Connectivity exploration with structural equation modeling: an fMRI study of bimanual motor coordination.
The present fMRI study explores the connectivity among motor areas in a bimanual coordination task using the analysis framework of structural equation modeling (SEM). During bimanual finger tapping at different frequency ratios, temporal correlations of activations between left/right primary motor cortices (MI), left/right PMdc (caudal dorsal premotor area) and supplementary motor cortex (SMA) were detected and used as inputs to the SEM analysis. SEM was extended from its traditional role as a confirmatory analysis to be used as an exploratory technique to determine the most statistically significant connectivity model given a set of cortical areas based on anatomic constraints. The resultant network exhibits coupling from left MI to right MI, links from both PMs to the two MIs, a negative interaction from left PM to right PM, and functional influence from SMA to right MI and right PM, revealing contributions of these areas to bimanual coordination.
Zhuang
Jiancheng
J
Biomedical Imaging Technology Center, Department of Biomedical Engineering, Emory University/Georgia Institute of Technology, 1639 Pierce Drive, Suite 2001, Atlanta, GA 30322, USA.
LaConte
Stephen
S
Peltier
Scott
S
Zhang
Kan
K
Hu
Xiaoping
X
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000502:physiology*; D005260:Female; D006225:Hand / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015233:Models, Statistical; D009043:Motor Activity / Q000502:physiology*