Neuropsychological Aspects of assessing driving safety in the elderly Linas A. Bieliauskas, Ph.D.

Mental Health Service Department of Psychiatry Medical School VA Ann Arbor Healthcare System Department of Psychiatry Medical School Department of Psychology School of Literature, Science and the Arts The University of Michigan

Some general findings Wisconsin Card Sort correlates with ability to maintain center of lane; probably related to self-correction Simple and choice reaction time predict ability of head-injured patients to navigate a track; not in elderly, probably due to different driving habits Reaction time probably predicts potential for accident under challenge Left turns are the most common accidents among the elderly Bieliauskas, L.A., Roper, B.R., Trobe, J., Green, P., & Lacy, M. Cognitive Measures, Driving Safety, and Alzheimer Disease. Clin. Neuropsychol. 1998; 12:206-212.

Cognitive Changes and Retirement among Senior Surgeons (CCRASS): Results from the CCRASS Study Bieliauskas et al., J Am Coll Surg 2008;207:69–79

Number of Impaired Tests by Retirement Status Relative to Age-Corrected Norms

Main Lesson Self-perception of cognitive change with aging is not related to objectively measured change

More Recent Research Drivers with AD commit avg. of 42 safety errors compared to 33 safety errors for those without AD; lane violations most common 4.1 increase in safety errors for 1 SD in cognitive function on composite measure Sig. increases in safety errors in AD with poorer scores on BVRT, Complex Figure-Copy, and Trail Making A Rizzo lab: Dawson et al., Neurol 2009; 72: 521-527

To what are neuropsychological measures related? Not simple ability to drive a car, but ability to respond to challenge For example, we found no difference in accident rates between patients with and without Alzheimer disease; no relationship to neuropsychological data from Alzheimer Disease Center at U. of Michigan (Trobe, J.D., Waller, P.F., Cook-Flannagan, C.A., Teshima, S.M., & Bieliauskas, L.A. Crashes and violations among drivers with Alzheimer disease. Arch. Neurol. 1996; 53:411-416.) Drivers adapt

What is the role of the neuropschologist? While most of us would agree that we will not drive if we perceive our cognitive abilities to be impaired, the accuracy of self-perception of cognitive decline is clearly compromised, even among the brightest The neuropsychologist provides objective evidence of cognitive weakness and decline Validity of neuropsychological measures as predictors of driving safety needs to be continually verified from a political standpoint

Considerations in Evaluating Driving Safety in the Elderly Bieliauskas Brain Injury, March 2005; 19(3): 221–226

Algorithm 1 Brief Attention-based screening measure Simple reaction time UFOV-like test Mass use and inexpensive; secretary-of state office

Algorithm 2 If failed, more extensive cognitive testing measures with the highest odds ratio relationships to simulated crashes might be most efficient Some measure of executive functioning should probably be included, perhaps a computerized version of the Wisconsin Card Sorting Task or a Trail Making Test More expensive and time consuming

Algorithm 3 If performance on this evaluation suggests lack of capacity to drive safely Choosing to accept the decision to suspend driving standardized evaluation, with challenge, in a driving simulator and final decision

Basic need for research Importance of measuring challenge Need to do research in simulator Goal – to start with a simple task which can be done in conjunction with standard driving evaluation Algorithm: Simple Task-> Neuropsychological Testing->Simulator Evaluation