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  • 1.
    Börjesson, L.
    et al.
    Linköping University, Department of Neuroscience and Locomotion, Neurology. Linköping University, Faculty of Health Sciences.
    Stockhaus, J.
    Linköping University, Department of Neuroscience and Locomotion, Neurology. Linköping University, Faculty of Health Sciences.
    Gauffin, Helena
    Linköping University, Department of Neuroscience and Locomotion, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Ragnehed, Mattias
    Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Department of Medicine and Care, Radiation Physics. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Söderfeldt, Birgitta
    Linköping University, Department of Neuroscience and Locomotion, Neurology. Linköping University, Faculty of Health Sciences.
    Comparison between fMRI and Wada test2004In: Epilepsia, ISSN 0013-9580, E-ISSN 1528-1167, Vol. 45, no Suppl. 3, p. 84-84Article in journal (Refereed)
    Abstract [en]

    Purpose: Language lateralisation in patients with epilepsy is more often atypical compared to a normal population. The Wada procedure for testing language and memory has some shortcomings; it is invasive and there is always a risk that the patient becomes too sedated, leading to difficulties in performing the tests. fMR1have shown promising results, showing good correlation to the Wadaprocedure concerning language-lateralisation. The aim of this studywas to investigate if fMRI could be used to determine which hemisphere was language dominant and compare the fMR1 results with the Wada-tests with a focus on patients with a complicated lateralisation.

    Method: 4 subjects were tested and they had a heterogeneous (I left handed, I ambidexter and 2 right handed) lateralisation and one had a severe dyslexia. A standard Wada procedure was used and compared with a fMRl investigation using a language paradigm.

    Results: The patients studied showed different language lateralisation patterns (2 left hemisphere and 2 bilateral). In two patients the two tests were fully concordant, in the others the fMRI showed a more bilateral pattern.

    Conclusion: fMR1 adds valuable information in the pre-surgical investigation for patients with a complex language lateralisation.

  • 2.
    Engström, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Karlsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Crone, Marie
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, The Institute of Technology.
    Ragnehed, Mattias
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Antepohl, Wolfram
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Rehabilitation Medicine UHL.
    Landtblom, Anne-Marie
    Linköping University, Department of Clinical and Experimental Medicine, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Department of Medical Specialist.
    Lundberg, Peter
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Clinical fMRI of language function in aphasic patients: Reading paradigm successful, while word generation paradigm fails2010In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 51, no 6, p. 679-686Article in journal (Refereed)
    Abstract [en]

    Background: In fMRI examinations, it is very important to select appropriate paradigms assessing the brain function of interest. In addition, the patients ability to perform the required cognitive tasks during fMRI must be taken into account. Purpose: To evaluate two language paradigms, word generation and sentence reading for their usefulness in examinations of aphasic patients and to make suggestions for improvements of clinical fMRI. Material and Methods: Five patients with aphasia after stroke or trauma sequelae were examined by fMRI. The patients language ability was screened by neurolinguistic tests and elementary pre-fMRI language tests. Results: The sentence-reading paradigm succeeded to elicit adequate language-related activation in perilesional areas whereas the word generation paradigm failed. These findings were consistent with results on the behavioral tests in that all patients showed very poor performance in phonemic fluency, but scored well above mean at a reading comprehension task. Conclusion: The sentence-reading paradigm is appropriate to assess language function in this patient group, while the word-generation paradigm seems to be inadequate. In addition, it is crucial to use elementary pre-fMRI language tests to guide the fMRI paradigm decision.

  • 3.
    Engström, Maria
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Ragnehed, Mattias
    Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics . Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    On the Advantage of Data Driven Analysis in Aphasic Patients with Severe Language Latncy2010Conference paper (Other academic)
  • 4.
    Engström, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences.
    Ragnehed, Mattias
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Projection screen or video goggles as stimulus modality in functional magnetic resonance imaging2005In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 23, no 5, p. 695-699Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to investigate the reliability of functional magnetic resonance imaging (fMRI) by using either a projection screen or video goggles as stimulus modality. A sequence of visual stimuli were presented to the same subject at different occasions. The sequence was optimized with a genetic algorithm. In five sessions the stimuli were presented using a projection screen viewed through a mirror in the head coil and in five sessions using video goggles. Failure to detect visual activation in the medial left hemisphere was observed in sessions using the projection screen as stimulus modality. Decreased thresholds for P values and cluster size resulted in activation outside the occipital lobe and did not significantly increase activated areas in this region. Results in this study indicate that presentation of fMRI tasks with visual routes is more reliable with direct input through video goggles than with the conventional use of projection screens. Failure to detect crucial visual areas has severe consequences for tumor surgery in the visual cortex. Inferior visual impression might also have negative consequences for cognitive tests with high demand on attention and perception.

