Extended Data Fig. 6: Single-trial side-by-side comparisons between phase fields under different stages of filtering and flattening procedures.
a, the simultaneous snapshots showing phase fields in the spatially filtered (left) and unfiltered fMRI slow fluctuations (middle), as well as original (demeaned) fMRI signals (right) across the inflated left cortex (lateral view). The white circles (A and B) mark the surface locations of sample spirals highlighted in panel c, d and e. The circular colormap represents the phase. b, same as a, but with a medial view. c, Same as a and b, but over the flattened cortical surface. The black squares with dashed lines mark the regions shown in d and e. The white circles mark the sample spirals highlighted in d and e. d, The zoomed-in time-lapse snapshots of the sample spirals highlighted by the white circles in c (marked by the black square on the left). Each column shows the phase field of the same region in either spatiotemporal bandpass filtered (left), temporal bandpass filtered (middle) or raw (original, demeaned, right) fMRI signals. Each row shows the temporal evolution of the corresponding phase fields. The white arrows highlight the rotational direction of the sample spirals. The black arrows mark the time step around which the full brain snapshots in a, b and c were captured. e, Same as d, but within a different cortical region highlighted in c (marked by the black square on the right).
