Quantifying the relationship between auditory distractions, reaction time, and crash probability

Mobile phones and listening to music while driving have become increasingly common behaviors despite the known risks they pose. The objective of this study is to examine the impact of phone call and listening to music on drivers' reaction times and to assess how these distractions influence the probability of crashes. Seventy seven participants with different age groups and gender were tested for their reaction time under three different environmental conditions: Normal, listening to music, and talking on the phone. Further, an Unmanned Aerial Vehicle (UAV) was used to collect traffic data on the National Highway, Signalized Intersection, and Toll Plaza. An automatic trajectory extraction tool was used to find the Time to Collision (TTC) values between different leader-follower pairs at all these locations. Reaction time variation under various testing conditions was plotted against the TTC values obtained from the field data to evaluate the real field accident probability. Under Normal condition, the average reaction times are 0.704 s for females and 0.727 s for males. With Music, the averages slightly increase to 0.743 s for females and 0.764 s for males. The Call condition shows a more pronounced effect, with average reaction times jumping to 0.800 s for females and 0.874 s for males. The study reveals that listening to music resulted in a 5.281 % increase in reaction time and a 10.57 % increase in crash probability compared to normal conditions. Being on a call had a much larger impact, resulting in an 18.47 % increase in reaction time and a 27.35 % increase in crash probability compared to normal conditions. These findings highlight the importance of avoiding distractions while driving and suggest that phone calls should be avoided while behind the wheel. The study can be used to develop policies regarding the use of mobile phones and also to compare accident risk across different traffic facilities.