Organization of language areas in bilingual patients: a cortical stimulation study

2002 ◽  
Vol 97 (4) ◽  
pp. 857-864 ◽  
Author(s):  
Franck-Emmanuel Roux ◽  
Michel Trémoulet
Keyword(s):  
Language Proficiency ◽  
Word Retrieval ◽  
Cortical Mapping ◽  
Content Type ◽  
Cortical Areas ◽  
Language Deficit ◽  
Language Studies ◽  
Language Difficulties ◽  
Language Areas ◽  
Fine Print

Object. In an attempt to gain a better understanding of how multiple languages are represented in the human brain, the authors studied bilingual patients who underwent surgery for brain tumors, during which the authors mapped cortical language sites by using electrostimulation. Methods. Reading, counting, and word retrieval tasks were studied in 12 right-handed bilingual patients with no language deficit. All bilingual patients were native to France. One patient spoke four languages. The patients constituted a nonhomogeneous group in terms of language proficiency or age of acquisition. Languages were evaluated and classified into three major groups, depending on proficiency and date of acquisition. Strict conditions of language site validation were applied, separating typical anomia sites from speech arrest or other language sites (such as hesitation sites). A total of 30 speech arrest sites, 16 anomia sites, and three sites of language difficulties (not typically classified as speech arrest) were found throughout the 26 language studies performed. Strict overlapping of language areas (for all language tasks) was found in five patients, whereas the remaining seven had at least one area that was language-specific and sometimes task-specific. Specific areas for a particular language were found for word retrieval tasks (anomia) in eight sites (50%) but also in six (20%) of the reading or counting sites (speech arrest), either in frontal (three patients) or in temporoparietal (four patients) regions. Among the four early bilingual patients tested (languages acquired before the age of 7 years), three had language-specific cortical areas. Interestingly, six patients in this series who had a discrepancy between two languages did not have more cortical areas devoted to the less proficient language (with acknowledgment of the limit in cortical exposure available for testing by the craniotomy). Conclusions. In this series, the authors found that bilingual patients could have common but also different cortical areas for both languages in temporoparietal areas and in frontal areas. In some cases, the authors found that language tasks such as counting, reading, or word retrieval in different languages can be sustained by language- and task-specific cortical areas. In bilingual patients, cortical mapping should ideally be performed using different language tasks in all languages in which the patient is fluent.

Category-specific cortical mapping: color-naming areas

2006 ◽  
Vol 104 (1) ◽  
pp. 27-37 ◽  
Author(s):  
Franck-Emmanuel Roux ◽  
Vincent Lubrano ◽  
Valérie Lauwers-Cances ◽  
Christopher R. Mascott ◽  
Jean-François Démonet
Keyword(s):  
Electrical Stimulation ◽  
Naming Task ◽  
Color Naming ◽  
Individual Variability ◽  
Cortical Mapping ◽  
Object Naming ◽  
Cortical Areas ◽  
Language Deficit ◽  
Language Areas ◽  
Naming Tasks

Object It has been hypothesized that a certain degree of specialization exists within language areas, depending on some specific lexical repertories or categories. To spare hypothetical category-specific cortical areas and to gain a better understanding of their organization, the authors studied patients who had undergone electrical stimulation mapping for brain tumors and they compared an object-naming task with a category-specific task (color naming). Methods Thirty-six patients with no significant preoperative language deficit were prospectively studied during a 2-year period. Along with a reading task, both object- and color-naming tasks were used in brain mapping. During color naming, patients were asked to identify 11 visually presented basic colors. The modality specificity of the colornaming sites found was subsequently tested by asking patients to retrieve the color attributes of objects. High individual variability was observed in language organization among patients and in the tasks performed. Significant interferences in color naming were found in traditional language regions—that is, Broca (p < 0.003) and Wernicke centers (p = 0.05)—although some color-naming areas were occasionally situated outside of these regions. Color-naming interferences were exclusively localized in small cortical areas (< 1 cm2). Anatomical segregation of the different naming categories was apparent in 10 patients; in all, 13 color-specific naming areas (that is, sites evoking no object-naming interference) were detected in the dominant-hemisphere F3 and the supramarginal, angular, and posterior parts of the temporal gyri. Nevertheless, no specific brain region was found to be consistently involved in color naming (p > 0.05). At five sites, although visually presented color-naming tasks were impaired by stimulation, auditory color naming (for example, “What color is grass?”) was performed with no difficulty, showing that modality-specific areas can be found during naming. Conclusions Within language areas, a relative specialization of cortical language areas for color naming can be found during electrical stimulation mapping.