  • 5.
    Engström, Maria
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Ragnehed, Mattias
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Lundberg, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiation Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Axelsson Söderfeldt, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurology. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Paradigm design of sensory–motor and language tests in clinical fMRI2004In: Neurophysiologie clinique, ISSN 0987-7053, E-ISSN 1769-7131, Vol. 34, no 6, p. 267-277Article in journal (Refereed)
    Abstract [en]

    Functional magnetic resonance imaging (fMRI) paradigms on sensory–motor and language functions are reviewed from a clinical user’s perspective. The objective was to identify special requirements regarding the design of fMRI paradigms for clinical applications. A wide range of methods for setting up fMRI examinations were found in the literature. It was concluded that there is a need for standardised procedures adapted for clinical settings. Sensory–motor activation patterns do not vary much at different hand motion tasks. Nevertheless it is one of the most important clinical tests. In contrast, the language system is much more complex. In several studies it has been observed that word production tasks are preferable in determination of language lateralisation. Broca’s area is activated by most tasks, whereas sentence processing and semantic decision also involve activation in temporoparietal and frontal areas. However, combined task analysis (CTA) of several different tasks has been found to be more robust and reliable for clinical fMRI compared to separate task analysis.

  • 6.
    Fornander, Lotta
    et al.
    Karolinska Institute.
    Nyman, Torbjörn
    Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Anaesthesiology and Intensive Care VHN.
    Hansson, Thomas
    Linköping University, Department of Biomedicine and Surgery, Division of surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Plastic Surgery, Hand surgery UHL.
    Ragnehed, Mattias
    Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences.
    Brismar, Tom
    Karolinska Institute.
    Age- and time-dependent effects on functional outcome and cortical activation pattern in patients with median nerve injury: a functional magnetic resonance imaging study Clinical article2010In: Journal of Neurosurgery, ISSN 0022-3085, E-ISSN 1933-0693, Vol. 113, no 1, p. 122-128Article in journal (Refereed)
    Abstract [en]

    Object. The authors conducted a study to determine age- and time-dependent effects on the functional outcome after median nerve injury and repair and how such effects are related to changes in the pattern of cortical activation in response to tactile stimulation of the injured hand. Methods. The authors studied 11 patients with complete unilateral median nerve injury at the wrist repaired with epineural suture. In addition, 8 patients who were reported on in a previous study were included in the statistical analysis. In the entire study cohort, the mean age at injury was 23.3 +/- 13.4 years (range 7-57 years) and the time after injury ranged from 1 to 11 years. Sensory perception was measured with the static 2-point discrimination test and monofilaments. Functional MR imaging was conducted during tactile stimulation (brush strokes) of Digits II-III and IV-V of both hands, respectively. Results. Tactile sensation was diminished in the median territory in all patients. The strongest predictor of 2-point discrimination was age at injury (p less than 0.0048), and when this was accounted for in the regression analysis, the other age- and time-dependent predictors had no effect. The activation ratios (injured/healthy hand) for Digit II-III and Digit IV-V stimulation were positively correlated (rho 0.59, p less than 0.011). The activation ratio for Digit II-III stimulation correlated weakly with time after injury (p less than 0.041). The activation ratio of Digits IV-V correlated weakly with both age at injury (p less than 0.048) and time after injury (p less than 0.033), but no predictor reached significance in the regression model. The mean ratio of ipsi- and contralateral hemisphere activation after stimulation of the injured hand was 0.55, which was not significantly different from the corresponding ratio of the healthy hand (0.66). Conclusions. Following a median nerve injury (1-11 years after injury) there may be an initial increase in the volume of the cortical representation, which subsequently declines during the restoration phase. These dynamic changes may involve both median and ulnar nerve cortical representation, because both showed negative correlation with time after injury. These findings are in agreement with animal studies showing that cortical plasticity is an important mechanism for functional recovery after peripheral nerve injury and repair.

