Literature Review of Electrooculography (EOG)

WHAT IS ELECTRO-OCULOGRAPHY (EOG)???

An Electrooculogram or EOG is the resulting signal of the potential difference caused by eye movements. The voltage difference is measured between the cornea and the retina. The resting potential ranges from 0.4mV to 1mV and a pair of electrodes are commonly used to detect this signal, but the voltage difference when there's an eye movement can be as small as just some microvolts. Depending on the eyes' position, an electrode is more positive or negative with respect to the ground electrode. Therefore, the recorded signal is either negative or positive when moving the eyes.

 

WHO DISCOVERED OEG???

In 1849, Du Bios-Reymond found there was a certain relationship between eye movements and electrode potentials from the skin surface. Medical studies proved that the potential difference, which is commonly called the resting potential, arose from hyperpolarisations and dehyperpolarisations existing between the cornea and the retina. The resting current flows continuously from the retina side to the cornea side, so that an electrical field comes into being with a negative pole at the retina and a positive pole at the cornea. This field changes orientation as the eyeballs rotate. Therefore, a human eyeball can be considered as a spherical battery that the centre of cornea is positive and the retina is negative.

references:

wikipedia-eog

technicaljournalsonline.com