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PubMed · 15974474

Integrated study of topographical functional maps based on an auditory comprehension paradigm using an eigensystem study and spectrum analysis.

Mercedes Cabrerizo·Malek Adjouadi·Melvin Ayala·Ilker Yayali·Prasanna Jayakar·Gustavo Rey
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Abstract

This study integrates a spectral analysis of key frequency bands (Alpha, Beta, Delta, and Theta) with an eigensystem-based study in order to validate brain functional mappings associated with the characterization effects of an Auditory/Comprehension paradigm. This numerical characterization supported by topographic functional maps brings added insight in the involvement of the Wernicke and Broca's brain areas to language comprehension. A thorough examination of EEG recordings through the eigensystem reveals that eigenvectors associated with the largest eigenvalues produce an interesting activity pattern located in the frontal area of the brain directly attributable to those characteristic behaviors found in the Alpha, Beta, Delta, and Theta frequency bands. An evaluation of spectral arrays is performed using topographic maps of the induced brain activities during both listening and answering phases. This evaluation is then augmented with quantifying measures using the eigensystem study while results are validated through integration of EEG activity and eigensystem modalities. Such a representation can provide insightful information on how different patients react during an auditory and response phases, and in the ability to detect the presence of potential neurological disorders by assessing similar/dissimilar behaviors with respects to all former patients already included in the database. The algorithm as developed in this study could be extended in its application to other brain functional mapping tasks given its simple but effective practical mathematical foundation.

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Acoustic StimulationAdultAlgorithmsAuditory CortexBrain MappingComprehensionElectrodesElectroencephalographyEvoked Potentials, AuditoryFemaleFunctional LateralityHumansLanguageMalePrincipal Component AnalysisSensitivity and SpecificitySignal Processing, Computer-AssistedSpectrum AnalysisComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Mercedes Cabrerizo, Malek Adjouadi, Melvin Ayala, Ilker Yayali, Prasanna Jayakar, Gustavo Rey. 2005. Integrated study of topographical functional maps based on an auditory comprehension paradigm using an eigensystem study and spectrum analysis.. https://doi.org/10.1007/s10548-005-4448-3

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