EGG (Electroglottograph) Display

The Electroglottograph, or short “EGG” is a physiological signal that allows us to follow the vibrations of the vocal folds that produce the primary sound at the glottis. A small high-frequency current runs between two electrodes that are held in place on either side of the larynx. The conductance between the electrodes increases by a small amount when the vocal folds make contact, initiating the closed phase of the glottis. The conductance decreases again as the glottis opens. These modulations in conductance give us the EGG signal, useful as a measure of contact between the vocal folds.