Before revision:  Using a biologically plausible model based on recurrent networks of excitatory and inhibitory neurons arranged in cluster, we classify the effects of cell-type specific perturbations on the circuit 's stimulus-processing capability. We found that perturbations differentially controlled processing speed, leading to counterintuitive effects such as improved performance with increased input variance.
After revision:  Our theory demonstrates that perturbation effects on stimulus processing can be predicted by intrinsic gain modulation, which controls the timescale of the circuit dynamics. Our theory leads to counter-intuitive effects such as improved performance with increased input variance.