Modeling amplitude-modulated (AM) tone encoding behavior of cochlear nucleus neurons

An attempt was made to understand the mechanisms underlying the response of the cochlear nucleus (CN) neurons, specifically the choppers, to the AM tone. The AM tone excitation via the auditory nerve fibers was modeled as a combination of DC, AC, and a zero-mean Gaussian noise current at the soma of the model neuron. The DC represents the high frequency carrier beyond the neuron´s phase-locking limit and the AC represents the envelope. With a systematic variation of DC, AC, and noise amplitudes, the stellate cell models could reproduce the low-pass and band-pass modulation transfer functions (MTFs) and intrinsic oscillations (IOs). A close correlation was observed between the IO frequency and the best envelope frequency in the stellate cell models