CONSTRUCTION OF A MORPHOLOGICAL FILTER FOR DETECTING AN EVENT-RELATEDPOTENTIAL P300 IN SINGLE SWEEP EEG RECORD IN CHILDREN

A morphological filter for single sweep records of event-related poten tial (ERP) obtained in an auditory oddball paradigm, especially P300 w aveform, was constructed. By combining four basic operations; erosion, dilation, opening and closing, we could derive a desired filter whose properties fit the current objectives. The morphological filter for t he single sweep records of ERP was constructed by taking into account the features of the signal and noise components. The morphological fil ter had superior properties for distinguishing the signal from the noi se even when both were within the same frequency band, as in case of c hildren. The constructed morphological filter was evaluated by using t he simulation data of ERP and then applied to the actual ERP data obta ined from nine normal children. The constructed morphological filter w as proved to be an appropriate tool for single sweep analysis of ERP.