Title
Anatomically informed interpolation of fMRI data on the cortical surface.
Abstract
Analyzing functional magnetic resonance imaging (fMRI) data restricted to the cortical surface is of particular interest for two reasons: (1) to increase detection sensitivity using anatomical constraints and (2) to compare or use fMRI results in the context of source localization from magneto/electro-encephalography (MEEG) data, which requires data to be projected on the same spatial support. Designing an optimal scheme to interpolate fMRI raw data or resulting activation maps on the cortical surface relies on a trade-off between choosing large enough interpolation kernels, because of the distributed nature of the hemodynamic response, and avoiding mixing data issued from different anatomical structures. We propose an original method that automatically adjusts the level of such a trade-off, by defining interpolation kernels around each vertex of the cortical surface using a geodesic Voronoï diagram. This Voronoï-based interpolation method was evaluated using simulated fMRI activation maps, manually generated on an anatomical MRI, and compared with a more standard approach where interpolation kernels were defined as local spheres of radius r=3 or 5 mm. Several validation parameters were considered: the spatial resolution of the simulated activation map, the spatial resolution of the cortical mesh, the level of anatomical/functional data misregistration and the location of the vertices within the gray matter ribbon. Using an activation map at the spatial resolution of standard fMRI data, robustness to misregistration errors was observed for both methods, whereas only the Voronoï-based approach was insensitive to the position of the vertices within the gray matter ribbon.
Year
DOI
Venue
2006
10.1016/j.neuroimage.2006.02.049
NeuroImage
Keywords
Field
DocType
fMRI,Anatomical constraints,Cortical surface,Voronoï diagram
Interpolation,Cognitive psychology,Robustness (computer science),Voronoi diagram,Artificial intelligence,Computer vision,Pattern recognition,Vertex (geometry),Functional magnetic resonance imaging,Anatomical structures,Image resolution,Mathematics,Geodesic
Journal
Volume
Issue
ISSN
31
4
1053-8119
Citations 
PageRank 
References 
14
1.42
9
Authors
6
Name
Order
Citations
PageRank
C. Grova1927.44
S Makni2141.42
G Flandin312111.39
P. Ciuciu4996.15
Jean Gotman524520.25
J B Poline6141.42