Factors promoting accidents involving elderly pedestrians and drivers.

This paper focuses on research carried out at the age and cognitive performance research centre at the University of Manchester into the understanding and measurement of changes in driving performance caused by age. The paper begins with a review of other laboratory research in this field, pointing out that older people, including elderly drivers, show much greater variability in performance at skilled tasks than do young adults. Thus generalisations about the precise ages at which particular difficulties may be expected to appear are unreliable, and should not be allowed to influence legislation. Besides this increase in variability in ability with age it does that the competence of many elderly drivers may be supported by the skills that they have acquired over a long lifetime and which they can maintain even into their late 70s or early 80s. However a necessary caveat is that even long-acquired and well-maintained skills gradually become less valuable, and ultimately unusable, because of a general decline in information processing speed that accompanies normal ageing. Besides its obvious direct consequences in slowing performance, this decline in available information processing capacity makes older people less sensitive at monitoring and detecting adverse changes in their own sensory abilities and driving performance. This may be especially the case when older individuals have adapted their driving routines to seek out increasingly undemanding road and traffic conditions. Here lack of feed back about actual changes in the true limits of their performance, coupled with insensitivity to, and forgetfulness of, such feedback as they receive may lead older drivers to unjustified optimism about their current abilities and so betray them when they must suddenly cope with unforeseeable and unavoidable complex decisions. There are, however, grounds for cautious optimism both in the extent to which highly practised skills can be maintained until very late in life and in the extent to which the provision of more adequate feedback on current sensory abilities, and perhaps on driving performance, can allow older people better to recognise and adapt to the changes they must inevitably experience.