Fig. 2

Fig. 2

Main steps of experimental data elaboration. Every layer of the imaged 3D zebrafish brain is spatially downsampled, as shown in panel a in order to obtain signals from pixel ensembles of size comparable to a neuron (2 × 2 pixels). b Detrending for slow oscillations by subtraction of moving average. c Results of neurons selection for one of the layers: (i) raw data, (ii) selection of pixels with maximum value above a fixed threshold, and (iii) only pixels with skeweness larger than 0.4. At the end of the neurons selection procedure the number of identified neurons in the whole brain is about 5 ⋅ 10⁴. d Procedure to obtain the experimental raster plot starting from calcium fluorescence time series of the selected neurons. A spike is identified by its upwards threshold crossing time