Paper Info
Title
Dopaminergic effects on electrophysiological and functional MRI measures of human cortical stimulus-response power laws.
Abstract
Power laws have been widely used to formulate relationships between objective intensity of stimulation and subjective intensityof sensation. We investigated the effects of dopaminergic drug treatment (sulpiride) on the relationship between somatosensory stimulus intensity and cortical response measured electrophysiologically by somatosensory-evoked potentials (SEP) and functional magnetic resonance imaging (fMRI). The intensity of stimulation was related by a simple power law to both electrophysiological and fMRI measures of cortical response, with overlapping confidence intervals for both power law exponents. Sulpiride did not modulate the power law exponent, but significantly attenuated the “gain” of both stimulus–response functions. Using path analysis we decomposed dopaminergic effects on fMRI data into an indirect component (16%), predictable by drug effects on SEP, and a direct component (84%), not explained electrophysiologically. Results indicate that sulpiride has comparable effects on power law parameters estimated from SEP and fMRI, but fMRI has superior sensitivity to detect drug effects on somatosensory cortical recruitment by graded stimulation.
Year
DOI
Venue
2004
10.1016/j.neuroimage.2003.09.067
NeuroImage
Keywords
DocType
Volume
Dopamine,Psychophysics,Scaling,Path analysis,Somatosensory,Multimodal
Journal
21
Issue
ISSN
Citations 
2
1053-8119
7
PageRank 
References 
Authors
2.83
0
7
Name
Order
Citations
PageRank
O. J. Arthurs172.83
C. M. E. Stephenson272.83
Ken Rice3175.41
V. C. Lupson472.83
David J. Spiegelhalter5340206.59
S. J. Boniface672.83
E. T. Bullmorea772.83