The effect of driving demands on distraction engagement and glance behaviors: Results from naturalistic data

• Published in: Safety science Vol. 136; p. 105123
• Main Authors: Risteska, Martina, Kanaan, Dina, Donmez, Birsen, Winnie Chen, Huei-Yen
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2021
• Subjects: Distracted driving; Environmental demand; Naturalistic driving studies; NEST dataset; Off-road glances; SHRP2; Distracted driving; Off-road glances; NEST dataset; SHRP2; Naturalistic driving studies; Environmental demand
• ISSN: 0925-7535; 1879-1042
• DOI: 10.1016/j.ssci.2020.105123

•Aim: To assess the relation between driving demands and distraction.•A naturalistic driving study dataset was used.•Environmental visual difficulty reduces distraction engagement and off-path glances.•Speed reduces distraction engagement when motor control difficulty is higher.•Drivers over 35 have lower rates of off-path glances compared to younger drivers. To understand drivers’ engagement in distractions and their visual attention allocation under different driving demands. Background: Although distraction increases crash risk, drivers engage in distractions frequently with no negative consequences, likely in part due to their self-regulating behaviors. Prior research revealed a variety of self-regulating behaviors specifically related to cell-phone engagement, but very limited research has investigated whether and how driving demands affect engagement in distractions in general, particularly within a natural setting rather than in the simulator. Method: We used the Naturalistic Engagement in Secondary Tasks (NEST) dataset, a subset of SHRP2 data, to analyze secondary task engagement and off-path (not in direction of travel) eye glances. In addition to assessing their relation to environmental demand, we also considered driver age and chosen speed. Results: Higher visual difficulty environments (characterized as visually complex and/or with low visibility) were associated with a decreased likelihood of secondary task engagement as well as a decrease in off-path glances, particularly longer ones (>2s). Drivers 35 and older had lower rates of off-path glances compared to younger drivers. An increase in speed was associated with a decrease in the likelihood of task engagement in higher motor control difficulty environments (characterized as poor surface condition and/or curved road) but not in lower ones. Conclusion: Drivers appear to modulate their task engagement and off-path glances based on driving demands. However, given that inopportune short off-path glances can lead to crashes, interventions are still needed to help drivers better modulate their distraction engagement.