Figure 3

Quadrupolar response of the periodic pattern to electric fields. When the signal is switched from SL to SH (top), no change was observed in the periodic pattern of the cell (bottom). τ=45 ms (fτ=22 Hz), τL=2.2 ms (fτL=458 Hz), and τH=0.27 ms (fτH=3.7 kHz). This indicates that the periodic pattern is not related to ionic action under the application of electric fields.