Absence of concentration and coherence in a subject is detected by evaluating the success which the subject has in moving a first object into engagement with a second object over a path which permits the first object to deviate from direct movement to the second object. The moving operation which the subject carries out is not directly visible to the subject; he sees only direct and reverse images of the movement which merge when the second object is engaged by the first object. Deviations from direct movement appear oppositely on the direct and reverse images and the images cannot be coordinated by a subject lacking concentration and coherence. The invention is applied to the movement of a connecting mechanism to energize the ignition of an automotive vehicle.
Detection of absence of concentration and coherence in a subject