ABSTRACT
In order to analyze the relation between EEG and evoked potentials (EPs), we studied frontal visual EPs (VEPs) by means of a recently introduced algorithm for selective averaging. This algorithm is based on the inverse relationship between amplitudes of alpha or theta components of the spontaneous EEG activity and EP amplitudes. Stimuli were only applied if the root mean square (RMS) value of the ongoing EEG at the lead F4 was below an individual threshold level (“selective stimulation”). For this comparison, the EEG was filtered in one of the frequency ranges “alpha”, “theta” and “alpha & theta”, respectively.
