Title
Genetics of anisotropy asymmetry: registration and sample size effects.
Abstract
Brain asymmetry has been a topic of interest for neuroscientists for many years. The advent of diffusion tensor imaging (DTI) allows researchers to extend the study of asymmetry to a microscopic scale by examining fiber integrity differences across hemispheres rather than the macroscopic differences in shape or structure volumes. Even so, the power to detect these microarchitectural differences depends on the sample size and how the brain images are registered and how many subjects are studied. We fluidly registered 4 Tesla DTI scans from 180 healthy adult twins (45 identical and fraternal pairs) to a geometrically-centered population mean template. We computed voxelwise maps of significant asymmetries (left/right hemisphere differences) for common fiber anisotropy indices (FA, GA). Quantitative genetic models revealed that 47-62% of the variance in asymmetry was due to genetic differences in the population. We studied how these heritability estimates varied with the type of registration target (T1- or T2-weighted) and with sample size. All methods consistently found that genetic factors strongly determined the lateralization of fiber anisotropy, facilitating the quest for specific genes that might influence brain asymmetry and fiber integrity.
Year
DOI
Venue
2009
10.1007/978-3-642-04271-3_61
MICCAI
Keywords
Field
DocType
fiber anisotropy,brain asymmetry,brain image,fiber integrity,anisotropy asymmetry,significant asymmetry,genetic difference,sample size,common fiber anisotropy index,fiber integrity difference,genetic factor,genetics,quantitative genetics,brain imaging
Population,Diffusion MRI,Computer science,Artificial intelligence,Asymmetry,Pathology,Brain asymmetry,Heritability,Lateralization of brain function,Pattern recognition,Fractional anisotropy,Nuclear magnetic resonance,Sample size determination
Conference
Volume
Issue
ISSN
12
Pt 2
0302-9743
Citations 
PageRank 
References 
1
0.37
5
Authors
11
Name
Order
Citations
PageRank
Neda Jahanshad133642.81
Agatha D Lee229623.02
Natasha Leporé312211.23
Yi-Yu Chou429022.25
Caroline C. Brun5936.42
Marina Barysheva626922.02
Arthur W. Toga73128261.46
Katie L. Mcmahon837433.49
Greig I de Zubicaray9695.31
Margaret J. Wright1043639.31
Paul Thompson113860321.32