Title
Increased sensitivity in mapping task demand in visuospatial processing using reaction-time-dependent hemodynamic response predictors in rapid event-related fMRI.
Abstract
Searching for the neural correlates of visuospatial processing using functional magnetic resonance imaging (fMRI) is usually done in an event-related framework of cognitive subtraction, applying a paradigm comprising visuospatial cognitive components and a corresponding control task. Besides methodological caveats of the cognitive subtraction approach, the standard general linear model with fixed hemodynamic response predictors bears the risk of being underspecified. It does not take into account the variability of the blood oxygen level-dependent signal response due to variable task demand and performance on the level of each single trial. This underspecification may result in reduced sensitivity regarding the identification of task-related brain regions. In a rapid event-related fMRI study, we used an extended general linear model including single-trial reaction-time-dependent hemodynamic response predictors for the analysis of an angle discrimination task. In addition to the already known regions in superior and inferior parietal lobule, mapping the reaction-time-dependent hemodynamic response predictor revealed a more specific network including task demand-dependent regions not being detectable using the cognitive subtraction method, such as bilateral caudate nucleus and insula, right inferior frontal gyrus and left precentral gyrus.
Year
DOI
Venue
2006
10.1016/j.neuroimage.2005.12.064
NeuroImage
Keywords
Field
DocType
SPL,IPL,IFG,GPrC,MOG,SOG,Caudate Ncl
Caudate nucleus,Insula,Neural correlates of consciousness,Developmental psychology,Functional magnetic resonance imaging,General linear model,Inferior parietal lobule,Psychology,Cognitive psychology,Cognition,Subtraction
Journal
Volume
Issue
ISSN
31
2
1053-8119
Citations 
PageRank 
References 
4
0.48
4
Authors
5
Name
Order
Citations
PageRank
Christoph Lehmann140.48
Patrizia Vannini2152.61
Lars-Olof Wahlund3615.68
Ove Almkvist4141.65
Thomas Dierks5507.16