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Wolfdieter Heiss - One of the best experts on this subject based on the ideXlab platform.
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from the left to the right how the brain compensates progressive loss of Language Function
Brain and Language, 2006Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:In normal right-handed subjects Language production usually is a Function oft the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this Function. Sometimes, but not always, areas of the right hemisphere which are homologous to Language areas of the left hemisphere in normal subjects are successfully employed for compensation but this integration process may need time to develop. We investigated right-handed patients with left hemisphere brain tumors as a model of continuously progressive brain damage to left hemisphere Language areas using Functional neuroimaging and transcranial magnetic stimulation (TMS) to identify factors which determine successful compensation of lost Language Function. Only patients with slowly progressing brain lesions recovered right-sided Language Function as detected by TMS. In patients with rapidly progressive lesions no right-sided Language Function was found and Language performance was linearly correlated with the lateralization of Language related brain activation to the left hemisphere. It can thus be concluded that time is the factor which determines successful integration of the right hemisphere into the Language network for compensation of lost left hemisphere Language Function.
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role of the contralateral inferior frontal gyrus in recovery of Language Function in poststroke aphasia a combined repetitive transcranial magnetic stimulation and positron emission tomography study
Stroke, 2005Co-Authors: Lutz Winhuisen, Alexander Thiel, Josef Kessler, W F Haupt, Birgit Schumacher, J Rudolf, Wolfdieter HeissAbstract:Background and Purpose— Functional neuroimaging studies have demonstrated right inferior frontal gyrus (IFG) activation in poststroke aphasia. It remains unclear whether this activation is essential for Language performance. We tested this hypothesis in a positron emission tomography (PET) activation study during a semantic task with repetitive transcranial magnetic stimulation (rTMS) on right-handed patients experiencing poststroke aphasia and examined whether rTMS stimulation over the right and left IFG would interfere with Language performance. Methods— Eleven patients with left-sided middle cerebral arterial infarction, 50 to 75 years of age, were tested with the Aachen Aphasia Test Battery and underwent 15O-H2O PET activation during a semantic task within 2 weeks after stroke. PET activation images were coregistered to T1-weighted MRIs. Stimulation sites were determined on renderings of head and brain over the maximum activation within left and right IFG. rTMS was performed with 20% maximum output (2...
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essential Language Function of the right hemisphere in brain tumor patients
Annals of Neurology, 2005Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:Department of Neurology, University of Cologne, Cologne, Germany. A.Thiel@pet.mpin-koeln.mpg.deNeuroimaging studies of Language networks in patients with brain lesions of the left Language-dominant hemisphere have shown activation in the right inferior frontal gyrus (IFG). We tested the Functional relevance of right IFG activation using neuroimaging-guided repetitive transcranial magnetic stimulation (rTMS) to disturb Language Function over bilateral IFG in right-handed patients with brain tumors and controls. All subjects were susceptible to TMS over the left IFG. In patients, this susceptibility correlated with left-sided the degree of Language lateralization to the left. Those patients with lowest dominance were also susceptible to right-sided TMS proving relevant Language Function of the right IFG.PMID: 15622534 [PubMed - indexed for MEDLINE]
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disturbance and recovery of Language Function correlates in pet activation studies
NeuroImage, 2003Co-Authors: Wolfdieter Heiss, Alexander Thiel, Josef Kessler, Karl HerholzAbstract:Abstract Disturbance of neurologic Function in disorders of the central nervous system is expressed as an altered activation pattern in Functional networks employed by specific tasks and can be studied by Functional imaging modalities, e.g., positron emission tomography. Language, a complex brain Function, is based on the interplay of a distributed network in which partial Functions are executed in various centers, the primary Language areas. These areas are hierarchically organized and activated according to the complexity of the specific Language task. The specialization of different centers and the lateralization of integrative Functions into the dominant (usually left) hemisphere are achieved by collateral and transcallosal inhibition of secondary Language areas which normally are not employed for performance of a specific Language task.
Alexander Thiel - One of the best experts on this subject based on the ideXlab platform.
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from the left to the right how the brain compensates progressive loss of Language Function
Brain and Language, 2006Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:In normal right-handed subjects Language production usually is a Function oft the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this Function. Sometimes, but not always, areas of the right hemisphere which are homologous to Language areas of the left hemisphere in normal subjects are successfully employed for compensation but this integration process may need time to develop. We investigated right-handed patients with left hemisphere brain tumors as a model of continuously progressive brain damage to left hemisphere Language areas using Functional neuroimaging and transcranial magnetic stimulation (TMS) to identify factors which determine successful compensation of lost Language Function. Only patients with slowly progressing brain lesions recovered right-sided Language Function as detected by TMS. In patients with rapidly progressive lesions no right-sided Language Function was found and Language performance was linearly correlated with the lateralization of Language related brain activation to the left hemisphere. It can thus be concluded that time is the factor which determines successful integration of the right hemisphere into the Language network for compensation of lost left hemisphere Language Function.
