[An analysis of evoked brain activity by computing the average duration of the wave half-period].

Poststimulus spectral EEG changes and their relation to averaged evoked potential (AEP) were analysed using average wave half period length (AWHL) computation method. In 5 healthy subjects increase of AWHL in the latency range of slow AEP components was revealed during simple motor reaction to visual stimuli. It was shown that AWHL increase could not be explained by AEP contribution to single realizations and/or by the process of suppression of EEG rhythms.