Figure 1. Brain-wide functional connectivity across spatial scales.
(A) Functional connectivity can be measured at the macro-, meso- and microscale resolution. Colored traces (lower row) illustrate time-series of brain activity recorded in two distant locations i and j. Functional connectivity cij is the correlation coefficient between these time-series. The correlation values typically increase with spatial scale. 2p imaging: two-photon optical imaging. See Box 1 for an explanation of the methods. (B) The diversity and specificity in responses and connectivity of different cell types can contribute to macroscale functional connectivity.