Fig. 7.

The average empirical rat cortical HRF derived from fiber-photometry GCaMP6f and Rhodamine B signal in rat S1, PrL, ACC, RSC, and AI is significantly faster and narrower than the canonical HRF. (a) The average empirical rat cortical HRF (blue solid line, the shaded area represents standard error) obtained from 44 total photometry recordings versus the canonical HRF (black dash line). The average empirical rat cortical HRF was pooled from HRFs in S1: $n=4/2$ repetitions, PrL/ACC/RSC/AI: $n=10/2$ repetitions. In addition to the S1 HRF, the HRFs of PrL, ACC, RSC, and AI were computed from the same group of animals using a four-channel recording system. The intraindividual HRFs were first averaged, then these average individual HRFs were used to calculate the average empirical rat cortical HRF. (b) The difference in shape between the empirical HRFs for individual cortical areas (colored solid lines) appears to be substantially smaller than between each HRF and the canonical HRF (black dashed line). (c) The time-to-peak latencies of the empirical HRFs are significantly shorter than the canonical HRF ($p<0.001$). (d) The FWHMs of the empirical HRFs are significantly narrower than the canonical HRF ($p<0.001$).