Gaze tracking patterns on different types of traffic risk in early-stage Alzheimer's disease

Many fatal accidents are caused by the driver's inability, upon the occurrence of sudden events, to detect hazards in time, an ability that is based on the driver's eye movement patterns, the detection of involved persons, events, objects, as well as the length of time spent on noticing same. This study intends to compare risk perception and decision-making in high-risk traffic situations between individuals with AD and controls by exploring gaze tracking and hazard detection patterns. The study included 16 individuals with early-stage AD and 26 controls. During the experiment, participants underwent several vision and cognitive tests and watched twelve videos of high-risk traffic situations while their eye movement patterns were being recorded by the eye tracking device, in order to understand how cognitive abilities affect eye movement patterns during high-risk traffic situations. The results revealed poorer cognitive abilities and diminished risk perception in individuals with AD compared with the controls and thus an inability to predict potential accidents. In terms of high-risk traffic situations involving pedestrians, traffic violations by others and view-blocking events, a significant difference in gaze patterns was found between individuals with AD and healthy seniors. The contribution of this study is in elaborating the effect of different traffic event type and specific cognitive abilities on traffic risk-detection in individuals with AD. The results of this study may aid in the formulation of driver licensing policies and the design of traffic scenarios; they also elucidate the driving behaviors of individuals with AD.