Mean amplitudes of standard- and deviant-waves for each condition and scalp position (Experiment 1).

<p><i>Note</i>. Mean amplitudes (µV) are indicated with <i>SE</i> values in parentheses. S: values for standard stimuli; D: values for deviant stimuli; Subscript indicates tone frequency in Hz; number of epochs (n) are indicated in parentheses. The time windows adopted are 59–109 ms for monkey A and 61–111 ms for monkey Y (See Methods).