LI-tool: A new toolbox to assess lateralization in functional MR-data

A lateralization index (LI) is commonly computed to describe the asymmetry of activation as detectable by various functional imaging techniques, particularly functional magnetic resonance imaging (fMRI). In this article, we examine and compare different approaches that have been used in the past. For illustration purposes, 100 synthetic datasets and real fMRI-data from 12 subjects were evaluated. As shown before, the calculation of a lateralization index suffers from a number of drawbacks, namely vulnerability to statistical outliers, data sparsity, thresholding effects and lack of taking into account regional variability of activation. Optional processing steps investigated here seem to increase reliability of the such-calculated indices. To allow a more standardized, reproducible and accessible evaluation of laterality effects, current and new approaches have been implemented in a versatile toolbox running within the spm2 or spm5 software environment.

[1]  R W Cox,et al.  Real‐time 3D image registration for functional MRI , 1999, Magnetic resonance in medicine.

[2]  Thomas E. Nichols,et al.  Nonparametric permutation tests for functional neuroimaging: A primer with examples , 2002, Human brain mapping.

[3]  Thomas E. Nichols,et al.  Combining voxel intensity and cluster extent with permutation test framework , 2004, NeuroImage.

[4]  S. Sato,et al.  Language dominance in partial epilepsy patients identified with an fMRI reading task , 2002, Neurology.

[5]  Wolfgang Grodd,et al.  Lesion-induced right-hemispheric language and organization of nonverbal functions , 2006, Neuroreport.

[6]  Karl J. Friston,et al.  Modelling Geometric Deformations in Epi Time Series , 2022 .

[7]  Marko Wilke,et al.  Bright spots: correlations of gray matter volume with IQ in a normal pediatric population , 2003, NeuroImage.

[8]  J. E Adcock,et al.  Quantitative fMRI assessment of the differences in lateralization of language-related brain activation in patients with temporal lobe epilepsy , 2003, NeuroImage.

[9]  Jos B. T. M. Roerdink,et al.  Denoising functional MR images: a comparison of wavelet denoising and Gaussian smoothing , 2004, IEEE Transactions on Medical Imaging.

[10]  A Thron,et al.  MR blood oxygenation level-dependent signal differences in parenchymal and large draining vessels: implications for functional MR imaging. , 1999, AJNR. American journal of neuroradiology.

[11]  Karl J. Friston,et al.  Assessing the significance of focal activations using their spatial extent , 1994, Human brain mapping.

[12]  N. Tzourio-Mazoyer,et al.  Automated Anatomical Labeling of Activations in SPM Using a Macroscopic Anatomical Parcellation of the MNI MRI Single-Subject Brain , 2002, NeuroImage.

[13]  D. Gadian,et al.  Language reorganization in children with early-onset lesions of the left hemisphere: an fMRI study. , 2004, Brain : a journal of neurology.

[14]  Karl J. Friston,et al.  A unified statistical approach for determining significant signals in images of cerebral activation , 1996, Human brain mapping.

[15]  V. Schmithorst,et al.  Normal fMRI Brain Activation Patterns in Children Performing a Verb Generation Task , 2001, NeuroImage.

[16]  F Crivello,et al.  Interindividual variability in the hemispheric organization for speech , 2004, NeuroImage.

[17]  Katrin Amunts,et al.  Broca's region: Cytoarchitectonic asymmetry and developmental changes , 2003, The Journal of comparative neurology.

[18]  Karl J. Friston,et al.  Variational Bayesian inference for fMRI time series , 2003, NeuroImage.

[19]  Jonathan Marchini,et al.  Comparing methods of analyzing fMRI statistical parametric maps , 2004, NeuroImage.

[20]  Karl J. Friston,et al.  Incorporating Prior Knowledge into Image Registration , 1997, NeuroImage.

[21]  R. C. Oldfield The assessment and analysis of handedness: the Edinburgh inventory. , 1971, Neuropsychologia.

[22]  Stefan Knecht,et al.  How atypical is atypical language dominance? , 2003, NeuroImage.

[23]  J Mazziotta,et al.  A probabilistic atlas and reference system for the human brain: International Consortium for Brain Mapping (ICBM). , 2001, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[24]  C. Price The anatomy of language: contributions from functional neuroimaging , 2000, Journal of anatomy.

[25]  Richard J. Davidson,et al.  The asymmetrical brain , 2003 .

[26]  M Erb,et al.  Early left periventricular brain lesions induce right hemispheric organization of speech , 2001, Neurology.

[27]  J. Kuratsu,et al.  Method for quantitatively evaluating the lateralization of linguistic function using functional MR imaging. , 2001, AJNR. American journal of neuroradiology.

[28]  Thomas E. Nichols,et al.  Controlling the familywise error rate in functional neuroimaging: a comparative review , 2003, Statistical methods in medical research.

[29]  G. Vingerhoets,et al.  MRI language dominance assessment in epilepsy patients at 1.0 T: region of interest analysis and comparison with intracarotid amytal testing , 2004, Neuroradiology.