  • 7.
    Ragnehed, Mattias
    Linköping University, Department of Neuroscience and Locomotion. Linköping University, Department of Biomedical Engineering, Center for Medical Image Science and Visualization. Linköping University, Faculty of Health Sciences.
    Application of fMRI in clinical situations2006Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since its discovery in the early 1990's functional MRI (fMRI) has become the most widely used technique for mapping of brain functions. Its non-invasiveness and the large number of MR-scanners have contributed to the popularity of fMRI. In recent years the interest in using fMRI as a clinical instrument has increased, primarily for pre-operative planning. The purpose of this work is to improve the applicability of fMRI to clinical situations.

    In order to attain the objectives the capacity of analysis methods for fMRI was evaluated, design of paradigms to suit patients was looked into and the effects of an anxiolytic was investigated.

    Especially when fMRI is used in the clinic it is crucial that the analysis method employed is sensitive and reliable. It was confirmed that the method developed by Friman et al. is a worthy competitor to other analysis methods. In general the abilities of patients are reduced compared with healthy volunteer subjects. Therefore one has to design the tasks and task instructions to be readily comprehensible. In addition it is not uncommon that patients are anxious before the examinations and the unfamiliar environment in the MR department. Some need a small dose of an anxiolytic to be able to undergo the examination. The effect of an anxiolytic on healthy volunteers was evaluated. No effects on the fMRI results was identified but the results were confounded by a large session effect.

    List of papers
    1. Performance of canonical correlation analysis in language tests by functional MRI
    Open this publication in new window or tab >>Performance of canonical correlation analysis in language tests by functional MRI
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a new method based on constraitwd canonical correlation analysis (CCA) for the analysis of fMRI data is evaluated. In particular the method benefits from a powerful way of choosing temporal basis functions in additiou to an adaptive spatial filtering scheme. A modified receiver operating characteristic (ROC) method was used to quantify the results and to compare it with traditionally used statistics in an objective way. The evaluation was performed using real fMRI data form a language test. It was shown that the CCA based method offers a significant gain in detection power.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-97715 (URN)
    Available from: 2013-09-20 Created: 2013-09-20 Last updated: 2014-10-02
    2. Paradigm design of sensory–motor and language tests in clinical fMRI
    Open this publication in new window or tab >>Paradigm design of sensory–motor and language tests in clinical fMRI
    2004 (English)In: Neurophysiologie clinique, ISSN 0987-7053, E-ISSN 1769-7131, Vol. 34, no 6, p. 267-277Article in journal (Refereed) Published
    Abstract [en]

    Functional magnetic resonance imaging (fMRI) paradigms on sensory–motor and language functions are reviewed from a clinical user’s perspective. The objective was to identify special requirements regarding the design of fMRI paradigms for clinical applications. A wide range of methods for setting up fMRI examinations were found in the literature. It was concluded that there is a need for standardised procedures adapted for clinical settings. Sensory–motor activation patterns do not vary much at different hand motion tasks. Nevertheless it is one of the most important clinical tests. In contrast, the language system is much more complex. In several studies it has been observed that word production tasks are preferable in determination of language lateralisation. Broca’s area is activated by most tasks, whereas sentence processing and semantic decision also involve activation in temporoparietal and frontal areas. However, combined task analysis (CTA) of several different tasks has been found to be more robust and reliable for clinical fMRI compared to separate task analysis.

    Abstract [fr]

    Les paradigmes utilisés en Imagerie par Résonance Magnétique fonctionnelle (IRMf) pour l’étude des fonctions sensori-motrice et du langage sont passés en revue du point de vue d’un clinicien. L’objectif était de souligner les exigences spéciales nécessaires à la mise en place d’un paradigme d’IRMf dans le cadre d’études cliniques. Un très grand nombre de procédures pour la réalisation d’examens en IRMf existent dans la littérature. Il a été mis en évidence que la mise en place de procédures standardisées, adaptées aux études cliniques était nécessaire. Les patterns d’activation sensori-motrice ne varient pas plus que les tâches de mouvements de la main. Néanmoins c’est l’un des tests les plus importants en pratique clinique. Au contraire, le système du langage est beaucoup plus complexe. Un grand nombre d’études ont montré que l’utilisation de tâches de production de mots était préférable pour étudier la latéralisation du langage. L’aire de Broca est activée par beaucoup de tâches, alors que le traitement des phrases et la décision sémantique entraînent une activation des aires frontales et temporopariétales. Cependant, dans un contexte d’IRMf clinique, l’analyse des tâches combinées de plusieurs tâches différentes est plus robuste et plus fiable que l’analyse des tâches séparées.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-24683 (URN)10.1016/j.neucli.2004.09.006 (DOI)000228731600002 ()6919 (Local ID)6919 (Archive number)6919 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13
    3. Influence of diazepam on clinically designed FMRI
    Open this publication in new window or tab >>Influence of diazepam on clinically designed FMRI
    Show others...
    2007 (English)In: The Journal of Neuropsychiatry and Clinical Neurosciences, ISSN 0895-0172, E-ISSN 1545-7222, Vol. 19, no 2, p. 164-172Article in journal (Refereed) Published
    Abstract [en]

