Fig. S6.

The correspondence between neural activity and hemodynamics at <0.4 Hz in awake mouse brain. Time courses from regions R1 (A) and R2 (B) are the same region as shown in Fig. 3A. Changes in corrected Thy1-GCaMP6f fluorescence and Δ[HbT] are plotted as unfiltered (top row), 0.4-Hz low-pass filtered (middle row), and 0.4-Hz low-pass filtered, and temporally shifted by 1.14 s (bottom row). (C) The corresponding time series of images from 5 to 17.5 s of neural activity and hemodynamic after <0.4-Hz filtering (shown in 1.14-s steps, corresponding to the phase lag found between neural and hemodynamics of this trial). Patterns of integrated neural activity closely match subsequent patterns of hemodynamics seen in the following panel. The <0.4-Hz frequency band was chosen based on frequency-dependent cross-correlation analysis shown in Fig. 4. This result demonstrates that, independent of linear model-based fitting, the low-frequency enveloping of neural activity shows strong spatiotemporal correlations with hemodynamics at low frequencies. The clear temporal delay between neural and hemodynamic signals rules out the possibility that this effect results from hemodynamic cross talk. This data are also shown in Movies S4 and S5 with Movie S6 showing the deconvolution-based fit initialized using <0.4-Hz filtered data.