Android based EEG speller for the disabled

Steady State Visually Evoked Potential (SSVEP) is the electro encephalograph (EEG) response observed at the occipital region of the brain to a visual stimulation having a periodic intensity variation. When the retina is excited by a visual stimulus ranging from 3.5 Hz to 75 Hz, the brain generates electrical activity at the same or multiples of frequency of the visual stimulus. SSVEP response can be used to determine the light source the subject is viewing and can form an useful part of a brain machine interface (BMI). Here we present an Android Application that produces visual stimuli, receives EEG signals and performs real time signal processing that enables the classification of the signal spectrum. This is aimed at providing a speller technology for the disabled.