Functional dissection of auditory cortex with magnetic resonance imaging

Abstract The purpose of this article is to discuss the impact of the newest neuroimaging techniques on knowledge regarding the functional organization of the auditory system. An impressive acceleration of comprehension of this subject has been realized following the introduction of functional magnetic resonance imaging (fMRI) methods into audiological research and, even more, by the creation of tailored procedures able to extract from the brain information regarding the processing of auditory stimuli. Until very recently, the study of the auditory system has proceeded at a considerably slower pace than other functional systems. This is due to several problematic factors, including the intrinsic anatomy of the auditory system and some peculiar interactions between audition mechanisms and fMRI techniques. To overcome these problems, different approaches have recently been proposed, which generally require a careful tailoring of the experimental designs of fMRI methodology, and of the strategies of data processing, to the specific problems of audition and the particular research goal. This article reviews the present state of fMRI research on audition, examining the solutions already existing and those under development in relation to the specific problems of auditory fMRI. The increasing knowledge about the auditory system, derived in part from fMRI research, has already opened new avenues in the comprehension of basic and high level neural processes in audition.