Fig. 7.

Information-limiting noise correlations account for realistic psychophysical thresholds. A population of independent Poisson neurons (red line) roughly the size of the V1 pool that can be used downstream for discrimination in typical psychophysics experiments (black arrow; see text for estimation) leads to psychophysical thresholds that are orders of magnitude smaller than human performance (green arrow). A population with information-limiting correlations of 0.12 on average (black line) accounts for realistic thresholds. Simulations are based on a simplified model with synthetic covariance and tuning curves, with average amplitude of 20 spikes per second (SI Appendix, Table S5).