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role of the contralateral inferior frontal gyrus in recovery of Language Function in poststroke aphasia a combined repetitive transcranial magnetic stimulation and positron emission tomography study
Stroke, 2005Co-Authors: Lutz Winhuisen, Alexander Thiel, Josef Kessler, W F Haupt, Birgit Schumacher, J Rudolf, Wolfdieter HeissAbstract:Background and Purpose— Functional neuroimaging studies have demonstrated right inferior frontal gyrus (IFG) activation in poststroke aphasia. It remains unclear whether this activation is essential for Language performance. We tested this hypothesis in a positron emission tomography (PET) activation study during a semantic task with repetitive transcranial magnetic stimulation (rTMS) on right-handed patients experiencing poststroke aphasia and examined whether rTMS stimulation over the right and left IFG would interfere with Language performance. Methods— Eleven patients with left-sided middle cerebral arterial infarction, 50 to 75 years of age, were tested with the Aachen Aphasia Test Battery and underwent 15O-H2O PET activation during a semantic task within 2 weeks after stroke. PET activation images were coregistered to T1-weighted MRIs. Stimulation sites were determined on renderings of head and brain over the maximum activation within left and right IFG. rTMS was performed with 20% maximum output (2...
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essential Language Function of the right hemisphere in brain tumor patients
Annals of Neurology, 2005Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:Department of Neurology, University of Cologne, Cologne, Germany. A.Thiel@pet.mpin-koeln.mpg.deNeuroimaging studies of Language networks in patients with brain lesions of the left Language-dominant hemisphere have shown activation in the right inferior frontal gyrus (IFG). We tested the Functional relevance of right IFG activation using neuroimaging-guided repetitive transcranial magnetic stimulation (rTMS) to disturb Language Function over bilateral IFG in right-handed patients with brain tumors and controls. All subjects were susceptible to TMS over the left IFG. In patients, this susceptibility correlated with left-sided the degree of Language lateralization to the left. Those patients with lowest dominance were also susceptible to right-sided TMS proving relevant Language Function of the right IFG.PMID: 15622534 [PubMed - indexed for MEDLINE]
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disturbance and recovery of Language Function correlates in pet activation studies
NeuroImage, 2003Co-Authors: Wolfdieter Heiss, Alexander Thiel, Josef Kessler, Karl HerholzAbstract:Abstract Disturbance of neurologic Function in disorders of the central nervous system is expressed as an altered activation pattern in Functional networks employed by specific tasks and can be studied by Functional imaging modalities, e.g., positron emission tomography. Language, a complex brain Function, is based on the interplay of a distributed network in which partial Functions are executed in various centers, the primary Language areas. These areas are hierarchically organized and activated according to the complexity of the specific Language task. The specialization of different centers and the lateralization of integrative Functions into the dominant (usually left) hemisphere are achieved by collateral and transcallosal inhibition of secondary Language areas which normally are not employed for performance of a specific Language task.
Bernhard Meyer - One of the best experts on this subject based on the ideXlab platform.
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Language-Eloquent White Matter Pathway Tractography and the Course of Language Function in Glioma Patients
Frontiers in Oncology, 2018Co-Authors: Sebastian Ille, Lara Engel, Anna Kelm, Bernhard Meyer, Sandro M. KriegAbstract:Object: As various recent studies show, damage to white matter pathways leads to permanent Functional deficits in a high percentage of patients. Particularly the subcortical Language network is complex, and its visualization has a tremendous relevance for neurosurgeons. This pilot study aims to correlate Language-eloquent white matter pathways with the course of Language Function after the resection of left-sided perisylvian gliomas. Methods: We included 10 patients who underwent resection of highly Language-eloquent high- (9 pts) and low-grade gliomas (1 pts). We performed navigated repetitive transcranial magnetic stimulation (nrTMS)-based tractography via diffusion tensor imaging fiber trackings (DTI FT) preoperatively (PRE-1), postoperatively (POST-1), and at long-term follow up or tumor recurrence (PRE-2). We separately tracked the inferior fronto-occipital fascicle (IFOF), the frontal aslant tract (FAT), and the superior longitudinal (SLF), and arcuate fascicle (AF), and correlated the amount of visualized fibers to the patients' Language Function at each date. Results: The changes of nrTMS-based DTI FTs of single white matter pathways correlated with the according status of Language Function for any of the pathways in 80% of patients and in 19 of 30 (63%) single pathway comparisons between PRE-1 and POST-1. Between POST-1 and PRE-2 the nrTMS-based DTI FTs correlated with the status of Language Function for any of the pathways in all patients and in 24 of 30 (80%) single pathway comparisons. Single FT results correlated with the according status of Language Function at POST-1 in 60, 70, and 60% of cases, and with the according status of Language Function at PRE-2 in 60, 90, and 90% of cases for the tracking of the IFOF, FAT, and SLF/AF, respectively. Conclusion: By the present results we were able to show that nrTMS-based DTI FT of the IFOF, FAT, and SLF/AF mainly correlates with the according status of Language Function preoperatively, postoperatively, and at long-term follow up after the resection of left-sided perisylvian gliomas.
