New approach to localize speech relevant brain areas and hemispheric dominance using spatially filtered magnetoencephalography
- 4 October 2001
- journal article
- research article
- Published by Wiley in Human Brain Mapping
- Vol. 14 (4), 236-250
- https://doi.org/10.1002/hbm.1056
Abstract
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.Keywords
Funding Information
- Johannes and Frieda Marohn Foundation (Erlangen, Germany)
This publication has 56 references indexed in Scilit:
- Accuracy and Limitation of Functional Magnetic Resonance Imaging for Identification of the Central Sulcus: Comparison with Magnetoencephalography in Patients with Brain TumorsNeuroImage, 1999
- Functional neuronavigation with magnetoencephalography: outcome in 50 patients with lesions around the motor cortexJournal of Neurosurgery, 1999
- Integration of Functional Magnetic Resonance Imaging Supported by Magnetoencephalography in Functional NeuronavigationNeurosurgery, 1999
- Atypical temporal lobe language representationNeuroReport, 1999
- Anatomical Congruence of Metabolic and Electromagnetic Activation Signals during a Self-Paced Motor Task: A Combined PET–MEG StudyNeuroImage, 1998
- Magnetoencephalographic study on the cerebral neural activities related to the processing of visually presented charactersCognitive Brain Research, 1996
- Neural correlates of category-specific knowledgeNature, 1996
- Comparison of magnetic, and metabolic brain activity during a verb generation taskNeuroReport, 1994
- Topographic mapping of the pattern onset evoked magnetic response to stimulation of different portions of the visual fieldInternational Journal of Psychophysiology, 1994
- Sensory Speech Area Investigated by MagnetoencephalographyBiomedizinische Technik/Biomedical Engineering, 1994