Skip to main content
. Author manuscript; available in PMC: 2014 Jul 10.
Published in final edited form as: Neuron. 2013 Jul 10;79(1):141–152. doi: 10.1016/j.neuron.2013.04.038

Figure 8. Simulating a functional circuit for sparse and background-invariant coding.

Figure 8

(A) Functional circuit in which a primary AC neuron provides excitation to both BS and NS neurons in the higher-level AC. The NS neuron provides delayed and sustained inhibition onto the BS neuron. The auto-synapse onto the NS neuron represents any of a number of cellular or circuit mechanisms that could produce sustained firing that outlasts synaptic input to a neuron. Inset schematizes the change in spiking probability of BS neuron in response to a short burst of primary AC input. (B) Simulations of this circuit with primary AC responses to four different songs as input (continuous traces). Black ticks show spiking of a simulated BS neuron. (C) Simulations of this circuit with primary AC responses to auditory scenes as input (left). Average response of BS neuron to primary AC input is shown on right. Scale bars show firing rate (Hz). (D) Extraction index measured from the auditory scene responses of simulated primary AC (n = 70, orange) and higher-level AC BS neurons (n = 70, blue). Solid lines show mean and shaded areas show +/−SEM. Asterisks indicate SNRs at which the two populations are significantly different (p < 0.05, Wilcoxon). See also Figure S7.