For the analysis of repetition effects individual trials were averaged
according to their position in the trains. Therefore, trials presented in
the same position but belonging to trains of different length were
averaged together. Only stimuli in positions 3rd to 24th were analyzed
to assess repetition effects. The first tone in each train (deviant) and
the second tone (first repetition) were excluded from the analyses of
repetition effects, in order to avoid residual effects from the preceding
deviant, or “after deviant” effects