Central dysmyelination reduces the temporal fidelity of synaptic transmission and the reliability of postsynaptic firing during high-frequency stimulation.

Auditory brain stem circuits rely on fast, precise, and reliable neurotransmission to process auditory information. To determine the fundamental role of myelination in auditory brain stem function, we examined the evoked auditory brain stem response (ABR) from the Long Evans shaker (LES) rat, which lacks myelin due to a genetic deletion of myelin basic protein. In control rats, the ABR evoked by a click consisted of five well-defined waves (denoted waves I-V).