Fibers of the auditory nerve enter the cochlear nucleus (CN) innervating three major subdivisions: the anteroventral cochlear nucleus (AVCN), the posteroventral cochlear nucleus (PVCN), and the dorsal cochlear nucleus (DCN). Of the major pathways leaving the cochlear nucleus, one projects ultimately to the inferior colliculus (IC) through the lateral lemniscus (LL); The other projects to the superior olivary complex (SOC) which plays an important role in sound localization. Biophysical and signal processing models of all these structures are proposed in the following.