Magnetoencephalography in the Study of Cortical Auditory Processing

摘要

This thesis deals with the auditory system of the human brain. Seven publicationspresenting magnetoencephalographic (MEG) results on the functional organization of the auditory cortex and source modelling of MEG data are presented. The data, displaying brain structures which are organized according to stimulus features and related to the detection and short-term memory responses of the auditory system, were mostly gathered using the Neuromag-122 whole-head magnetometer. New methods to whole-head MEG data analysis were reported in order to utilize the data obtained with the magnetometer. The experimental paradigms in the publications of this thesis dealt with the tonotopic and ampliotopic organization of the auditory cortex, processing of simple and complex sounds, and auditory memory. The data was analyzed using dipole models, minimum-norm estimation and signal-space projection method.