1. Dependence of the STN–GPe subcircuit behavior on the interconnection efficacies between the STN and GPe and the background inputs.
Dependence of the STN–GPe subcircuit behavior on the interconnection efficacies between the STN and GPe and the background inputs. A, Population oscillation frequency, mean neuronal firing rate, and CV for activity of STN neurons (left column) and GPe neurons (right column) as a function of interconnection strengths gGPe–STN and gSTN−GPeNMDA. Beta-band oscillations are robust over a broad parameter regime. B, Oscillation frequency, firing rate, and CV of STN neurons (left column) and GPe neurons (right column) as a function of the strength of inhibitory background input to GPe neurons (gGPeb) and excitatory background input to STN neurons (gSTNb). In an intermediate range of gGPeb values, CV is large (>0.5; bottom) and the oscillation frequency is in the beta range (∼8–20 Hz; top) for a wide range of gGPeb values. Note that for the yellow regime in the top panels in A, and the red regime in the top panels in B, the CV is very low, and hence we do not consider these as representative of parkinsonian conditions. In determining the population oscillation frequency, we use the autocorrelation function of the population firing rate to estimate the oscillation period T, and the corresponding frequency is given by 1/T.
Wei Wei et al. J. Neurosci. 2015;35:
©2015 by Society for Neuroscience