Problem To achieve early detection and prevention of mild dementia by viewing with both left and right eyes in a balanced manner which by stimulating and activating the left brain and right brain in a balanced manner easily alleviates the progression of cognitive function decline and promotes recovery of cerebral vision. Solution The invention consists of: generating a stereoscopic image area A2 for displaying stereoscopic images displaying a plurality of objects Ob21 Ob22 within a virtual space constructed in the stereoscopic image area A2 with the positions or orientations thereof changing rotating the plurality of objects Ob21 Ob22 at an arbitrary speed centered on an arbitrary centroid position P2 established within the virtual space and also changing the color of the objects at an arbitrary timing and duration and recording as a test result of spatial recognition ability and situational judgment ability the time difference between the timing and duration of the change in color of the objects Ob21 Ob22 and a user operation on user interfaces G22 G23 as well as the accuracy of the user operation.