Preoperative predictors of anterior temporal language areas

1998 ◽  
Vol 89 (6) ◽  
pp. 962-970 ◽  
Author(s):  
Theodore H. Schwartz ◽  
Orrin Devinsky ◽  
Werner Doyle ◽  
Kenneth Perrine
Keyword(s):  
Temporal Lobe ◽  
Right Hemisphere ◽  
Temporal Lobectomy ◽  
Seizure Onset ◽  
Anterior Temporal Lobe ◽  
Verbal Iq ◽  
Content Type ◽  
Language Areas ◽  
Fine Print

Object. Although it is known that 5 to 10% of patients have language areas anterior to the rolandic cortex, many surgeons still perform standard anterior temporal lobectomies for epilepsy of mesial onset and report minimal long-term dysphasia. The authors examined the importance of language mapping before anterior temporal lobectomy. Methods. The authors mapped naming, reading, and speech arrest in a series of 67 patients via stimulation of long-term implanted subdural grids before resective epilepsy surgery and correlated the presence of language areas in the anterior temporal lobe with preoperative demographic and neuropsychometric data. Naming (p < 0.03) and reading (p < 0.05) errors were more common than speech arrest in patients undergoing surgery in the anterior temporal lobe. In the approximate region of a standard anterior temporal lobectomy, including 2.5 cm of the superior temporal gyrus and 4.5 cm of both the middle and inferior temporal gyrus, the authors identified language areas in 14.5% of patients tested. Between 1.5 and 3.5 cm from the temporal tip, patients who had seizure onset before 6 years of age had more naming (p < 0.02) and reading (p < 0.01) areas than those in whom seizure onset occurred after age 6 years. Patients with a verbal intelligence quotient (IQ) lower than 90 had more naming (p < 0.05) and reading (p < 0.02) areas than those with an IQ higher than 90. Finally, patients who were either left handed or right hemisphere memory dominant had more naming (p < 0.05) and reading (p < 0.02) areas than right-handed patients with bilateral or left hemisphere memory lateralization. Postoperative neuropsychometric testing showed a trend toward a greater decline in naming ability in patients who were least likely to have anterior language areas, that is, those with higher verbal IQ and later seizure onset. Conclusions. Preoperative identification of markers of left hemisphere damage, such as early seizure onset, poor verbal IQ, left handedness, and right hemisphere memory dominance should alert neurosurgeons to the possibility of encountering essential language areas in the anterior temporal lobe (1.5–3.5 cm from the temporal tip). Naming and reading tasks are required to identify these areas. Whether removal of these areas necessarily induces long-term impairment in verbal abilities is unknown; however, in patients with a low verbal IQ and early seizure onset, these areas appear to be less critical for language processing.

“The Mute Who Can Sing”: a cortical stimulation study on singing

2009 ◽  
Vol 110 (2) ◽  
pp. 282-288 ◽  
Author(s):  
Franck-Emmanuel Roux ◽  
Stefano Borsa ◽  
Jean-François Démonet
Keyword(s):  
Brain Tumors ◽  
Special Interest ◽  
Clear Distinction ◽  
Awake Surgery ◽  
Cortical Mapping ◽  
Cortical Areas ◽  
Left Handed ◽  
Surgical Data ◽  
The Right ◽  
Language Areas

Object In an attempt to identify cortical areas involved in singing in addition to language areas, the authors used a singing task during direct cortical mapping in 5 patients who were amateur singers and had undergone surgery for brain tumors. The organization of the cortical areas involved in language and singing was analyzed in relation with these surgical data. Methods One left-handed and 4 right-handed patients with brain tumors in left (2 cases) and right (3 cases) hemispheres and no significant language or singing deficits underwent surgery with the “awake surgery” technique. All patients had a special interest in singing and were involved in amateur singing activities. They were tested using naming, reading, and singing tasks. Results Outside primary sensorimotor areas, singing interferences were rare and were exclusively localized in small cortical areas (< 1 cm2). A clear distinction was found between speech and singing in the Broca region. In the Broca region, no singing interference was found in areas in which interference in naming and reading tasks were detected. Conversely, a specific singing interference was found in nondominant middle frontal gyri in one patient. This interference consisted of abrupt singing arrest without apparent face, mouth, and tongue contraction. Finally, nonspecific singing interferences were found in the right and left precentral gyri in all patients (probably by interference in final articulatory mechanisms of singing). Conclusions Dissociations between speech and singing found outside primary sensorimotor areas showed that these 2 functions use, in some cortical stages, different cerebral pathways.

