Risky driving in fog : Psychological explanations

Abstract

Fog doubles the risk of accidents and modifies driving behaviour in a way that leads to greater risk-taking. Traffic studies indicate that most drivers adopt excessive speeds and insufficient headways in foggy conditions. Yet our understanding of the psychological processes underlying this common but unsuitable behaviour, and ghe effectiveness of road safety measures, remain limited. Two main hypotheses have been put forward. The first one stemming from social psychology, evokes a deterioration of social communication between drivers in fog and explains risky behaviour by processes of social comparison and psychological reactance. The second one, proceeding from cognitive psychology, refers to perceptual difficulties. The reduction of visibility and preview distance bears on obstacle detection and trajectory control. The drastic reduction of visual information and in particular contrast attenuation, is likely to affect speed and distance perception as well as visual thresholds of motion perception. This paper proposes to examine the existing experimental evidence and to evaluate the importance of the various psychological processes in the emergence of risky behaviour in fog