Premium
Functional mapping of the human visual cortex at 4 and 1.5 tesla using deoxygenation contrast EPI
Author(s) -
Turner R.,
Jezzard P.,
Wen H.,
Kwong K. K.,
Le Bihan D.,
Zeffiro T.,
Balaban R. S.
Publication year - 1993
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.1910290221
Subject(s) - deoxygenation , visual cortex , nuclear magnetic resonance , contrast (vision) , cortex (anatomy) , blood oxygenation , oxygenation , human brain , deoxygenated hemoglobin , chemistry , physics , neuroscience , functional magnetic resonance imaging , medicine , optics , biology , hemoglobin , biochemistry , catalysis
The effects of photic stimulation on the visual cortex of human brain were studied by means of gradient‐echo echo‐planar imaging (EPI). Whole‐body 4 and 1.5 T MRI systems, equipped with a small z axis head gradient coil, were used. Variations of image intensity of up to 28% at 4 T, and up to 7% at 1.5 T, were observed in primary visual cortex, corresponding to an increase of blood oxygenation in regions of increased neural activity. The larger effects at 4 T are due to the increased importance of the susceptibility difference between deoxy‐genated and oxygenated blood at high fields.