Please use this identifier to cite or link to this item: http://ahro.austin.org.au/austinjspui/handle/1/10956
Title: fMRI assessment of language lateralization: an objective approach.
Authors: Abbott, David F;Waites, Anthony B;Lillywhite, Leasha M;Jackson, Graeme D
Affiliation: Brain Research Institute, Florey Neuroscience Institutes (Austin), Melbourne, Victoria, Australia.
Issue Date: 22-Jan-2010
Citation: Neuroimage 2010; 50(4): 1446-55
Abstract: Language lateralization based on functional magnetic resonance imaging (fMRI) is often used in clinical neurological settings. Currently, interpretation of the distribution, pattern and extent of language activation can be heavily dependent on the chosen statistical threshold. The aim of the present study was to 1) test the robustness of adaptive thresholding of fMRI data to yield a fixed number of active voxels, and to 2) develop a largely threshold-independent method of assessing when individual patients have statistically atypical language lateralization. Simulated data and real fMRI data in 34 healthy controls and 4 selected epilepsy patients performing a verbal fluency language fMRI task were used. Dependence of laterality on the thresholding method is demonstrated for simulated and real data. Simulated data were used to test the hypothesis that thresholding based upon a fixed number of active voxels would yield a laterality index that was more stable across a range of signal strengths (study power) compared to thresholding at a fixed p value. This stability allowed development of a method comparing an individual to a group of controls across a wide range of thresholds, providing a robust indication of atypical lateralization that is more objective than conventional methods. Thirty healthy controls were used as normative data for the threshold-independent method, and the remaining subjects were used as illustrative examples. The method could also be used more generally to assess relative regional distribution of activity in other neuroimaging paradigms (for example, one could apply it to the assessment of lateralization of activation in a memory task, or to the assessment of anterior-posterior distribution rather than laterality).
Internal ID Number: 20097290
URI: http://ahro.austin.org.au/austinjspui/handle/1/10956
DOI: 10.1016/j.neuroimage.2010.01.059
URL: http://www.ncbi.nlm.nih.gov/pubmed/20097290
Type: Journal Article
Subjects: Adolescent
Adult
Aged
Brain.physiology.physiopathology
Child
Computer Simulation
Epilepsy.diagnosis.physiopathology
Functional Laterality
Humans
Language
Language Disorders.diagnosis.physiopathology
Magnetic Resonance Imaging.methods
Middle Aged
Signal Processing, Computer-Assisted
Young Adult
Appears in Collections:Journal articles

Files in This Item:
There are no files associated with this item.


Items in AHRO are protected by copyright, with all rights reserved, unless otherwise indicated.