Gaze behavior of the visually impaired during street crossing.

PURPOSE: <br/><br/>This study explored the gaze patterns of fully sighted and visually impaired subjects during the high-risk activity of crossing the street.<br/><br/>METHODS: <br/><br/>Gaze behavior of 12 fully sighted subjects, nine with visual impairment resulting from age-related macular degeneration and 12 with impairment resulting from glaucoma, was monitored using a portable eye tracker as they crossed at two unfamiliar intersections.<br/><br/>RESULTS: <br/><br/>All subject groups fixated primarily on vehicles and crossing elements but changed their fixation behavior as they moved from "walking to the curb" to "standing at the curb" and to "crossing the street." A comparison of where subjects fixated in the 4-second time period before crossing showed that the fully sighted who waited for the light to change fixated on the light, whereas the fully sighted who crossed early fixated primarily on vehicles. Visually impaired subjects crossing early or waiting for the light fixate primarily on vehicles.<br/><br/>CONCLUSIONS: <br/><br/>Vision status affects fixation allocation while performing the high-risk activity of street crossing. Crossing decision-making strategy corresponds to fixation behavior only for the fully sighted subjects.<br/>