Microvascular bypass surgery

1976 ◽  
Vol 44 (6) ◽  
pp. 712-714 ◽  
Author(s):  
Norman Chater ◽  
Robert Spetzler ◽  
Kent Tonnemacher ◽  
Charles B. Wilson
Keyword(s):  
Frontal Lobe ◽  
Temporal Lobe ◽  
Bypass Surgery ◽  
Angular Gyrus ◽  
Anatomical Studies ◽  
Content Type ◽  
Cortical Areas ◽  
Cortical Vessel ◽  
Suitable Location ◽  
Fine Print

✓ Microvascular anatomical studies were performed to ascertain the most suitable cortical vessel for extracranial-intracranial arterial bypass (EIAB). The three most commonly used cortical areas (the tip of the frontal lobe, the tip of the temporal lobe, and the area at the angular gyrus) were examined in detail. Because of their accessibility and size, the cortical arteries in the area of the angular gyrus offer the most suitable location for creating an EIAB.

Writing-specific sites in frontal areas: a cortical stimulation study

2004 ◽  
Vol 101 (5) ◽  
pp. 787-798 ◽  
Author(s):  
Vincent Lubrano ◽  
Franck-Emmanuel Roux ◽  
Jean-François Démonet
Keyword(s):  
Brain Tumors ◽  
Individual Variability ◽  
Cortical Stimulation ◽  
Awake Surgery ◽  
Direct Stimulation ◽  
Content Type ◽  
Left Handed ◽  
Language Areas ◽  
Fine Print ◽  
Stimulation Of

Object. The aim of this study was to determine whether cortical areas involved in the writing process are associated with reading or naming areas in patients undergoing surgery for brain tumors in frontal areas. This study was undertaken to spare all language areas found in patients during surgery. Methods. Fourteen patients (eight women and six men [mean age 47 years] of whom 12 were right handed, two left handed, 12 monolingual, and two bilingual) who harbored brain tumors in the left (11 patients) or right (three patients) frontal gyri or in rolandic areas, were tested by direct stimulation by using the awake surgery technique for direct brain mapping. Mapping of the frontal gyri was performed using naming, reading, and writing under dictation tasks in the appropriate language(s). Considerable individual variability in language organization among patients was observed. Interferences in writing were found during direct stimulation in the frontal gyri, in cortical sites common or not common to interferences in naming or reading. In dominant regions, patterns of writing dysfunctions were variable and included writing arrest, illegible script, letter omissions, and paragraphia. These dysfunctions were nonspecific (stimulation-induced eye movements) in nondominant frontal regions and in rolandic gyri (hand contractions). In the same patient, different writing impairments could sometimes be observed during stimulation of different sites. As is the case for naming or reading interference sites, writing interference sites could be extremely localized (1 cm2 in diameter). In this group of patients, writing interference sites found in Broca areas were associated with other sites of language interference, whereas writing-specific interference sites were found twice in the dominant middle frontal gyrus. Conclusions. In this series, we found that writing interference sites could be detected by direct cortical stimulation in dominant inferior and middle frontal gyri regardless of whether they were associated with naming or reading interference sites. Writing disorders elicited by direct stimulation in the frontal lobes are varied and probably depend on the functional status of the stimulated cortical area.

Discordance between functional magnetic resonance imaging during silent speech tasks and intraoperative speech arrest

2005 ◽  
Vol 103 (2) ◽  
pp. 267-274 ◽  
Author(s):  
Nicole Petrovich ◽  
Andrei I. Holodny ◽  
Viviane Tabar ◽  
Denise D. Correa ◽  
Joy Hirsch ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Inferior Frontal Gyrus ◽  
Hemispheric Dominance ◽  
Cortical Mapping ◽  
Precentral Gyrus ◽  
Functional Magnetic Resonance ◽  
Content Type ◽  
Neurosurgical Planning ◽  
Silent Speech ◽  
Fine Print

