Negative BOLD in the visual cortex: Evidence against blood stealing
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چکیده
منابع مشابه
Negative BOLD in the visual cortex: evidence against blood stealing.
The positive BOLD (blood oxygen level-dependent) response elicited in human visual cortex by a localized visual stimulus is accompanied by a reduction in the BOLD response in regions of the visual cortex that represent unstimulated locations in the visual field. We have suggested previously that this negative BOLD reflects attention-related suppression of neural activity, but it might also be e...
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Sustained positive BOLD (blood oxygen level-dependent) activity is employed extensively in functional magnetic resonance imaging (fMRI) studies as evidence for task or stimulus-specific neural responses. However, the presence of sustained negative BOLD activity (i.e., sustained responses that are lower than the fixation baseline) has remained more difficult to interpret. Some studies suggest th...
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Recent studies emphasize the overlap between the neural substrates of visual perception and visual imagery. However, the subjective experiences of imagining and seeing are clearly different. Here we demonstrate that deactivation of auditory cortex (and to some extent of somatosensory and subcortical visual structures) as measured by BOLD functional magnetic resonance imaging unequivocally diffe...
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The sustained negative blood oxygenation level-dependent (BOLD) response in functional MRI is observed universally, but its interpretation is controversial. The origin of the negative response is of fundamental importance because it could provide a measurement of neural deactivation. However, a substantial component of the negative response may be due to a non-neural hemodynamic artifact. To di...
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ژورنال
عنوان ژورنال: Human Brain Mapping
سال: 2004
ISSN: 1065-9471,1097-0193
DOI: 10.1002/hbm.20017