To investigate whether this is a general fact for all region-specific laminar HRFs, we performed similar analyses for all other 66 regions and summarized the results in Fig. 6. 66 out of 68 regions had significant difference (p < 0.05 corrected) across the layers for the response height, 62 out of 68 regions for time to peak, and 36 regions for FWHM. In summary, the HRF varies across cortical layers in many brain regions and it is necessary to recover the latent neural signal at each layer before performing connectivity analysis.
