Multiparametric corticofugal modulation and plasticity in the auditory system

The auditory systems of adult animals can be reorganized by auditory experience. The auditory cortex, the corticofugal system and the cholinergic basal forebrain are crucial for this reorganization. The auditory system can undergo two different forms of reorganization-expansion and compression. Whereas expanded reorganization has been found in different species and different sensory systems, compressed reorganization has only been found in the auditory system of the moustached bat, which is highly specialized for echolocation. Here, we review recent progress in our understanding of the corticofugal system and the reorganization of the auditory system.