Stochastic neural field model of stimulus-dependent variability in cortical neurons
Fig 4
(a) Plot of normalized variance var(U)/A2 for U = A cos(θ) as a function of θ for a single ring network and various κ. In the spontaneous case (κ = 0) the variance is uniformly distributed around the ring (ignoring transients). The presence of a stimulus (κ > 0) suppresses the overall level of noise and the variance exhibits a bimodal tuning curve. (b) Plot of variance in firing rates var(f(U) (in units of ) as a function of θ for a single ring network and various κ. f is given by the sigmoid function (2) with γ = 4 and η = 0.5. The corresponding amplitude A ≈ 1.85.