Fig. 3.

Effect of firing rate on noise correlations. A: distribution of noise correlations for 3 ranges of joint firing rate. B: average noise correlations grow with joint firing rate. C: dependence of noise correlations on the firing rate of each neuron in the pair. The average over all pairs is shown. D: taking the geometric mean of the pair's firing rates and fitting an exponential form provides a reasonable approximation. The dependence of noise correlations on firing rate can therefore be reduced to a 1-dimensional function. Note that axes are log scaled. E–H: noise correlations as a function of timescale and joint firing rate in each stimulus condition.