Figure 3.

Group-level average of the beat- and meter-related steady-state EPs elicited by the 2.4 Hz auditory beat in the control condition (top), the binary meter imagery condition (middle), and the ternary meter imagery condition (bottom). The frequency spectra represent the amplitude of the EEG signal (in microvolts) as a function of frequency, averaged across all scalp electrodes, after applying the noise subtraction procedure (see Materials and Methods). The group-level average frequency spectra are shown using a thick colored line, while single-subject spectra are shown in gray lines. Note that in all three conditions, the auditory stimulus elicited a clear beat-related steady-state EP at f = 2.4 Hz. Also, note the emergence of a meter-related steady-state EP at 1.2 Hz in the binary meter imagery condition, and at 0.8 and 1.6 Hz in the ternary meter imagery condition.