Object. The goal of this study was to investigate discordance between the location of speech arrest during awake cortical mapping, a common intraoperative indicator of hemispheric dominance, and silent speech functional magnetic resonance (fMR) imaging maps of frontal language function. Methods. Twenty-one cases were reviewed retrospectively. Images of silent speech fMR imaging activation were coregistered to anatomical MR images obtained for neuronavigation. These were compared with the intraoperative cortical photographs and the behavioral results of electrocorticography during awake craniotomy. An fMR imaging control study of three healthy volunteers was then conducted to characterize the differences between silent and vocalized speech fMR imaging protocols used for neurosurgical planning. Conclusions. Results of fMR imaging showed consistent and predominant activation of the inferior frontal gyrus (IFG) during silent speech tasks. During intraoperative mapping, however, 16 patients arrested in the precentral gyrus (PRG), well posterior to the fMR imaging activity. Of those 16, 14 arrested only in the PRG and not in the IFG as silent speech fMR imaging predicted. The control fMR imaging study showed that vocalized speech fMR imaging shifts the location of the fMR imaging prediction to include the motor strip and may be more appropriate for neurosurgical planning.

Localization of human frontal eye fields: anatomical and functional findings of functional magnetic resonance imaging and intracerebral electrical stimulation

2001 ◽  
Vol 95 (5) ◽  
pp. 804-815 ◽  
Author(s):  
Elie Lobel ◽  
Philippe Kahane ◽  
Ute Leonards ◽  
Marie-Hélène Grosbras ◽  
Stéphane Lehéricy ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Eye Movements ◽  
Magnetic Resonance ◽  
3 Tesla ◽  
Frontal Eye Fields ◽  
Precentral Gyrus ◽  
Functional Magnetic Resonance ◽  
Content Type ◽  
Cortical Areas ◽  
Fine Print

Object. The goal of this study was to investigate the anatomical localization and functional role of human frontal eye fields (FEFs) by comparing findings from two independently conducted studies. Methods. In the first study, 3-tesla functional magnetic resonance (fMR) imaging was performed in 14 healthy volunteers divided into two groups: the first group executed self-paced voluntary saccades in complete darkness and the second group repeated newly learned or familiar sequences of saccades. In the second study, intracerebral electrical stimulation (IES) was performed in 38 patients with epilepsy prior to surgery, and frontal regions where stimulation induced versive eye movements were identified. These studies showed that two distinct oculomotor areas (OMAs) could be individualized in the region classically corresponding to the FEFs. One OMA was consistently located at the intersection of the superior frontal sulcus with the fundus of the superior portion of the precentral sulcus, and was the OMA in which saccadic eye movements could be the most easily elicited by electrical stimulation. The second OMA was located more laterally, close to the surface of the precentral gyrus. The fMR imaging study and the IES study demonstrated anatomical and stereotactic agreement in the identification of these cortical areas. Conclusions. These findings indicate that infracentimetric localization of cortical areas can be achieved by measuring the vascular signal with the aid of 3-tesla fMR imaging and that neuroimaging and electrophysiological recording can be used together to obtain a better understanding of the human cortical functional anatomy.

Intracranial navigation by using low-field intraoperative magnetic resonance imaging: preliminary experience

2002 ◽  
Vol 97 (5) ◽  
pp. 1115-1124 ◽  
Author(s):  
Andrew A. Kanner ◽  
Michael A. Vogelbaum ◽  
Marc R. Mayberg ◽  
Joseph P. Weisenberger ◽  
Gene H. Barnett
Keyword(s):  
Magnetic Resonance ◽  
Imaging System ◽  
Intraoperative Imaging ◽  
Tumor Resection ◽  
Cortical Mapping ◽  
Subtotal Resection ◽  
Neurosurgical Procedures ◽  
Content Type ◽  
Low Field ◽  
Fine Print

