Functional Connectivity and Tuning Curves in Populations of Simultaneously Recorded Neurons
A) Mean spike prediction accuracy under the tuning curve (black), coupling (blue), and full (red) models. Where spike prediction accuracy denotes the cross-validated log likelihood ratio relative to a homogeneous Poisson process reported in bits/s. Error bars denote SEM across neurons (tuning curve models) or networks (coupling and full models). In all cortical areas the coupling model out-performs tuning curve models once coupling between 10–30 neurons is included. Note that for spontaneous activity in V1, coupling improves spike prediction accuracy even though stimuli were not displayed and tuning curves cannot be fit. B) Mean decoding accuracy under the tuning curve (black) and full (red) models, as well as accuracy for simulated, conditionally independent neurons with data-matched tuning curves (green). Note that the full model slightly outperforms the tuning curve model alone, but dependencies between neurons degrade decoding performance relative to the simulated conditionally independent neurons. Error bars denote standard deviation across neurons (tuning curve models) or networks (full model).