fMRI activation in a visual-perception task: Network of areas detected using the general linear model and independent components analysis

Citation
Vd. Calhoun et al., fMRI activation in a visual-perception task: Network of areas detected using the general linear model and independent components analysis, NEUROIMAGE, 14(5), 2001, pp. 1080-1088
Citations number
32
Categorie Soggetti
Neurosciences & Behavoir
Journal title
NEUROIMAGE
ISSN journal
10538119 → ACNP
Volume
14
Issue
5
Year of publication
2001
Pages
1080 - 1088
Database
ISI
SICI code
1053-8119(200111)14:5<1080:FAIAVT>2.0.ZU;2-M
Abstract
The Motor-Free Visual Perception Test, revised (MVPT-R), provides a measure of visual perceptual processing. It involves different cognitive elements including visual discrimination, spatial relationships, and mental rotation . We adapted the MVPT-R to an event-related functional AM (fMRI) environmen t to investigate the brain regions involved in the interrelation of these c ognitive elements. Two complementary analysis methods were employed to char acterize the fMRI data: (a) a general linear model SPM approach based upon a model of the time course and a hemodynamic response estimate and (b) inde pendent component analysis (ICA), which does not constrain the specific sha pe of the time course per se, although we did require it to be at least tra nsiently task-related. Additionally, we implemented ICA in a novel way to c reate a group average that was compared with the SPM group results. Both me thods yielded similar, but not identical, results and detected a network of robustly activated visual, inferior parietal, and frontal eye-field areas as well as thalamus and cerebellum. SPM appeared to be the more sensitive m ethod and has a well-developed theoretical approach to thresholding. The IC A method segregated functional elements into separate maps and identified a dditional regions with extended activation in response to presented events. The results demonstrate the utility of complementary analyses for fMRI dat a and suggest that the cerebellum may play a significant role in visual per ceptual processing. Additionally, results illustrate functional connectivit y between frontal eye fields and prefrontal and parietal regions. (C) 2001 Academic Press.