P300 based stereo localization of single frequency audio stimulus

P300 is widely used for developing Brain-Computer Interfaces (BCIs) and also in clinical applications for research and diagnosis. In this study, a novel way of performing oddball paradigm by stereo-localization of single frequency audio stimulus is proposed. In the proposed stereo oddball technique, a single frequency audio stimulus is presented to the subject in alternating ears with one ear being the target and the other non-target. Non-target is presented more often than target. The experiments are conducted for two configurations, left (target) - right (non-target) and right (target) - left (non-target). Noninvasive Electroencephalogram (EEG) signals are collected for the above mentioned protocol and the P300 component is detected using event-related potentials (ERPs) and analyzed. The proposed Stereo oddball technique is also compared with classical (target and non-target are beeps of different frequency) oddball technique, where the stimulus is presented simultaneously to both ears. The P300 responses are also analyzed using both temporal regions individually. Despite differing inputs(single frequency and dual frequency), similar P300 responses are observed for stereo localized and binaural stimuli presentations.