Fig. 2: Spatiotemporal mapping of MIM-activated cortical neurons in vivo.

a Upper: cartoon showing the general scheme for the in vivo two-photon imaging experiments. Lower: cartoon showing the configuration of the MIR fiber tip, the two-photon imaging objective, and the Ca²⁺ dye loading micropipette. ACSF: artificial cerebrospinal fluid. b An example in vivo two-photon image (averaged 100 frames). The red arrow and the dashed circle indicate the neuron for which Ca²⁺ activity traces are shown in the next panel. c Ca²⁺ activity traces of an example neuron (marked in b) in six consecutive trials. The two red dashed lines indicate the start and the end of the MIM application. d A reconstructed 3D map showing the positions of all MIM-activated neurons (red balls) and unaffected neurons (gray balls) in the imaged volume, consisting of eight focal planes from one example mouse. e Upper: a pseudo-colored plot summarizing the trial-integrated Ca²⁺ activity trace for each neuron identified as MIM-activated. Neurons were sorted by their relative increment of activity level (from pre-MIM to MIM). Lower: a grand average of the Ca²⁺ activity traces for all 167 MIM-activated neurons.