    The authors investigated the effect of diazepam on clinically relevant measures from functional magnetic resonance imaging (fMRI) examinations. Twenty volunteers were scanned twice. Using a double-blind randomized study design, the volunteers received placebo on one occasion, and on the other, 5 mg of diazepam. Three functional tests were used: motor, word generation, and working memory. Images were analyzed individually for each subject and the number of activated voxels and the laterality index were calculated. No significant effects related to the drug were detected. In contrast, the motor and working memory tasks showed a significant decrease in the number of activated voxels between Sessions 1 and 2, independently of diazepam administration. These results indicate that diazepam may be administered for premedication prior to fMRI investigations.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-17989 (URN)10.1176/appi.neuropsych.19.2.164 (DOI)000245666300009 ()17431063 (PubMedID)
    Available from: 2009-04-30 Created: 2009-04-30 Last updated: 2017-12-13Bibliographically approved
  • 8.
    Ragnehed, Mattias
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Functional Magnetic Resonance Imaging for Clinical Diagnosis: Exploring and Improving the Examination Chain2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Functional Magnetic Resonance Imaging (fMRI) is a relatively new imaging technique, first reported in 1992, which enables mapping of brain functions with high spatial resolution. Functionally active areas are distinguished by a small signal increase mediated by changes in local blood oxygenation in response to neural activity. The ability to non-invasively map brain function and the large number of MRI scanners quickly made the method very popular, and fMRI have had a huge impact on the study of brain function, both in healthy and diseased subjects.

    The most common clinical application of fMRI is pre-surgical mapping of brain functions in order to optimise surgical interventions. The clinical fMRI examination procedure can be divided into four integrated parts: (1) patient preparation, (2) image acquisition, (3) image analysis and (4) clinical decision. In this thesis, important aspects of all parts of the fMRI examination procedure are explored with the aim to provide recommendations and methods for prosperous clinical usage of the technique.

    The most important results of the thesis were: (I) administration of low doses of diazepam to reduce anxiety did not invalidate fMRI mapping results of primary motor and language areas, (II) the choice of visual stimuli equipment can have severe impact on the mapping of visual areas, (III) three-dimensional fMRI imaging sequences did not perform better than two-dimensional imaging sequences, (IV) adaptive spatial filtering can improve the fMRI data analysis, (V) clinical decisions should not be based on activation results from a single statistical threshold.

    List of papers
    1. Influence of diazepam on clinically designed FMRI
    Open this publication in new window or tab >>Influence of diazepam on clinically designed FMRI
    Show others...
    2007 (English)In: The Journal of Neuropsychiatry and Clinical Neurosciences, ISSN 0895-0172, E-ISSN 1545-7222, Vol. 19, no 2, p. 164-172Article in journal (Refereed) Published
    Abstract [en]

    The authors investigated the effect of diazepam on clinically relevant measures from functional magnetic resonance imaging (fMRI) examinations. Twenty volunteers were scanned twice. Using a double-blind randomized study design, the volunteers received placebo on one occasion, and on the other, 5 mg of diazepam. Three functional tests were used: motor, word generation, and working memory. Images were analyzed individually for each subject and the number of activated voxels and the laterality index were calculated. No significant effects related to the drug were detected. In contrast, the motor and working memory tasks showed a significant decrease in the number of activated voxels between Sessions 1 and 2, independently of diazepam administration. These results indicate that diazepam may be administered for premedication prior to fMRI investigations.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-17989 (URN)10.1176/appi.neuropsych.19.2.164 (DOI)000245666300009 ()17431063 (PubMedID)
    Available from: 2009-04-30 Created: 2009-04-30 Last updated: 2017-12-13Bibliographically approved
    2. Projection screen or video goggles as stimulus modality in functional magnetic resonance imaging
    Open this publication in new window or tab >>Projection screen or video goggles as stimulus modality in functional magnetic resonance imaging
    2005 (English)In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 23, no 5, p. 695-699Article in journal (Refereed) Published
    Abstract [en]

