Extended Data Fig. 9: Eigenspectrum of electrophysiologically recorded data.
From: High-dimensional geometry of population responses in visual cortex
We recorded neural activity electrophysiologically in response to 700 out of the 2,800 stimuli, and concatenated the recordings, resulting in a total of 877 neurons recorded across 6 experiments. a, With this smaller number of stimuli and neurons, convergence to a power law is not complete, and the exponent cannot be estimated accurately (compare with Fig. 2g–j). We therefore compared the electrophysiology data to the responses generated by these stimuli in 877 neurons sampled randomly from either a single two-photon imaging experiment (dark blue) or all experiments combined (light blue). The red and pink colours show electrophysiology eigenspectra with time bins of 50 ms or 500 ms; the red line shows the best linear fit to estimate the exponent. b, The blue curves represent power-law exponents estimated from the responses of different-sized neuronal subpopulations to this set of 700 stimuli; the shading represents s.e.m. over different random subsets of neurons. The red and pink crosses denote estimated exponents from electrophysiology data for 50-ms and 500-ms bin sizes.
