A comparative approach to identify unsafe older drivers.

The identification of unsafe older drivers is a current and important challenge. In the present research, a comparative approach was used in which the on road driving errors and expert evaluations of older drivers with clinically significant declines in mental abilities (N = 155) were compared to the errors and evaluations of a normal elderly control group (N = 68) and a normal younger control group (N = 30). The results indicate that the conventional criteria used in North America for licensing new drivers is inappropriate for license removal in experienced drivers. The results also indicate that hazardous errors were the single best indicator of membership in the group of older drivers with clinical impairment. This group also differs from the two normal control groups on turn positioning errors, minor positioning errors and overcautiousness. All groups differ from each other on scanning errors. A regression analysis further indicated that the five driving errors listed above accounted for over 57% of the variance associated with global ratings provided by expert driving instructors.

Age differences in word finding in discourse and nondiscourse situations.

Measures of word finding in discourse (video description task) and nondiscourse situations (word fluency tasks) were obtained from a sample of 90 community-dwelling healthy adults. Age differences were found in the accuracy and uncertainty of the labels used to refer to the characters and objects depicted in the video description task and in the number of correct responses in the category fluency task. There was a significant amount of shared variance between the 2 types of tasks. More important, there was a significant amount of variance in the video discourse task associated with age that was independent of performance in the word fluency task. The communicative impact of a word-finding problem and need for discourse level study are discussed.

Communicative function in patients with questionable Alzheimer's disease.

The communicative skills of patients with questionable Alzheimer's disease (AD) were examined by having patients describe events shown in a silent video cartoon. As anticipated, questionable AD patients provided fewer clauses in their descriptions than did education- and age-matched controls. This finding was independent of differences in word finding ability. More important, the patients failed to describe as many of the thematically important events as did the controls, a difference that affected the overall informativeness of the communication. Even though the patients were sensitive to event importance, there was no evidence of compensation in their descriptions (i.e., a greater concentration of important events). Several interpretations are presented that focus on possible deficits in the pragmatic or semantic systems of language or both as an early symptom of Alzheimer's disease.