MULTICHANNEL PC-BASED DATA-ACQUISITION SYSTEM FOR HIGH-RESOLUTION EEG

This paper describes a complete, high-performance data-acquisition sys tem for high-resolution EEG, The system includes preamplified EEG elec trodes, rigid helmets, differential instrumentation and software-contr olled gain amplifiers, digitizing and control circuitry, and optical c oupling to a 486 PC, Miniaturized preamplifiers mounted on individual electrodes reduce coupling to external electromagnetic fields and mini mize signal distortion caused by increased and/or imbalanced electrode impedances, Electrodes are applied quickly and with minimal skin prep aration, yet with high packing densities and repositioning consistent to about 1-3 mm in repeated applications. Extensive testing under real istic conditions demonstrates that the system provides superior electr ical performance compared to currently available commercial systems.