The aging process may also affect cognitive skills. Short-term memory loss, for instance, can impair driving skills by interfering with a person's ability to process information efficiently when merging with traffic or changing lanes. Such difficulties are magnified when the older driver performs these driving skills under stressful conditions. The higher incidence of cognitive impairment, particularly dementia, among older adults produces an increased risk of accident involvement.
As a group, persons age 65 and older are relatively safe drivers. Although they represent 14 percent of all licensed drivers, they are involved in only 8 percent of police-reported crashes and 11 percent of fatal crashes. This can be compared to drivers age 16 to 24, who are involved in 26 percent of police-reported crashes and 26 percent of fatal crashes, but represent only 14 percent of licensed drivers.