Open AccessImpact of scale space search on age‐ and gender‐related changes in MRI‐based cortical morphometry
Author(s) -
Zhao Lu,
Boucher Maxime,
RosaNeto Pedro,
Evans Alan C.
Publication year - 2013
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.22050
Subject(s) - scale space , smoothing , scale (ratio) , gaussian blur , filter (signal processing) , space (punctuation) , population , artificial intelligence , magnetic resonance imaging , pattern recognition (psychology) , mathematics , computer science , statistics , computer vision , medicine , radiology , geography , image processing , cartography , environmental health , image (mathematics) , image restoration , operating system
In magnetic resonance imaging based brain morphometry, Gaussian smoothing is often applied to increase the signal‐to‐noise ratio and to increase the detection power of statistical parametric maps. However, most existing studies used a single smoothing filter without adequately justifying their choices. In this article, we want to determine the extent for which performing a morphometry analysis using multiple smoothing filters, namely conducting a scale space search, improves or decreases the detection power. We first compared scale space search with single‐filter analysis through a simulated population study. The multiple comparisons in our four‐dimensional scale space searches were corrected for using a unified P ‐value approach. Our results illustrate that, compared with a single‐filter analysis, a scale space search analysis can properly capture the variations in analysis results caused by variations in smoothing, and more importantly, it can obviously increase the sensitivity for detecting brain morphometric changes. We also show that the cost of an increased critical threshold for conducting a scale space search is very small. In the second experiment, we investigated age and gender effects on cortical volume, thickness, and surface area in 104 normal subjects using scale space search. The obtained results provide a perspective of scale space theory on the morphological changes with age and gender. These results suggest that, in exploratory studies of aging, gender, and disease, conducting a scale space search is essential, if we are to produce a complete description of the structural changes or abnormalities associated with these dimensions. Hum Brain Mapp 34:2113–2128, 2013 . © 2011 Wiley Periodicals, Inc.