title: The role of inhibition in a computational model of an auditory cortical neuron during the encoding of temporal information.
abstract: In auditory cortex, temporal information within a sound is represented by two complementary neural codes: a temporal representation based on stimulus-locked firing and a rate representation, where discharge rate co-varies with the timing between acoustic events but lacks a stimulus-synchronized response. Using a computational neuronal model, we find that stimulus-locked responses are generated when sound-evoked excitation is combined with strong, delayed inhibition. In contrast to this, a non-synchronized rate representation is generated when the net excitation evoked by the sound is weak, which occurs when excitation is coincident and balanced with inhibition. Using single-unit recordings from awake marmosets (Callithrix jacchus), we validate several model predictions, including differences in the temporal fidelity, discharge rates and temporal dynamics of stimulus-evoked responses between neurons with rate and temporal representations. Together these data suggest that feedforward inhibition provides a parsimonious explanation of the neural coding dichotomy observed in auditory cortex.
authors: Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, London, United Kingdom.
authors: Daniel
authors: D
authors: Bendor
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D002144:Callithrix; D019295:Computational Biology; D003198:Computer Simulation; D009474:Neurons / Q000502:physiology*; D013997:Time Factors