Linked Life Data

7760717

Source:http://linkedlifedata.com/resource/pubmed/id/7760717

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-6-23
pubmed:abstractText
We show that the EPI time course in functional MR imaging at 4 Tesla displays a multiphasic response in response to photic stimulation. Focal areas of gray matter display an initial negative change in signal intensity that reaches a maximum of 1% about 2 s after the onset of photic stimulation. This component then changes sign, reaching a positive maximum about 5 s after the onset of the stimulus. Other areas, including those where draining veins are visible, show only a positive signal change, reaching a maximum of about 6% after the onset of the visual stimulus. These time constants are in very good agreement with published data obtained with intrinsic optical mapping techniques, where a deoxygenation phase has been shown to occur in functionally specific cortical columns, followed by an increase in blood volume which is more distributed in nature. Thus, we believe there is strong evidence that a sensitivity to capillary oxygenation state is present in high S/N functional MR images obtained with EPI at 4 T.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0740-3194
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
453-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
BOLD based functional MRI at 4 Tesla includes a capillary bed contribution: echo-planar imaging correlates with previous optical imaging using intrinsic signals.
pubmed:affiliation
John P. Robarts Research Institute, Advanced Imaging Group, London, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't