A computer diagnosing system of dementia using smooth pursuit oculogyration

Abstract

Human smooth pursuit eye movement has been studied aiming to develop a new dementia diagnosing system. The glass-type measuring unit was installed with a small LCD monitor and a CCD digital camera as well as a built-in image-processing unit. The subjects are 19 demented patients, 18 normal elders and 7 healthy young volunteers. The adopted velocities of pursuing target are 300, 400 and 500 pixel/s. As diagnosing parameters, we have adopted the switching time of internal & external rectus muscles, max velocities and peaks of oculogyration. As a conclusion, the real-time measurement of human oculogyration seems to become a new diagnosing method of the dementia because the smooth pursuit of the demented patients has presented clear deviations from the healthy elders. Especially the pursuit velocity, peak value, switching time and correlation coefficient seems to be very useful to discriminate the demented patients from the healthy elder subjects objectively.