Texting strongly affects the time during which a driver can perceive upcoming traffic deceleration, according to research presented at the Association for Research in Vision and Ophthalmology (ARVO) 2023 Annual Meeting, held in New Orleans from April 23 to April 27, 2023. Combining the short working distance of the phone with the larger viewing angle from the roadway may adversely affect the perception of closure, according to the report.
In a study conducted at the Louisiana State University School of Medicine, researcher Wyche Coleman and colleagues enrolled a total of 94 medical students — 47 individuals with emmetropia, 29 contact lens wearers, and 18 individuals with glasses, with best corrected visual acuities of 20/30 or better. The study excluded individuals with monocular vision and patients who lacked stereopsis.
Participants viewed a video that simulated accelerated closure toward the back of a car on a large projector screen. The research team performed a control test without any distractions before introducing a simulated texting exercise during which participants completed a simple math game on a cellphone.
The participants viewed the cellphone at 2 different working distances, 30 cm and 60 cm, while looking straight ahead at an angle parallel to the road plane and 30° down from the road plane. The researchers recorded the time point for closure once the participant stopped the video by depressing a mock brake pedal.
The mean [SD] braking time was 11.5 [4.1] seconds during the controlled simulation, which increased to 17.0 -[3.3] and 15.4 [3.8] seconds while the phone was held parallel to the screen 30 and 60 cm away, respectively (P <.001). Greater increases in mean [SD] braking time occurred when the researchers placed the phone 30° to the screen at both 30 cm (18.6 [4.0] seconds) and 60 cm (17.9 [3.6] seconds; P <.001 for both).
Differences in sex, age, or refractive error were not significant, the report shows.
“Texting significantly affects the time at which a driver can recognize the deceleration of upcoming traffic. Texting at a shorter working distance and a larger viewing angle from the roadway has a deleterious effect on perception of closure,” according to the researchers. “The physiologic reasoning behind these results is likely due to vision blur from accommodation and diplopia as the image falls outside of panum’s fusional space. Safe use of devices in cars could likely be improved by increasing working distance via heads up displays or similar technology.”
Study limitations include a single center design.
This article originally appeared on Ophthalmology Advisor
Coleman W, LoBue S, Martin S, Coleman K, Selchau A, Kavanaugh S. The hazards of texting while driving and the role of visual perception. Poster presented at: The Association for Research in Vision and Ophthalmology (ARVO) 2023 Annual Meeting; April 23-27; Abstract 1491-B0147.