Abstract
Short-term memory test and spatial recognition test with images are investigated for detecting dementia at the early stage or pre-clinical stage. It is important to track subjects' eye-gaze points on images of the test. The authors revealed the difficulty of using eye-gaze tracking system, which is on the market, to elderly people by the results of experiment with a total of 80 subjects included their age of seventies to nineties. The factors of difficulty were the physical aging such as curve of back born, wrinkles on eyelid, watery eye, scar of surgery for cataract, and presbyopia. As the solutions, the authors unified CCD camera with Face-Mounted Display and decided the best position of CCD camera and Infrared LED (IRED). The authors also adopted the method of tracking center coordinate of pupil by image processing instead of corneal reflection method. The experimental results showed that eye-gaze tracking with FMD-type eye camera was successful.