    The purpose of this study was to investigate the reliability of functional magnetic resonance imaging (fMRI) by using either a projection screen or video goggles as stimulus modality. A sequence of visual stimuli were presented to the same subject at different occasions. The sequence was optimized with a genetic algorithm. In five sessions the stimuli were presented using a projection screen viewed through a mirror in the head coil and in five sessions using video goggles. Failure to detect visual activation in the medial left hemisphere was observed in sessions using the projection screen as stimulus modality. Decreased thresholds for P values and cluster size resulted in activation outside the occipital lobe and did not significantly increase activated areas in this region. Results in this study indicate that presentation of fMRI tasks with visual routes is more reliable with direct input through video goggles than with the conventional use of projection screens. Failure to detect crucial visual areas has severe consequences for tumor surgery in the visual cortex. Inferior visual impression might also have negative consequences for cognitive tests with high demand on attention and perception.

    Keywords
    fMRI; Visual; Projection screen; Video goggles; Reliability
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-17992 (URN)10.1016/j.mri.2005.04.006 (DOI)16051046 (PubMedID)
    Available from: 2009-04-30 Created: 2009-04-30 Last updated: 2017-12-13Bibliographically approved
    3. Visual Grading of 2D and 3D fMRI compared to image based descriptive measures
    Open this publication in new window or tab >>Visual Grading of 2D and 3D fMRI compared to image based descriptive measures
    Show others...
    2010 (English)In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 20, no 3, p. 714-724Article in journal (Refereed) Published
    Abstract [en]

    A prerequisite for successful clinical use of functional Magnetic Resonance Imaging (fMRI) is the selection of an appropriate imaging sequence. In this paper, 2D and 3D fMRI sequences were compared using different image quality assessment methods. Descriptive image measures, such as activation volume and temporal signal-to-noise ratio (TSNR), were compared with results from Visual Grading Characteristics (VGC) analysis of the fMRI results. It was found that significant differences in activation volume and TSNR were not directly reflected by differences in VGC scores. The results suggest that better performance on descriptive image measures is not always an indicator of improved diagnostic quality of the fMRI results. In conclusion, in addition to descriptive image measures, it is important to include measures of diagnostic quality when comparing different fMRI data acquisition methods.

    Place, publisher, year, edition, pages
    Berlin / Heidelberg: Springer, 2010
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-17994 (URN)10.1007/s00330-009-1578-0 (DOI)000274544800023 ()19727748 (PubMedID)
    Note

    The original publication is available at www.springerlink.com: Mattias Ragnehed, Olof Dahlqvist Leinhard, Johan Pihlsgård, Staffan Wirell, Hannibal Sökjer, Patrik Fägerstam, Bo Jiang, Örjan Smedby, Maria Engström and Peter Lundberg, Visual Grading of 2D and 3D fMRI compared to image based descriptive measures, 2010, European Radiology, (20), 3, 714-724. http://dx.doi.org/10.1007/s00330-009-1578-0 Copyright: Springer Science Business Media http://www.springerlink.com/

    Available from: 2009-04-30 Created: 2009-04-30 Last updated: 2017-12-13Bibliographically approved
    4. Restricted Canonical Correlation Analysis in Functional MRI-Validation and a Novel Thresholding Technique
    Open this publication in new window or tab >>Restricted Canonical Correlation Analysis in Functional MRI-Validation and a Novel Thresholding Technique
    Show others...
    2009 (English)In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 29, no 1, p. 146-154Article in journal (Refereed) Published
    Abstract [en]

    Purpose: To validate the performance of an analysis method for fMRI data based on restricted canonical correlation analysis (rCCA) and adaptive filtering, and to increase the usability of the method by introducing a new technique for significance estimation of rCCA maps.

    Materials and Methods: Activation data from a language task and also a resting state fMRI data were collected from eight volunteers. Data was analyzed using both the rCCA method and the General Linear Model (GLM). A modified Receiver Operating Characteristic (ROC) method was used to evaluate the performance of the different analysis methods. The area under a fraction of the ROC curve was used as a measure of performance. On resting state data the fraction of voxels above certain significance thresholds were used to evaluate the significance estimation method.

    Results: The rCCA method scored significantly higher on the area under the ROC curve than the GLM. The fraction of activated voxels determined by thresholding according to the introduced significance estimation technique showed good agreement with the thresholds selected.

