Open AccessNew approach to localize speech relevant brain areas and hemispheric dominance using spatially filtered magnetoencephalography
Author(s) -
Kober Helmut,
Möller Martin,
Nimsky Christopher,
Vieth Jürgen,
Fahlbusch Rudolf,
Ganslandt Oliver
Publication year - 2001
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.1056
Subject(s) - magnetoencephalography , laterality , psychology , lateralization of brain function , broca's area , neuroscience , superior temporal gyrus , inferior frontal gyrus , middle temporal gyrus , audiology , functional magnetic resonance imaging , electroencephalography , medicine
We used a current localization by spatial filtering‐technique to determine primary language areas with magnetoencephalography (MEG) using a silent reading and a silent naming task. In all cases we could localize the sensory speech area (Wernicke) in the posterior part of the left superior temporal gyrus (Brodmann area 22) and the motor speech area (Broca) in the left inferior frontal gyrus (Brodmann area 44). Left hemispheric speech dominance was determined in all cases by a laterality index comparing the current source strength of the activated left side speech areas to their right side homologous. In 12 cases we found early Wernicke and later Broca activation corresponding to the Wernicke‐Geschwind model. In three cases, however, we also found early Broca activation indicating that speech‐related brain areas need not necessarily be activated sequentially but can also be activated simultaneously. Magnetoencephalography can be a potent tool for functional mapping of speech‐related brain areas in individuals, investigating the time‐course of brain activation, and identifying the speech dominant hemisphere. This may have implications for presurgical planning in epilepsy and brain tumor patients. Hum. Brain Mapping 14:236–250, 2001. © 2001 Wiley‐Liss, Inc.