I haven't seen anyone recommend this book yet on this
thread:
Aitkin, Lindsay. The auditory cortex : structural and functional
bases of auditory perception / Lindsay Aitkin. 1st ed. London
; New York : Chapman and Hall, 1990.
Well written, and it certainly drives home how little we
really know about auditory cortex (and the wulst (sp?) in avians)
outside of specially-adapted species like bats and barn owls.