EEG-based Brain-to-computer Communication: System Description

This paper describes an adaptive decoding device designed to develop and evaluate EEG-based communication from the device user to a computer. The decoder transforms EEG activity into cursor movement. The operator, who is considered part of the device, defines the parameters governing this transformation and makes adjustments periodically as the user’s control of the EEG changes. The user watches a video terminal that displays the cursor and the stationary target. The resulting device-user interaction forms a complex dual control structure in which both elements (the device and the user) adapt to achieve the ultimate mutual goal of fast, accurate control of cursor movement. The hardware components are a Grass model 8 EEG polygraph, a Texas Instruments TMS320C25 based signal processing board, and an Intel 80286 based IBM PC/AT computer. This combination of the high speed TI processor with the AT host processor supports the custom software that will ultimately allow the adaptive device to be operator free. The paper presents results illustrating successful EEG-based cursor control with this system.