Reference Electrode Placement in EOG-based Systems Design

The recording of eye movement biopotential is called electrooculogram (EOG). This technique is applied as a diagnostic method in ophthalmology to investigate the human oculomotor system and to control different assistive systems. The first step for developing an EOG-based system is to know in depth the possible sources of interference and the placement of the electrode, especially the reference electrode. They affect the recording of the EOG and pose a challenge to analog signal acquisition. This paper presents a novel study conducted to analyze the influence of these issues in the design of an EOG-based system. To estimate the noise level at each of the reference electrode placements, signal-to-noise-ratio (SNR) and percent root-mean-square difference (PRD) parameters were calculated.