I found very little information useful for explaining why autistics have a difficult time driving in traffic. The absence of information surprises me, since I know so many autistics (of the so-called "high-functioning variety") who do not drive. Instead, they rely on relatives or public transportation for their travel needs. I find plenty of discussions on the issue written by autistics who don't drive
, autistics who drive
, and advocacy groups
. There are even special training programs
just to teach driving to autistics. Nobody, though, enumerates the individual stresses of driving.
The best summary I could find was a New York Times health blog
that mentioned only 24% of autistic adults were "independent drivers". The key point in that article was a quote by a medical advisor on safety issues for Quebec’s government-run auto insurance and licensing agency. I'll begin my self-examination with that starting point.
"Driving is a social act." - Dr. Jamie Dow
I think the stressors are these:1) Self-interested driving by others adds to my mental drain.
Learning and following the rules of the road is just a matter of time and practice. Not all drivers, however, follow those rules. It means that I have to "get into other people's heads" to figure out their potential actions in spite of the rules. I try to avoid figuring out other people, so situations that require it simply add to my overall stress. I know that I my stress increases every time I see someone darting to exits at the last possible moment in order to "cut in line" ahead of the long line of people who properly waited their turn in queue. Evidence of self-interest competing with orderly rules will add to my stress.
The worst stress in these situations is seeing two drivers from opposite lanes decide at the same moment to merge into the same middle lane. I see the crossed trajectories, I deduce that they don't see each other, I accept that I can't warn them, so all I can do is hit my breaks to put more distance between me and the impending collision. Each step of that mental process drains energy by demanding immediate attention. I don't want to think about what other drivers (or people in general) are thinking.2) All non-conformity adds to my mental drain, actually.
Those drivers who treat the commute as a personal challenge add to the computational complexity that I must perform. They drive at different speeds, they dart between lanes, and trying to build my mental map of the "flow" of traffic (even disregarding the drivers' intentions) gets so much more difficult when I have to account for multiple non-conforming vehicles. Their utterly unnecessary driving pattern and my annoyance at it both add to my stress.
3) Multiple simultaneous identification requires energy.
When everyone drives in the same pattern, then it's easy to maintain "the flow" of traffic. I join the metaphorical school of fish rather than remaining one of a multitude of independent fish. With everyone changing speeds and directions, though, I must map each vehicle on the road and maintain its trajectory within my mental environmental map. Mapping requires concentration, and concentration requires energy. I don't know, but can't stress be defined as the undesired use of mental energy?
Seeing all of the trees requires a lot more brain power than simply seeing the forest. Driving, unfortunately, requires seeing each individual vehicle and pedestrian and tracking their changing trajectories. Permutation explosion is never a good thing. The convoy experience is much less mentally taxing, but city commutes do not happen by convoy unless the congestion is so bad that everyone is barely traveling at all.4) Social negotiation adds to my stress.
I sometimes find myself wanting to change lanes to deliberately impede the progress of unpredictable drivers, to make the point that if every driver on the road behaved like they did, then the commute for everyone becomes a permutation explosion of unreasonable complexity. I don't pursue it, of course, but the idea of such confrontation adds to my stress.
When a driver is polite and signals with plenty of lead time that they want to enter ahead of me, it still is an unsolicited social negotiation. Driving requires acceptance of these unexpected social entanglements. They are brief, yes, but still undesired. Even when I am the driver needing to change lanes (entirely necessary, not frivolous bypassing of slower vehicles), I notice a slight increase in my stress since I must now socially procure "entry" with a new crowd. It's only a small stress, I agree, but it is non-zero and adds to the cumulative experience.5) Consequences are worrisome.
It also adds a non-zero amount of stress to my mind simply knowing that the consequences of any failure are potentially severe. I mean primarily medical consequences, but to a lesser extent there are also the legal consequences (ticket fines, license revocation, etc.). The "impending doom" increases the focus necessary to concentrate on safe navigation.6) Good viewing is mandatory.
Good lighting is necessary to make this tracking process easier. Any environmental condition that reduces visual clarity will add to stress by reducing the amount of time available to see objects and computer their characteristics. These negative conditions include rain, snow, fog, darkness, glare from sunlight or approaching headlights, and probably lots of other factors.Conclusion) Driving is both complicated and social.
Not only does driving require tracking "objects" on different and changing trajectories, but it also requires "people" skills by intuiting others' intentions and negotiating entry with different groups. It's a wonder, actually, that autistics succeed at this process at all. Normally, a simple and short commute does not bother me in any noticeable way, so I guess I should consider myself talented in this regard. I suspect now, though, that commute stress might be the primary reason that I very rarely travel for personal vacations. This deep self-inquiry, even done in the safety of my desk chair and comfort of my bath robe, leaves my stress at noticeable levels. Time to take a break for a drink of water and some mindless television as a distraction.edit 2013.10.28:
P.S. I realized during the commute today that there's another issue that I missed completely. The individual stresses while driving will repeat continuously. With little time to de-stress and return to "resting state", the bloodstream instead has to cope with additional stress chemicals being released with each new detail demanding immediate attention. It builds upon itself, making the whole experience an ordeal worse than its individual parts.