The influence of depression symptoms and antidepressant medications on cognition and driving performance

Research that has examined the influence of depression symptoms and antidepressant medications on driving performance has revealed inconclusive findings (Brunnauer, Laux, Geiger, Soyka, & Moller, 2006; Bulmash et al., 2006; Ramaekers, 2003). The purpose of the present study was to elucidate the influence of depression symptoms and antidepressant medications on cognition and driving performances using self-report measures as well as an ecologically valid method measure, a driving simulator, and a clinical population. Two hundred and thirty-three drivers ranging in age from 18 to 35 years {M= 21.88; SD = 3.90 years) completed a screening measure that examined depressive and anxious symptoms, medication use, and self-reported driving behaviour on the Driving Behaviour Questionnaire (DBQ). Forty-three participants ranging in age from 18 to 35 {M= 24.24; SD = 5.05 years) also attended a laboratory session and completed a series of questionnaires designed to measure depression driving habits, cognitive psychomotor functioning, and a diagnostic measure of MDD, two computerized tasks (one to measure attention and one to assess processing speed), and a 45 min simulated drive. In the overall sample, twenty-four (10.2%) participants were taking at least one antidepressant. Mean scores for depressive symptoms {M= 11.09; SD = 9.87) fell in the minimal range on the Beck Depression lnventory-11 (BDI-Il). A shortened version of the DBQ was created using this younger Canadian sample and correlation coefficients between the short and long version were excellent, ranging from .91 to .94. Overall, depressive symptoms and antidepressant use displayed little relationship to self-reported driving behaviour or driving performance on the driving simulator. However, our results do suggest that age (B= .12) and the cognitive/affective (B = .12) impairments on the BDI-II are statistically significantly related to increased self-reported absent-minded driving behaviour {p = .03). Overall depressive symptoms {B = -2.48) and cognitive/affective {B = 3.45) impairments were also related to inattention on a computerized task measuring attention {p < .05). The cognitive and affective impairments in depression were also positively related to visual perceptual ability {B = 2.02). The overall patterns of self-report data, neuropsychological data, and behavioural data suggest that although there is some consistency between self-report measures and neuropsychological data, this does not necessarily mean these impairments in attention translate into actual driving impairments on the simulator. Future studies could conduct a similar study using on-road performance as the behavioural measure of driving performance