Brain Star - June 15, 2002
Recipient:
Article :
K.E. Watkins, T. paus, J.P. Lerch, A. Zijdenbos, D. L. Collins, P. Neelin,J. Taylor, K.J. Worsley, C. Evans. (2001)Structural asymmetries in the human brain: a Voxel-based statisticalanalysis of 142 MRI scans, Cerebral Cortex 11: 868-877
Significance of the paper:The hemispheres of the human brain are functionally and structurally asymmetric. The analysis of structural asymmetries aims to elucidate the neuroanatomical basis of lateralized brain functions and of disorders with a presumed developmental neurological basis, such as schizophrenia or dyslexia. With the advent of magnetic resonance imaging, we can obtain high-resolution images of the human brain allowing in vivo studies of anatomy. In this paper, we present an adaptation of a recently developed computerized technique of whole-brain image analysis, which we used to statistically compare the regional amounts of grey matter in the left and right hemispheres of 142 healthy young adults. The analysis of MRI brain volumes uses computer-based spatial transformations to remove differences due to brain size and automated algorithms to classify tissues. The method has many obvious advantages over traditional region-of-interest manual analyses. In addition to replicating the well-known asymmetries between the left and right hemispheres, such as the larger right frontal and left occipital protrusions (or petalias) and the larger left planum temporale, our analysis provided evidence of asymmetries not previously reported, possibly because of difficulties in defining anatomical boundaries. One such highly significant asymmetry was that of a larger right anterior insular cortex. This method has potential application in many areas, for example, the study of populations with clinically defined disorders, in whom it is suspected that abnormal brain development has resulted in atypical structural asymmetries and, in turn, in abnormal functional organization.