    Conclusion: The rCCA method is an effective analysis tool for fMRI data and its usability is increased with the introduced significance estimation method.

    Keywords
    fMRI, GLM, canonical correlation analysis, thresholding, significance
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-16411 (URN)10.1002/jmri.21494 (DOI)000262168200019 ()
    Available from: 2009-01-23 Created: 2009-01-23 Last updated: 2017-12-14Bibliographically approved
    5. Right-hemispheric brain activation correlates to language performance
    Open this publication in new window or tab >>Right-hemispheric brain activation correlates to language performance
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    2010 (English)In: NEUROIMAGE, ISSN 1053-8119, Vol. 49, no 4, p. 3481-3488Article in journal (Refereed) Published
    Abstract [en]

    Language function in the right-hemispheric homologues of Brocas and Wernickes areas does not only correlate with left-handedness or pathology, but occurs naturally in right-handed healthy subjects as well. In the current study, two non-invasive methods of assessing language lateralization are correlated with behavioral results in order to link hemispheric dominance to language ability in healthy subjects. Functional magnetic resonance imaging (fMRI) together with a sentence-completion paradigm was used to determine region-specific lateralization indices in the left- and right-sided Brocas and Wernickes areas, the frontal temporal lobe, the anterior cingulate cortex and the parietal lobe. In addition, dichotic listening results were used to determine overall language lateralization and to strengthen conclusions by correlating with fMRI indices. Results showed that fMRI lateralization in the superior parietal, the posterior temporal, and the anterior cingulate cortices correlated to dichotic listening. A decreased right ear advantage (REA), which indicates less left- hemispheric dominance in language, correlated with higher performance in most administered language tasks, including reading, language ability, fluency, and non-word discrimination. Furthermore, right hemispheric involvement in the posterior temporal lobe and the homologue of Brocas area suggests better performance in behavioral language tasks. This strongly indicates a supportive role of the right-hemispheric counterparts of Brocas and Wernickes areas in language performance.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-53932 (URN)10.1016/j.neuroimage.2009.10.041 (DOI)000274064500059 ()
    Note
    Original Publication: Helene M van Ettinger-Veenstra, Mattias Ragnehed, Mathias Hällgren, Thomas Karlsson, Anne-Marie Landtblom, Peter Lundberg and Maria Engström, Right-hemispheric brain activation correlates to language performance, 2010, NEUROIMAGE, (49), 4, 3481-3488. http://dx.doi.org/10.1016/j.neuroimage.2009.10.041 Copyright: Elsevier Science B.V., Amsterdam http://www.elsevier.com/Available from: 2010-02-12 Created: 2010-02-12 Last updated: 2014-10-02
  • 9.
    Ragnehed, Mattias
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Dahlqvist Leinhard, Olof
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Pihlsgård, Johan
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Wirell, Staffan
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Sökjer, Hannibal
    Linköping University, Department of Computer and Information Science, MDI - Interaction and Service Design Research Group. Linköping University, The Institute of Technology.
    Fägerstam, Patrik
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Jiang, Bo
    Linköping University, Department of Medical and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Engström, Maria
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Visual Grading of 2D and 3D fMRI compared to image based descriptive measures2010In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 20, no 3, p. 714-724Article in journal (Refereed)
    Abstract [en]

    A prerequisite for successful clinical use of functional Magnetic Resonance Imaging (fMRI) is the selection of an appropriate imaging sequence. In this paper, 2D and 3D fMRI sequences were compared using different image quality assessment methods. Descriptive image measures, such as activation volume and temporal signal-to-noise ratio (TSNR), were compared with results from Visual Grading Characteristics (VGC) analysis of the fMRI results. It was found that significant differences in activation volume and TSNR were not directly reflected by differences in VGC scores. The results suggest that better performance on descriptive image measures is not always an indicator of improved diagnostic quality of the fMRI results. In conclusion, in addition to descriptive image measures, it is important to include measures of diagnostic quality when comparing different fMRI data acquisition methods.

  • 10.
    Ragnehed, Mattias
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Engström, Maria
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Knutsson, Hans
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation. Linköping University, The Institute of Technology.
    Axelsson Söderfeldt, Birgitta
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Clinical and Experimental Medicine, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Restricted Canonical Correlation Analysis in Functional MRI-Validation and a Novel Thresholding Technique2009In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 29, no 1, p. 146-154Article in journal (Refereed)
    Abstract [en]

    Purpose: To validate the performance of an analysis method for fMRI data based on restricted canonical correlation analysis (rCCA) and adaptive filtering, and to increase the usability of the method by introducing a new technique for significance estimation of rCCA maps.

