Purpose.
Driving is essentially a visuomotor task, and there is now compelling evidence that the disproportionate number of road accidents under night driving conditions is linked to changes in visual performance resulting from reduced lighting. The objective of this article is to establish the extent to which vision is either rod-or cone-dominated under night driving conditions.
Methods.
Visual thresholds are measured under lighting conditions that simulate urban lighting. Dark adaptation curves are obtained under three ambient lighting conditions ranging from low (0.1 cd/m2) to high (5 cd/m2) mesopic levels of retinal adaptation using circular discs of different sizes (1°, 2°, 3°, and 5°) presented at retinal eccentricities of 0°, 10°, 20°, 30°, and 40°.