Figure 3: Exploration of the parameter space of the encoding readout model.

Data are simulated with the encoding-readout model with N=20 neurons in each pool. Panels represent the mean over 100 simulations with 300,000 trials each.

a, Difference in the accuracy of a linear decoder of stimulus applied to correlated and shuffled simulated neural activity for different values of the signal-noise angle (γ) and population-wise correlations (ν). For all panels, black solid line: boundary between a regime with information-limiting correlations and information-enhancing correlations. b, The difference between correlated and shuffled activity in the fraction of trials in which the two neural features encode consistent stimulus information is higher in the information-limiting regime and increases with the population-wise correlations strength.

Panels c-e refer to the consistency-independent readout. c-d, Difference in average pairwise correlations (c) and population-wise correlations (d) between trials with correct and incorrect predicted task performance for different combinations of model parameters. e, Difference in task performance predicted by applying the consistency-independent readout to correlated and shuffled simulated neural activity for different combinations of model parameters. For panels c-i, dashed black line: boundary between a regime where task performance is higher for correlated responses and a regime where performance is higher for shuffled responses. The overlap between the continuous and dashed black line indicates that information-limiting correlations are also detrimental for behavior.

Panel f-h refer to the enhanced-by-consistency readout (consistency modulation index η = 0.85). f-g, Same as in c-d. With the enhanced-by-consistency readout correlations are higher in correct trials. h, Same as in e. The area between the dashed and the continuous black lines indicates a regime where correlations are information-limiting but task performance is higher for correlated responses. In the parameter range between the two lines, this readout can overcome the negative impact of correlations. Dark and light gray dots and ellipses: mean values and range between the 25^th and the 75^th percentile of the signal-noise angles and population-wise correlations for PPC data from the sound localization task and evidence accumulation task, respectively.

i, Difference in task performance predicted by applying the enhanced-by-consistency readout or the consistency-independent readout (with matched readout efficacy) for different combinations of model parameters.