AN INTEGRATED SYSTEM TO TRIGGER FEEDBACK-COUPLED EVENT RELATED BRAIN POTENTIALS

INTRODUCTION Long going physiological research [1], strongly suggests that the macroscopic electric (i.e. EEG) state of a subject's brain influences the responses to defined stimuli, manifested in evoked (or event-related) potentials. Since this evidence is up till now based on post-hoc evaluation of EEG data, we designed and built a data acquisition system able to fully digitally record raw EEG signals from up to 32 scalp electrodes in standard configuration over a prolonged period of time. The design was furthermore meant to evaluate the incoming signals according to user defined criteria and in succession trigger the stimulus to evoke an ERP by either of auditory, visual or sensory stimuli [4]. All these requirements have to be satisfied within the space and financial constraints given by off-the-shelve PC technology.