    Materials and Methods: Activation data from a language task and also a resting state fMRI data were collected from eight volunteers. Data was analyzed using both the rCCA method and the General Linear Model (GLM). A modified Receiver Operating Characteristic (ROC) method was used to evaluate the performance of the different analysis methods. The area under a fraction of the ROC curve was used as a measure of performance. On resting state data the fraction of voxels above certain significance thresholds were used to evaluate the significance estimation method.

    Results: The rCCA method scored significantly higher on the area under the ROC curve than the GLM. The fraction of activated voxels determined by thresholding according to the introduced significance estimation technique showed good agreement with the thresholds selected.

    Conclusion: The rCCA method is an effective analysis tool for fMRI data and its usability is increased with the introduced significance estimation method.

  • 11.
    Ragnehed, Mattias
    et al.
    Linköping University, Department of Medicine and Care, Radiology. Linköping University, Faculty of Health Sciences.
    Engström, Maria
    Linköping University, Department of Medicine and Care, Center for Medical Image Science and Visualization. Linköping University, Faculty of Health Sciences.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Department of Medicine and Care, Radiation Physics. Linköping University, Faculty of Health Sciences.
    Söderfeldt, Birgitta
    Linköping University, Department of Neuroscience and Locomotion. Linköping University, Faculty of Health Sciences.
    Performance of canonical correlation analysis in language tests by functional MRIManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a new method based on constraitwd canonical correlation analysis (CCA) for the analysis of fMRI data is evaluated. In particular the method benefits from a powerful way of choosing temporal basis functions in additiou to an adaptive spatial filtering scheme. A modified receiver operating characteristic (ROC) method was used to quantify the results and to compare it with traditionally used statistics in an objective way. The evaluation was performed using real fMRI data form a language test. It was shown that the CCA based method offers a significant gain in detection power.

  • 12.
    Ragnehed, Mattias
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Linköping University, Faculty of Health Sciences.
    Engström, Maria
    Linköping University, Department of Medicine and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Does diazepam influence the BOLD response?2007Conference paper (Other academic)
  • 13.
    Ragnehed, Mattias
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Friman, Ola
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology.
    Söderfeldt, Birgitta
    Linköping University, Department of Neuroscience and Locomotion, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Comparing CCA and SPM992003Conference paper (Refereed)
  • 14.
    Ragnehed, Mattias
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Håkansson, Irene
    Nilsson, Maritha
    Lundberg, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiation Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Söderfeldt, Birgitta
    Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Engström, Maria
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Influence of Diazepam on clinically designed fMRI2006In: American Neuropsyciatric Association annual meeting,2006, 2006Conference paper (Other academic)
  • 15.
    Ragnehed, Mattias
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Health Sciences.
    Håkansson, Irene
    Linköping University, Department of Neuroscience and Locomotion. Linköping University, Faculty of Health Sciences.
    Nilsson, Maritha
    National Board of Forensic Sciences, Linköping.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Söderfeldt, Birgitta
    Department of Clinical Science and Education, Sodersjukhuset, Karolinska Institutet, Stockholm, Sweden.
    Engström, Maria
    Linköping University, Department of Biomedical Engineering, Center for Medical Image Science and Visualization. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Influence of diazepam on clinically designed FMRI2007In: The Journal of Neuropsychiatry and Clinical Neurosciences, ISSN 0895-0172, E-ISSN 1545-7222, Vol. 19, no 2, p. 164-172Article in journal (Refereed)
    Abstract [en]

    The authors investigated the effect of diazepam on clinically relevant measures from functional magnetic resonance imaging (fMRI) examinations. Twenty volunteers were scanned twice. Using a double-blind randomized study design, the volunteers received placebo on one occasion, and on the other, 5 mg of diazepam. Three functional tests were used: motor, word generation, and working memory. Images were analyzed individually for each subject and the number of activated voxels and the laterality index were calculated. No significant effects related to the drug were detected. In contrast, the motor and working memory tasks showed a significant decrease in the number of activated voxels between Sessions 1 and 2, independently of diazepam administration. These results indicate that diazepam may be administered for premedication prior to fMRI investigations.

