking than noticing the differences or sameness in the objects shown.
How can Edublox help?
Edublox programs are effective in overcoming reading and other learning difficulties by addressing the underlying shortcomings that interfere with academic performance. Underlying shortcomings include poor form perception and slow visual processing speed.