ABSTRACT
Driver fatigue contributes to 20 to 30% of road crashes globally. Light could be an effective countermeasure for fatigue by improving human alertness via several direct and indirect neural pathways. Laboratory studies and applied work have confirmed the improving effects of light on neurophysiological (brain and heart activity), subjective alertness, and behavioural outcomes of alertness (reaction times and attention lapses). Limited naturalistic or simulated driving studies have also reported improved brain activity, reaction time, and driving performance (reduced terminal crashes, inappropriate line crossings, lateral lane position variability and steering wheel variability) with various light profiles. The lighting setups utilised in these studies are custom-made systems with varying types, shapes, sizes, car placements, and ambient light adaptability. Large-scale naturalistic driving studies are required to validate the alerting effects of light in the real world and explore its potential side effects (e.g., contrast effects, uncomfortable spectral distributions, eye discomfort and irritation) or safety hazards (driver distraction) on the road.
