An SSVEP-Based Brain Computer Interface Prototype for Assisted Living

Expressing basic needs may seem like a simple task, but not for those with deteriorated or lost ability to speak and move. This paper presents the design, application, and testing of an alternative communication system based on Brain Computer Interface (BCI). The prototype includes six LEDs flickering at different frequencies, and each LED corresponds to one command. Depending on the direction of the gaze of the subject, the neuronal activity pattern in their occipital lobe will be consistent with the targeted LED flickering rate. By recording the electroencephalogram (EEG), and determining the neuronal firing frequency, the system uses Steady State Visual Evoked Potentials (SSVEPs) to convey one of six commands to caregivers. The SSVEP-based system uses an OpenBCI Ganglion 4-channel biosensing board to acquire brain signals and Arduino Uno for system control. Based on preliminary testing on eleven subjects, the overall accuracy of the system was 89%. Accuracy is the percentage at which the system correctly recognized and sent the selected command.