抄録
Hemodynamic responses evoked by neural activation are used to visualize active brain areas in various functional brain imaging techniques, such as PET, fMRI and intrinsic signal imaging. Though the major focus of these techniques is spatial localization of the active areas, the spatial precision of hemodynamic responses is not well understood. The purpose of this study was to investigate the spatial precision of hemodynamic responses by using intrinsic signal imaging. In particular, we focused on activity-dependent changes in the blood volume. We visualized sub-millimeter-scale functional structures such as orientation columns in the feline visual cortex using intrinsic signal imaging. To investigate the spatial precision of changes in the blood volume, we extracted the blood volume component from intrinsic signals using the Beer–Lambert equation, and directly visualized changes in the blood volume by observing absorption changes of an extrinsic dye infused into the bloodstream. In both cases, we succeeded in visualizing sub-millimeter-scale functional structures as changes in the blood volume. Taking into account that spatial separation of arteries is coarser than the spatial layout of sub-millimeter-scale functional structures, we believe these results suggest that there are supplementary control mechanisms of blood flow, probably in the capillary beds, in addition to arterial global control.
| 元の言語 | English |
|---|---|
| ページ（範囲） | 165-171 |
| ページ数 | 7 |
| ジャーナル | International Congress Series |
| 巻 | 1235 |
| 発行部数 | C |
| DOI | |
| 出版物ステータス | Published - 2002 7 1 |
| 外部発表 | Yes |
ASJC Scopus subject areas
- Medicine(all)
これを引用
Contribution of blood volume changes to intrinsic optical signals. / Mitsuhiro, Fukuda; Umamaheswari, Rajagopalan; Ryota, Homma; Manabu, Tanifuji.
：: International Congress Series, 巻 1235, 番号 C, 01.07.2002, p. 165-171.研究成果: Article
}
TY - JOUR
T1 - Contribution of blood volume changes to intrinsic optical signals
AU - Mitsuhiro, Fukuda
AU - Umamaheswari, Rajagopalan
AU - Ryota, Homma
AU - Manabu, Tanifuji
PY - 2002/7/1
Y1 - 2002/7/1
N2 - Hemodynamic responses evoked by neural activation are used to visualize active brain areas in various functional brain imaging techniques, such as PET, fMRI and intrinsic signal imaging. Though the major focus of these techniques is spatial localization of the active areas, the spatial precision of hemodynamic responses is not well understood. The purpose of this study was to investigate the spatial precision of hemodynamic responses by using intrinsic signal imaging. In particular, we focused on activity-dependent changes in the blood volume. We visualized sub-millimeter-scale functional structures such as orientation columns in the feline visual cortex using intrinsic signal imaging. To investigate the spatial precision of changes in the blood volume, we extracted the blood volume component from intrinsic signals using the Beer–Lambert equation, and directly visualized changes in the blood volume by observing absorption changes of an extrinsic dye infused into the bloodstream. In both cases, we succeeded in visualizing sub-millimeter-scale functional structures as changes in the blood volume. Taking into account that spatial separation of arteries is coarser than the spatial layout of sub-millimeter-scale functional structures, we believe these results suggest that there are supplementary control mechanisms of blood flow, probably in the capillary beds, in addition to arterial global control.
AB - Hemodynamic responses evoked by neural activation are used to visualize active brain areas in various functional brain imaging techniques, such as PET, fMRI and intrinsic signal imaging. Though the major focus of these techniques is spatial localization of the active areas, the spatial precision of hemodynamic responses is not well understood. The purpose of this study was to investigate the spatial precision of hemodynamic responses by using intrinsic signal imaging. In particular, we focused on activity-dependent changes in the blood volume. We visualized sub-millimeter-scale functional structures such as orientation columns in the feline visual cortex using intrinsic signal imaging. To investigate the spatial precision of changes in the blood volume, we extracted the blood volume component from intrinsic signals using the Beer–Lambert equation, and directly visualized changes in the blood volume by observing absorption changes of an extrinsic dye infused into the bloodstream. In both cases, we succeeded in visualizing sub-millimeter-scale functional structures as changes in the blood volume. Taking into account that spatial separation of arteries is coarser than the spatial layout of sub-millimeter-scale functional structures, we believe these results suggest that there are supplementary control mechanisms of blood flow, probably in the capillary beds, in addition to arterial global control.
KW - Beer–Lambert law
KW - Capillary
KW - Hemodynamic responses
KW - Orientation column
KW - Visual cortex
UR - http://www.scopus.com/inward/record.url?scp=85023088368&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85023088368&partnerID=8YFLogxK
U2 - 10.1016/S0531-5131(02)00183-8
DO - 10.1016/S0531-5131(02)00183-8
M3 - Article
AN - SCOPUS:85023088368
VL - 1235
SP - 165
EP - 171
JO - International Congress Series
JF - International Congress Series
SN - 0531-5131
IS - C
ER -