Interspike interval correlations in neuron models with adaptation and correlated noise
Fig 5
Pattern of interval correlations for the adaptive GIF model.
The PRC Z(τ) and SCC ρk for three different cases that corresponds to ν < 0 A, 0 < ν < 1 B and ν > 1 C are shown. The first two cases A, B resemble the previously discussed cases of the adaptive LIF model, see Fig 4. For the third case C both adaptation and correlated noise can have counter intuitive effects on the SCC if they act mainly on the proportion of the ISI where the PRC is negative. This can be ensured by appropriate choice of the time scales, here τa ≈ T*/2 and τη ≈ T*/2. Thus the adaptation can give rise to positive interval correlations and additional colored noise with varying correlation time initially decreases the SCCs for intermediate τη and eventually leads to enhanced positive correlations for large τη. Parameters (A, B, C): γ = (1, 1, −1), μ = (10, 20, 1), βw = (3, 1.5, 5), τw = (1.5, 1.5, 1.1), τa = (10, 10, 1), Δ = (10, 10, 2.3), σ2 = 10−3, D = 0 and resulting T* = (1.24, 0.57, 1.91).