The modulatory effect of asynchronous release dynamics on synaptic information efficacy during short-term depression.

(A) Relative difference between the mutual information rates of the release site with and without depression, as a function of depression multiplier, d, and release probability, q0, of asynchronous release. For the synchronous spike-evoked release, the dynamics is kept fixed at c = 0.5 and p0 = 0.7. The black line shows the boundary between positive and negative values. (B) Relative difference between the energy-normalized information rates of the release site with and without depression. (C) Three functional categories of the release site during depression. (D) Changes in the mutual information rate (solid lines), R0−RD, and energy-normalized information rate (dashed lines), , during depression. The functions are plotted against asynchronous release probability, q0, for different values of depression multiplier, d. (E) The impact of similar depression dynamics for asynchronous and synchronous spike-evoked release (c = d) on the rate changes during depression. We simulate R0 − RD and as a function of input spike rate, α, for different values of depression multiplier. For the simulations in this figure, the recovery time constants are fixed at e = f = 0.1.