Responses of neuronal ensembles to mean-driven, fluctuation-driven and synchrony-driven rate-code inputs

Equations of motion for mean firing rate, fluctuation and synchrony have been derived with the use of the augmented moment method (AMM) for the generalized rate-code model including additive and multiplicative noise (H. Hasegawa, Phys. Rev. E 75, 051904 (2007)). We have investigated the response of a neuronal ensemble to three kinds of inputs: mean-driven, fluctuation-driven and synchrony-driven inputs. It has been shown from the independent component analysis (ICA) of our results, that mean firing rate, fluctuation (or variability) and synchrony may carry independent information in the population rate-code model. The input-output relation of mean firing rates is shown to have higher sensitivity for larger multiplicative noise, as recently observed in prefrontal cortex. The results calculated by the AMM are in good agreement with those by direct simulations. A comparison is made between results obtained by the spiking integrate-and-fire (IF) model and our rate-code model. PACS No. 87.10.+e, 84.35.+i Electronic address: [email protected]