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interhemispheric connectivity revealed by diffusion tensor imaging fiber tracking derived from navigated transcranial magnetic stimulation maps as a sign of Language Function at risk in patients with brain tumors
Journal of Neurosurgery, 2017Co-Authors: Nico Sollmann, Florian Ringel, Sebastian Ille, Lorena Tussis, Chiara Negwer, Theresa Hauck, Stefanie Maurer, Katrin Giglhuber, Jan S Bauer, Bernhard MeyerAbstract:OBJECTIVE Resection of brain tumors in Language-eloquent areas entails the risk of postoperative aphasia. It has been demonstrated via navigated transcranial magnetic stimulation (nTMS) that Language Function can partially shift to the unaffected hemisphere due to tumor-induced plasticity. Therefore, this study was designed to evaluate whether interhemispheric connectivity (IC) detected by nTMS-based diffusion tensor imaging-fiber tracking (DTI-FT) can be used to predict surgery-related aphasia in patients with brain tumors. METHODS Thirty-eight patients with left-sided perisylvian brain lesions underwent cortical Language mapping of both hemispheres by nTMS prior to awake surgery. Then, nTMS-based DTI-FT was conducted with a fractional anisotropy (FA) of 0.01 and 0.2 to visualize nTMS-based IC. Receiver operating characteristics were calculated for the prediction of a postoperative (irrespective of the preoperative state) and a new surgery-related aphasia by the presence of detectable IC. RESULTS Language mapping by nTMS was possible in all patients. Seventeen patients (44.7%) suffered from surgery-related worsening of Language performance (transient aphasia according to 3-month follow-up in 16 subjects [42.1%]; new permanent aphasia according to 3-month follow-up in 1 patient [2.6%]). Regarding the correlation of aphasia to nTMS-based IC, statistically significant differences were revealed for both evaluated FA values. However, better results were observed for tractography with an FA of 0.2, which led to a specificity of 93% (postoperative aphasia) and 90% (surgery-related aphasia). For postoperative aphasia, the corresponding OR was 0.1282 (95% CI 0.0143-1.1520), and for surgery-related aphasia the OR was 0.1184 (95% CI 0.0208-0.6754). CONCLUSIONS According to these results, IC detected by preoperative nTMS-based DTI-FT might be regarded as a risk factor for surgery-related aphasia, with a specificity of up to 93%. However, because the majority of enrolled patients suffered from transient aphasia postoperatively, it has to be evaluated whether this approach distinctly leads to similar results among patients with permanent Language deficits. Despite this restriction, this approach might contribute to individualized patient consultation prior to tumor resection in clinical practice.
