It’s fair to say regarding what we’ve been discussing thus far, that individuals with AS tend to have difficulty with visual-spatial judgement, and there is evidence that this may involve under-connectivity in dorsal stream function.
Many of you (Lord, I hope there are at least a few of you left) will remember the inimitable Johnny Carson and his great routines as the slick salesman, Art Fern. In describing how to drive to his location, he would deadpan: How do you get there? Let me tell you friends, how do you get there! You take the San Diego Freeway to the Ventura Freeway. You drive to the Slauson Cutoff, get out of your car, cut off your Slauson, get back in your car, then you drive six miles till you see the Giant Neon Vice-Squad Cop. Forks in the road can be challenging visual-spatial tasks, and we have one on the way to our office that rivals the celebrated Slauson cutoff. Our famous fork actually made it into a televised scene of The Sopranos, quite appropriate because you’re always looking over your shoulder waiting for an accident to happen. Let me give you the setup and then we’ll look at the photos.
Crossing over the George Washington Bridge out of the northern regions of New York City deposits you onto Route 4, a three lane highway on which you travel West for approximately 12 miles to our office. The trip is very straightforward until you come to a fork in the road, about a mile before our office, where you have a decision to make. To continue on Route 4 there are two lanes that curve a bit to the left, becoming a local route with traffic lights at the southern foot of town. If you want to continue toward our office you have to merge toward the right, following the overhead sign that says “208 North – Oakland”. To the extreme right is an exit for Saddle River Rd., marking the northern edge of town. Hence a three-pronged fork.
Here is the approach to our version of the Slauson Cutoff. Note that as you approach the fork, there should be some indication about which lanes lead to which fork, but there isn’t. If you’re not familiar with the road, you’ll be crisscrossing in front of other cars at the last moment to find the correct prong of the fork. If you know the road, and you’ve moved over so that you’re in the center lanes, you have to anticipate that the car in the lane next to you may not realize he has to move over and will try to cut over rightward at the last moment. He can’t slow down because the traffic behind him is going at a fast clip and curving leftward. Alot of visual-spatial judgement is required on the part of all drivers here, and there are numerous other visual clues. For example, if the driver of two cars in front of you hits his brakes because he’s getting cut off, and the brake lights of the car ahead of you don’t go on, you know that he is either going to stop short and you must slow down in anticipation. Rather than defensive driving, some prefer the term anticipatory driving.
There wasn’t dense traffic when I took these photos, so the blue car in front of me was able to figure out what to do. When traffic is dense and fast, there’s a more serious risk of having your Slauson cut off.
In discussions about safety in driving, we tend to pay much more attention to impairment of cognitive judgements among older drivers. Enter the search word “Asperger’s” on the website of The National Highway Traffic Safety Administration (NHTSA) and you’ll find nothing. Enter the search word “Autism” and you’ll get a few items, only one of which pertains directly to driver safety. It is a PDF regarding Pedal Application Errors, and it is noteworthy that it says reports that clients who perform poorly in clinical tests of executive function made pedal application errors, and that this was not limited to older drivers but included young clients diagnosed with Autism and with ADHD.
The AMA, in conjunction with the NHTSA and DOT, published A Physician’s Guide to Assessing and Counseling Older Drivers. Chapter 4 of the Guide notes the utility of various visual, motor, and cognitive tests and one of the clinical probes that has impressive correlation with cognitive judgement and driving performance is the Trail Making Test, Part B (TMT-B). The NHTSA sponsored a wonderful study conducted in Maryland and published in 2003 which includes the TMT-B as well as a visual closure test, a useful field of view test, and several other perceptual-cognitive probes. Again they concluded that tests of this nature correlated significantly with driving performance.
In recognition of the void in extending risk factors to individuals with AS/HFA, The Association for Driver Rehabilitation Specialists has recently added an excellent FACT SHEET on Asperger’s Syndrome and High Functioning Autism which includes Information Processing, Motor Coordination, Executive Function, and Social Skills. They suggest that an evaluation should include:
1) A review of medical history and medication
4) Assessment of Life Skills
5) Activities that assess visual and cognitive processing skills for driving
6) Behind-the-Wheel Evaluation or simulated driving activities to assess motor coordination