An example of the synchronisation of infra-slow oscillations of pupil areas observed simultaneously in both eyes.

<p>C: graph showing overlaid oscillations simultaneously observed in the pupil area of the left (red line) and right (blue line) eyes. A and B: graphs showing the magnified fragments of the recording shown in graph C. D and E: colour surface plots showing the cross-correlograms calculated with a sliding window (step, 10 s; width, 300 s) for two fragments of the recording shown in graph C. The y-axis denotes the time lag of the correlation function; the x-axis denotes the time range; and the cross-correlation value is coded by colour (colour scale is given on the inset). F and G: time-averaged cross-correlograms computed from D and E, respectively; the SDs of the calculated means are shown in violet. Note that the pupil area oscillations are synchronised between the eyes during ECoG activation (A, D, F) and deactivation (B, E, G).