  • 16.
    Ragnehed, Mattias
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Linköping University, Faculty of Health Sciences.
    Philsgård, J
    Dahlqvist Leinhard, Olof
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Engström, Maria
    Linköping University, Department of Medicine and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Using Visual Grading Characteristic for the evaluation of different fMRI data acquisition methods2008Conference paper (Other academic)
  • 17.
    Smedby, Örjan
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Ragnehed, Mattias
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Medical Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Knutsson, A
    Jacobsson, L
    Yuan, X
    Andersson, R
    Quantitation of atherosclerosis in a minipig model with MRI and dynamic contours2004In: Society of Cardiovascular Magnetic Resonance,2004, 2004Conference paper (Other academic)
  • 18.
    Söderfeldt, Birgitta
    et al.
    Karolinska institutet.
    Ragnehed, Mattias
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Linköping University, Faculty of Health Sciences.
    Håkansson, Irene
    Östergötlands Läns Landsting, Sinnescentrum. Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiation Physics. Linköping University, Department of Medicine and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping. Linköping University, Faculty of Health Sciences.
    Nilsson, M
    Ahlner, Johan
    Östergötlands Läns Landsting, Heart and Medicine Centre. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Endocrinology and Gastroenterology UHL. Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Engström, Maria
    Linköping University, Department of Medicine and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Faculty of Health Sciences.
    Influence of Diazepam on Clinically Designed fMRI2006Conference paper (Other academic)
  • 19.
    van Ettinger-Veenstra, Helene M
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Ragnehed, Mattias
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Hällgren, Mathias
    Linköping University, Department of Clinical and Experimental Medicine, Technical Audiology. Linköping University, Faculty of Health Sciences.
    Karlsson, Thomas
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Arts and Sciences. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Landtblom, Anne-Marie
    Linköping University, Department of Clinical and Experimental Medicine, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Department of Medical Specialist. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology in Linköping.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Right-hemispheric brain activation correlates to language performance2010In: NEUROIMAGE, ISSN 1053-8119, Vol. 49, no 4, p. 3481-3488Article in journal (Refereed)
    Abstract [en]

    Language function in the right-hemispheric homologues of Brocas and Wernickes areas does not only correlate with left-handedness or pathology, but occurs naturally in right-handed healthy subjects as well. In the current study, two non-invasive methods of assessing language lateralization are correlated with behavioral results in order to link hemispheric dominance to language ability in healthy subjects. Functional magnetic resonance imaging (fMRI) together with a sentence-completion paradigm was used to determine region-specific lateralization indices in the left- and right-sided Brocas and Wernickes areas, the frontal temporal lobe, the anterior cingulate cortex and the parietal lobe. In addition, dichotic listening results were used to determine overall language lateralization and to strengthen conclusions by correlating with fMRI indices. Results showed that fMRI lateralization in the superior parietal, the posterior temporal, and the anterior cingulate cortices correlated to dichotic listening. A decreased right ear advantage (REA), which indicates less left- hemispheric dominance in language, correlated with higher performance in most administered language tasks, including reading, language ability, fluency, and non-word discrimination. Furthermore, right hemispheric involvement in the posterior temporal lobe and the homologue of Brocas area suggests better performance in behavioral language tasks. This strongly indicates a supportive role of the right-hemispheric counterparts of Brocas and Wernickes areas in language performance.

  • 20.
    van Ettinger-Veenstra, Helene
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Ragnehed, Mattias
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL.
    McAllister, Anita
    Linköping University, Department of Clinical and Experimental Medicine, Speech and Language Pathology. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping.
    Engström, Maria
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Right-hemispheric cortical contributions to language ability in healthy adults2012In: Brain and Language, ISSN 0093-934X, E-ISSN 1090-2155, Vol. 120, no 3, p. 395-400Article in journal (Refereed)
    Abstract [en]

    In this study we investigated the correlation between individual linguistic ability based on performance levels and their engagement of typical and atypical language areas in the brain. Eighteen healthy subjects between 21 and 64 years participated in language ability tests, and subsequent functional MRI scans measuring brain activity in response to a sentence completion and a word fluency task. Performance in both reading and high-level language tests correlated positively with increased right-hemispheric activation in the inferior frontal gyrus (specifically Brodmann area 47), the dorsolateral prefrontal cortex (DLPFC), and the medial temporal gyrus (Brodmann area 21). In contrast, we found a negative correlation between performance and left-hemispheric DLPFC activation.

    Our findings indicate that the right lateral frontal and right temporal regions positively modulate aspects of language ability.

1 - 20 of 20
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