Network mechanisms underlying the role of oscillations in cognitive tasks
Fig 1
Frequency response of a network of QIF neurons.
Here we show the response of an excitatory network of 104 all-to-all coupled QIF neurons with distributed input currents to periodic forcing. The model parameters are chosen such that the network is bistable, see also Fig 2A. Each panel shows the network-averaged firing rate (black: network of QIF neurons; orange: result of mean-field equations Eq 1) and raster plot of the response for an initial condition in the low-activity state (top, r ≈ 6Hz) and high-activity state (bottom, r ≈ 73Hz), as well as the oscillatory forcing I(t). A At low enough frequencies, the system is pushed from the low- to the high-activity state. B At slightly higher frequencies, both states persist under the forcing. C Driven with forcing from an intermediate range of frequencies, the state with high firing activity destabilizes in favor of the state with low firing activity. D At high frequencies, both states persist under the forcing. Parameters: τ = 20ms, η = −10, Δ = 2, , A = 1.