title: Cortical distribution of speech and language errors investigated by visual object naming and navigated transcranial magnetic stimulation.
abstract: Navigated transcranial magnetic stimulation (nTMS) gains increasing importance in presurgical language mapping. Although bipolar direct cortical stimulation (DCS) is regarded as the gold standard for intraoperative mapping of language-related areas, it cannot be used to map the healthy human brain due to its invasive character. Therefore, the present study employed a non-invasive virtual-lesion modality to provide a causality-confirmed cortical language map of the healthy human brain by repetitive nTMS (rTMS) with functional specifications beyond language-positive/language-negative distinction. Fifty right-handed healthy volunteers underwent rTMS language mapping of the left hemisphere combined with an object-naming task. The induced errors were categorized and frequency maps were calculated. Moreover, a principal component analysis (PCA) was performed on the basis of language-positive cortical regions for each error category. The left hemisphere was stimulated at 258-789 sites (median: 361.5 sites), and 12-241 naming errors (median: 72.5 errors) were observed. In male subjects, a total number of 2091 language errors were elicited by 9579 stimulation trains, which is equal to an error rate of 21.8 %. Within females, 10,238 stimulation trains elicited 2032 language errors (19.8 %). PCA revealed that the inferior parietal lobe (IPL) and middle frontal gyrus (MFG) were causally involved in object naming as a semantic center and an executive control center. For the first time, this study provides causality-based data and a model that approximates the distribution of language-related cortical areas grouped for different functional aspects of single-word production processes by PCA.
authors.affiliation: Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany. sandro.krieg@lrz.tum.de.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany. sandro.krieg@lrz.tum.de.
authors.forename: Sandro M
authors.identifier: 0000-0003-4050-1531
authors.initials: SM
authors.lastname: Krieg
authors.affiliation: Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.|TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Nico
authors.initials: N
authors.lastname: Sollmann
authors.affiliation: Faculty of Linguistics, Philology, and Phonetics, University of Oxford, Walton Street, Oxford, OX1 2HG, UK.
authors.forename: Noriko
authors.initials: N
authors.lastname: Tanigawa
authors.affiliation: Section of Neuroradiology, Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Foerschler
authors.affiliation: Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Meyer
authors.affiliation: Department of Neurosurgery, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str. 22, 81675, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Ringel
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D056344:Executive Function / Q000502:physiology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D038361:Neuronavigation / Q000379:methods*; D010296:Parietal Lobe / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology; D012660:Semantics; D013060:Speech; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D055815:Young Adult
keywords: Cortical mapping; Language; Navigated brain stimulation; Object naming; Transcranial magnetic stimulation