Extended Data Fig. 1: Linear kernels extracted from all ground truth datasets.

The kernels are optimized such that when the ground truth spike times are linearly convolved with the kernel, the experimentally recorded ΔF/F trace is ideally approximated. In practice, this is achieved using regularized linear deconvolution of calcium traces based on spike times (Methods). Kernels vary both in amplitude and shape across datasets and within datasets. For single neurons, the kernel area (right panels) is only shown if the kernel could be reliably determined, as tested with the variability of the kernel across the recording (Methods). The red arrow in panel (r) indicates an outlier case that is discussed in Extended Data Fig. 4a. m: Mouse, zf: Zebrafish.