A Study on the Possibility of Applying Subliminal Visual Cue for Guiding Subject’s Attention

This paper presents a new warning method for increasing drivers’ sensitivity for recognizing hazardous factors in the driving environment. The method is based on a subliminal effect. In this study, the presentation of a visual cue at a lower contrast ratio than that of the background scenery was investigated as subliminal visual information instead of flashing information quickly. This method was chosen in consideration of its use in real-world driving situations where changes in ambient brightness are among the biggest visual disturbances experienced by drivers. Accordingly, it is necessary to have amethod that is applicable in the context of dynamic changes in brightness. The results of many experiments performed with a threedimensional head-mounted display show that the response time for detecting a flashing mark tended to decrease when a subliminal mark was shown in advance. A priming effect is observed for subliminal visual information. This paper also proposes a scenario for implementing this method in real vehicles.