Object. Intracranial navigation by using intraoperative magnetic resonance (iMR) imaging allows the surgeon to reassess anatomical relationships in near—real time during brain tumor surgery. The authors report their initial experience with a novel neuronavigation system coupled to a low-field iMR imaging system. Methods. Between October 2000 and December 2001, 70 neurosurgical procedures were performed using the mobile 0.12-tesla PoleStar N-10 iMR imaging system. The cases included 38 craniotomies, 15 brain biopsies, nine transsphenoidal approaches, and one drainage of a subdural hematoma. Tumor resection was performed using the awake method in seven of 38 cases. Of the craniotomies, image-confirmed complete or radical tumor resection was achieved in 28 cases, subtotal resection in eight cases, and open biopsies in two cases. Tumor resection was controlled with the use of image guidance until the final intraoperative images demonstrated that there was no residual tumor or that no critical brain tissue was at risk of compromise. In each stereotactic biopsy the location of the biopsy needle could be verified by intraoperative imaging and diagnostic tissue was obtained. Complications included a case of aseptic meningitis after a biopsy and one case of temporary intraoperative failure of the anesthesia machine. Awake craniotomies were performed successfully with no permanent neurological complications. Conclusions. Intraoperative MR image—based neuronavigation is feasible when using the Odin PoleStar N-10 system for tumor resections that require multiple other surgical adjuncts including awake procedures, cortical mapping, monitoring of somatosensory evoked potentials, or electrocorticography. Use of the system for brain biopsies offers the opportunity of immediate verification of the needle tip location. Standard neurosurgical drills, microscopes, and other equipment can be used safely in conjunction with this iMR imaging system.

Cortical stimulation mapping of language cortex by using a verb generation task: effects of learning and comparison to mapping based on object naming

2002 ◽  
Vol 97 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Jeffrey G. Ojemann ◽  
George A. Ojemann ◽  
Ettore Lettich
Keyword(s):  
Functional Neuroimaging ◽  
Cortical Stimulation ◽  
Object Naming ◽  
Generation Task ◽  
Content Type ◽  
Cortical Stimulation Mapping ◽  
Verb Generation ◽  
Language Areas ◽  
Language Cortex ◽  
Fine Print

Object. Cortical stimulation mapping has traditionally relied on disruption of object naming to define essential language areas. In this study, the authors reviewed the use of a different language task, verb generation, in mapping language. This task has greater use in brain imaging studies and may be used to test aspects of language different from those of object naming. Methods. In 14 patients, cortical stimulation mapping performed using a verb generation task provided a map of language areas in the frontal and temporoparietal cortices. These verb generation maps often overlapped object naming ones and, in many patients, different areas of cortex were found to be involved in the two functions. In three patients, stimulation mapping was performed during the initial performance of the verb generation task and also during learned performance of the task. Parallel to findings of published neuroimaging studies, a larger area of stimulated cortex led to disruption of verb generation in response to stimulation during novel task performance than during learned performance. Conclusions. Results of cortical stimulation mapping closely resemble those of functional neuroimaging when both implement the verb generation task. The precise map of the temporoparietal language cortex depends on the task used for mapping.

Localization of language function in children: results of electrical stimulation mapping

2003 ◽  
Vol 98 (3) ◽  
pp. 465-470 ◽  
Author(s):  
Steven G. Ojemann ◽  
Mitchel S. Berger ◽  
Ettore Lettich ◽  
George A. Ojemann
Keyword(s):  
Electrical Stimulation ◽  
Language Function ◽  
Content Type ◽  
Site Distribution ◽  
Relative Paucity ◽  
Younger Age ◽  
Language Areas ◽  
Relationship Of ◽  
The Relationship ◽  
Fine Print

Object. The authors examined the localization of language sites and the frequency of naming errors at these sites in a population of children undergoing electrical stimulation mapping during surgeries in which epileptic foci and dominant hemisphere neoplasms were resected. The frequency with which essential language sites were found (that is, “the frequency of language sites”) in children was compared with that of a population of adults who had undergone this procedure, to assess the relationship of age to the distribution of essential areas for language. Methods. The results of electrical stimulation mapping to determine sites of naming and speech arrest in 26 children ranging in ages from 4 to 16 years are presented in this report. Mapping was performed in the intraoperative setting in eight patients and in the extraoperative setting, by stimulation across a subdural grid, in 18 patients. The frequency and distribution of essential language areas were analyzed in populations of different ages and according to the method used to obtain the map. Considerable variability was found in the localization of language sites. When the language site distribution in pediatric patients was compared with the language site distribution found previously in a population of patients older than 16 years of age, a relative paucity of language sites was found in all perisylvian cortices in the younger age group. This relationship was also found within the group of patients 16 years of age and younger, when segregated into two groups: those patients 8 years of age or younger, and those patients between 9 and 16 years of age. These findings are relevant to theories of the intrahemispheric organization of the cortex devoted to language function. Conclusions. The differences found between groups of younger and older patients in the frequencies of sites where stimulation produces naming errors was identified suggests the possibility that, with advancing age, maturational processes contribute new foci of cortex essential for language.

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