Glare Impairs Response Inhibition: Potential Impacts of Solar Panels on Highway Driving Safety

The setting of photovoltaic (PV) solar panels on highway slopes could cause glare, which may distract drivers’ visual attention and driving behavior. To investigate the influence of glare on drivers’ response inhibition, this exploratory study adopts a within-subject design experiment (n = 34) with simulated glare in the laboratory. Response inhibition was assessed by the stop signal task (SST). The reaction time of response inhibition was significantly longer under glare compared to the control condition (t (33) = 4.255, p < 0.001, Cohen’s d = 1.163, 95% CI: [34, 109]), but there were no significant differences between the glare and control conditions for the accuracy of response inhibition, the accuracy of visual discrimination, or the reaction time of visual discrimination. These findings suggest that glare may impair driving behavior by delaying drivers’ reaction especially when they have to overcome an inappropriate response in an emergency.