Extended Data Fig. 4: Two-photon photostimulation and volumetric imaging protocol.
From: Connectivity underlying motor cortex activity during goal-directed behaviour
a, Left, Schematics of two-photon photostimulation of targeted neurons (magenta) and measurement of evoked responses in non-stimulated neurons (green) using volumetric calcium imaging. Right, example imaged volume of layer 2/3, motor cortex, with two photostimulation targets indicated (magenta). Both photostimulated target neurons and imaged neurons were excitatory cells. b, Schematics of photostimulation timing during volumetric imaging shown for two consecutive photostimulation trials. Target cells were photostimulated in the superficial plane (‘plane 1’). Imaging each plane lasted 33 ms, followed by a 15 ms gap without imaging. Four spiral photostimulations (each spiral lasting for 3 ms, see inset) occurred in the gap between each imaged plane (Methods).