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Language Function distribution in left handers a navigated transcranial magnetic stimulation study
Neuropsychologia, 2016Co-Authors: Lorena Tussis, Bernhard Meyer, Nico Sollmann, Tobias Boeckhbehrens, Sandro M. KriegAbstract:Recent studies suggest that in left-handers, the right hemisphere (RH) is more involved in Language Function when compared to right-handed subjects. Since data on lesion-based approaches is lacking, we aimed to investigate Language distribution of left-handers by repetitive navigated transcranial magnetic stimulation (rTMS). Thus, rTMS was applied to the left hemisphere (LH) and RH in 15 healthy left-handers during an object-naming task, and resulting naming errors were categorized. Then, we calculated error rates (ERs=number of errors per number of stimulations) for both hemispheres separately and defined a laterality score as the quotient of the LH ER - RH ER through the LH ER + RH ER (abbreviated as (L-R)/(L+R)). In this context, (L-R)/(L+R)>0 indicates that the LH is dominant, whereas (L-R)/(L+R)<0 shows that the RH is dominant. No significant difference in ERs was found between hemispheres (all errors: mean LH 18.0±11.7%, mean RH 18.1±12.2%, p=0.94; all errors without hesitation: mean LH 12.4±9.8%, mean RH 12.9±10.0%, p=0.65; no responses: mean LH 9.3±9.2%, mean RH 11.5±10.3%, p=0.84). However, a significant difference between the results of (L-R)/(L+R) of left-handers and right-handers (source data of another study) for all errors (mean 0.01±0.14 vs. 0.19±0.20, p=0.0019) and all errors without hesitation (mean -0.02±0.20 vs. 0.19±0.28, p=0.0051) was revealed, whereas the comparison for no responses did not show a significant difference (mean: -0.004±0.27 vs. 0.09±0.44, p=0.64). Accordingly, left-handers present a comparatively equal Language distribution across both hemispheres with Language dominance being nearly equally distributed between hemispheres in contrast to right-handers.
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erratum to the impact of repetitive navigated transcranial magnetic stimulation coil positioning and stimulation parameters on human Language Function
European Journal of Medical Research, 2015Co-Authors: Nico Sollmann, Florian Ringel, Sebastian Ille, Bernhard Meyer, Chiara Negwer, Thomas Obermueller, Sandro M. KriegAbstract:Background Repetitive navigated transcranial magnetic stimulation (rTMS) in combination with object naming is able to elicit naming errors by stimulating Language-related brain regions. However, stimulation results mainly depend on coil positioning and stimulation parameters, which have not been investigated since the implementation of neuronavigation to transcranial magnetic stimulation. Therefore, the following three parameters were systematically examined in the present study: coil angulation, stimulation frequency, and stimulation intensity.
Josef Kessler - One of the best experts on this subject based on the ideXlab platform.
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from the left to the right how the brain compensates progressive loss of Language Function
Brain and Language, 2006Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:In normal right-handed subjects Language production usually is a Function oft the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this Function. Sometimes, but not always, areas of the right hemisphere which are homologous to Language areas of the left hemisphere in normal subjects are successfully employed for compensation but this integration process may need time to develop. We investigated right-handed patients with left hemisphere brain tumors as a model of continuously progressive brain damage to left hemisphere Language areas using Functional neuroimaging and transcranial magnetic stimulation (TMS) to identify factors which determine successful compensation of lost Language Function. Only patients with slowly progressing brain lesions recovered right-sided Language Function as detected by TMS. In patients with rapidly progressive lesions no right-sided Language Function was found and Language performance was linearly correlated with the lateralization of Language related brain activation to the left hemisphere. It can thus be concluded that time is the factor which determines successful integration of the right hemisphere into the Language network for compensation of lost left hemisphere Language Function.
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role of the contralateral inferior frontal gyrus in recovery of Language Function in poststroke aphasia a combined repetitive transcranial magnetic stimulation and positron emission tomography study
Stroke, 2005Co-Authors: Lutz Winhuisen, Alexander Thiel, Josef Kessler, W F Haupt, Birgit Schumacher, J Rudolf, Wolfdieter HeissAbstract:Background and Purpose— Functional neuroimaging studies have demonstrated right inferior frontal gyrus (IFG) activation in poststroke aphasia. It remains unclear whether this activation is essential for Language performance. We tested this hypothesis in a positron emission tomography (PET) activation study during a semantic task with repetitive transcranial magnetic stimulation (rTMS) on right-handed patients experiencing poststroke aphasia and examined whether rTMS stimulation over the right and left IFG would interfere with Language performance. Methods— Eleven patients with left-sided middle cerebral arterial infarction, 50 to 75 years of age, were tested with the Aachen Aphasia Test Battery and underwent 15O-H2O PET activation during a semantic task within 2 weeks after stroke. PET activation images were coregistered to T1-weighted MRIs. Stimulation sites were determined on renderings of head and brain over the maximum activation within left and right IFG. rTMS was performed with 20% maximum output (2...
