Asymmetric Shifts in Risk Perception: Evaluating Driver Responses to Traffic Density Transitions

This study examined how transitions in traffic density and speed affect drivers’ risk perception over time. Nineteen participants viewed driving simulation recordings featured urban-highway transitions: high-to-low and low-to-high transitions in traffic density and speed. Subjective risk perception ratings were collected at three time points: before the transition ( Pre ), shortly after ( Transition ), and following a short adaptation period ( Post ). Results indicated that risk perception dropped rapidly when traffic density decreased and spiked immediately when density increased, followed by gradual adaptation. Speed reductions unexpectedly increased perceived risk, while speed increases led to delayed decreases in perceived risk. Findings highlight the need for traffic systems and driver assistance technologies to consider how perceived risk shifts asymmetrically during environmental transitions. Future work should employ interactive simulations and control for visual and structural variables to isolate contributing factors more precisely.