An electro-oculogram (EOG) was derived from potentials recorded from electrodes
placed above and below the eye during voluntary vertical eye movements. Concurrent measurement
of the amplitude of eye blink potentials recorded from the same electrodes produced curves
which were highly correlated with the EOG measured from stereotyped eye movements. Recordings
from a patient with a missing globe, owing to trauma, revealed eye movement and blink responses
only from the intact side. A patient with no light perception showed blink responses which were less
variable than responses measured during attempts voluntarily to move the eyes vertically in 600
excursions. An EOG calculated by measurement of eye blink potentials may be possible in clinical
situations where traditional electro-oculography techniques are not feasible.
reaction to changing ambient light conditions may be checked to determine if a live eye is in the
sensor’s field of view [46]. In addition, challenge-response transactions may be implemented
wherein the person under test is asked to blink or move their eyes in a certain direction to ensure
that the random instructions are carried out properly [47].