I'm just reading a fascinating article by Ray Fuller, Department of Psychology, Trinity College, Dublin about driver behaviour in some publication called Accident Prevention and Analysis ( joy of working in a university where journal access is quite wide).
The bit that interested me is this:
Quote:
A recent conceptualization of what determines driving task difficulty has been presented in the task–capability interface (TCI) model (see Fuller, 2000 for the initial version of this model and Fuller and Santos, 2002 for a more developed version). In this model, task difficulty arises out of the dynamic interface between the demands of the driving task and the capability of the driver. Where capability exceeds demand, the task is easy; where capability equals demand the driver is operating at the limits of his/her capability and the task is very difficult. Where demand exceeds capability, then the task is by definition just too difficult and the driver fails at the task, loss of control occurs, and this perhaps leads to a collision or the vehicle careering off the roadway. Thus in essence, task difficulty is inversely proportional to the difference between task demand and driver capability. With a static level of capability, any event that pushes up task demand will therefore reduce this critical difference, increase task difficulty and potentially challenge safety. For instance, the use of a mobile phone can be an additional task, which pushes demand beyond driver capability. Violanti and Marshall (1996) report that cellular phone use while driving increases the probability of collision by 500%. Note that in this formulation task difficulty is independent of task complexity. If the driver's capability far exceeds the demands of a complex task, the task is perceived as relatively easy. Similarly, a simple task will be challenging if the demands exceed the driver's available capability.
Sometimes the actions of another road user can rescue the situation from imminent catastrophe, such as a pedestrian leaping out of the path of an out-of-control vehicle. In such an instance the pedestrian effectively changes task demand at the very last moment (see Fig. 1). Alternatively, the driver may be able to recover from the loss-of-control situation and avoid an impending collision or road run-off.
At the threshold where task demand begins to exceed capability, we need not necessarily expect a sudden and catastrophic breakdown of control but rather a more fragmented degradation. As suggested by Wickens and Hollands (2000), quality of performance may deteriorate (such as the driver losing tight control of lane positioning or situation awareness; see, for example, the simulator study by van der Hulst et al., 2001), or low priority task elements may be dumped (such as mirror checking). In more extreme cases, high priority tasks may suffer a similar fate (such as looking ahead). However, in many instances where demand exceeds capability, the increased demands are such that the driver is simply unable to maintain the desired trajectory, avoid an obstacle or stop in time.
I am definitely seeing this on some of the drivers around here. The tunnel vision thing is becoming quite common. I thought it was out of rudeness or laziness but this perhaps suggests that either driving today is becoming a lot harder or the capability of a lot of drivers is falling so low priorty tasks are being ignored as they can't cope with doing everything they should. Does this mean that hazard density is increasing or congestion is making it much harder for most people to drive safely? Are people now just looking out for cameras and their speedos and bumping other tasks? Do people feel so demonized by anti motoring authorities that they just don't care whether they drive badly as long as they don't get pinged?