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essential Language Function of the right hemisphere in brain tumor patients
Annals of Neurology, 2005Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:Department of Neurology, University of Cologne, Cologne, Germany. A.Thiel@pet.mpin-koeln.mpg.deNeuroimaging studies of Language networks in patients with brain lesions of the left Language-dominant hemisphere have shown activation in the right inferior frontal gyrus (IFG). We tested the Functional relevance of right IFG activation using neuroimaging-guided repetitive transcranial magnetic stimulation (rTMS) to disturb Language Function over bilateral IFG in right-handed patients with brain tumors and controls. All subjects were susceptible to TMS over the left IFG. In patients, this susceptibility correlated with left-sided the degree of Language lateralization to the left. Those patients with lowest dominance were also susceptible to right-sided TMS proving relevant Language Function of the right IFG.PMID: 15622534 [PubMed - indexed for MEDLINE]
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disturbance and recovery of Language Function correlates in pet activation studies
NeuroImage, 2003Co-Authors: Wolfdieter Heiss, Alexander Thiel, Josef Kessler, Karl HerholzAbstract:Abstract Disturbance of neurologic Function in disorders of the central nervous system is expressed as an altered activation pattern in Functional networks employed by specific tasks and can be studied by Functional imaging modalities, e.g., positron emission tomography. Language, a complex brain Function, is based on the interplay of a distributed network in which partial Functions are executed in various centers, the primary Language areas. These areas are hierarchically organized and activated according to the complexity of the specific Language task. The specialization of different centers and the lateralization of integrative Functions into the dominant (usually left) hemisphere are achieved by collateral and transcallosal inhibition of secondary Language areas which normally are not employed for performance of a specific Language task.
Lutz Winhuisen - One of the best experts on this subject based on the ideXlab platform.
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from the left to the right how the brain compensates progressive loss of Language Function
Brain and Language, 2006Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:In normal right-handed subjects Language production usually is a Function oft the left brain hemisphere. Patients with aphasia following brain damage to the left hemisphere have a considerable potential to compensate for the loss of this Function. Sometimes, but not always, areas of the right hemisphere which are homologous to Language areas of the left hemisphere in normal subjects are successfully employed for compensation but this integration process may need time to develop. We investigated right-handed patients with left hemisphere brain tumors as a model of continuously progressive brain damage to left hemisphere Language areas using Functional neuroimaging and transcranial magnetic stimulation (TMS) to identify factors which determine successful compensation of lost Language Function. Only patients with slowly progressing brain lesions recovered right-sided Language Function as detected by TMS. In patients with rapidly progressive lesions no right-sided Language Function was found and Language performance was linearly correlated with the lateralization of Language related brain activation to the left hemisphere. It can thus be concluded that time is the factor which determines successful integration of the right hemisphere into the Language network for compensation of lost left hemisphere Language Function.
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role of the contralateral inferior frontal gyrus in recovery of Language Function in poststroke aphasia a combined repetitive transcranial magnetic stimulation and positron emission tomography study
Stroke, 2005Co-Authors: Lutz Winhuisen, Alexander Thiel, Josef Kessler, W F Haupt, Birgit Schumacher, J Rudolf, Wolfdieter HeissAbstract:Background and Purpose— Functional neuroimaging studies have demonstrated right inferior frontal gyrus (IFG) activation in poststroke aphasia. It remains unclear whether this activation is essential for Language performance. We tested this hypothesis in a positron emission tomography (PET) activation study during a semantic task with repetitive transcranial magnetic stimulation (rTMS) on right-handed patients experiencing poststroke aphasia and examined whether rTMS stimulation over the right and left IFG would interfere with Language performance. Methods— Eleven patients with left-sided middle cerebral arterial infarction, 50 to 75 years of age, were tested with the Aachen Aphasia Test Battery and underwent 15O-H2O PET activation during a semantic task within 2 weeks after stroke. PET activation images were coregistered to T1-weighted MRIs. Stimulation sites were determined on renderings of head and brain over the maximum activation within left and right IFG. rTMS was performed with 20% maximum output (2...
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essential Language Function of the right hemisphere in brain tumor patients
Annals of Neurology, 2005Co-Authors: Alexander Thiel, Birgit Habedank, Lutz Winhuisen, Karl Herholz, Josef Kessler, W F Haupt, Wolfdieter HeissAbstract:Department of Neurology, University of Cologne, Cologne, Germany. A.Thiel@pet.mpin-koeln.mpg.deNeuroimaging studies of Language networks in patients with brain lesions of the left Language-dominant hemisphere have shown activation in the right inferior frontal gyrus (IFG). We tested the Functional relevance of right IFG activation using neuroimaging-guided repetitive transcranial magnetic stimulation (rTMS) to disturb Language Function over bilateral IFG in right-handed patients with brain tumors and controls. All subjects were susceptible to TMS over the left IFG. In patients, this susceptibility correlated with left-sided the degree of Language lateralization to the left. Those patients with lowest dominance were also susceptible to right-sided TMS proving relevant Language Function of the right IFG.PMID: 15622534 [PubMed - indexed for MEDLINE]
