Spectral processing in the inferior colliculus

The central nucleus of the inferior colliculus (ICC) receives direct inputs from all of the major auditory nuclei in the brainstem and, in turn, provides nearly an of the input to the auditory forebrain. The manner in which the brainstem projections to the ICC combine creates functonally distinct synaptic domains within the ICC and presumably basic differences in the spectral sensitivity of ICC neurons. In this chapter, the anatomy of the mammalian ICC is reviewed. Then, the frequency response areas of ICC units are described, followed by a review of what is known about the roles of the various excitatory and inhibitory inputs to the ICC in shaping these response areas. Finally, the functional roles of the ICC in the processing of spectral information are discussed.