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An Model for Stimulus-Related Signal Changes in Diffusion-Weighted fMRI
https://repo.qst.go.jp/records/62037
https://repo.qst.go.jp/records/62037c4ca673d-4219-4b9a-a23b-019bca031c74
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2007-03-23 | |||||
| タイトル | ||||||
| タイトル | An Model for Stimulus-Related Signal Changes in Diffusion-Weighted fMRI | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
| 資源タイプ | conference object | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
Kershaw, Jeffrey
× Kershaw, Jeffrey× Tomiyasu, Moyoko× Kashikura, Kenichi× Hirano, Yoshiyuki× Nonaka, Hiroi× Ikehira, Hiroo× Kanno, Iwao× Obata, Takayuki× et.al× Ｋｅｒｓｈａｗ Ｊｅｆｆｒｅｙ× 富安 もよこ× 柏倉 健一× 平野 好幸× 野中 博意× 池平 博夫× 菅野 巖× 小畠 隆行 |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | Intro: A model is proposed for the stimulus-induced signal change in diffusion-weighted (DW) fMRI. Theory: Signal from brain during fMRI experiments may be broken down into intravascular (IV) and extravascular (EV) parts: S(t,b)=SIV(t,b)+SEV(t,b), with the IV signal often removed by mild DW (b~50-250 s/mm2). It is proposed that the EV signal in SE-BOLD DW fMRI may be further decomposed into distinct contributions from a fast- (FDP) and a slow-diffusion phase (SDP): SEV(t,b) = Sf(t) exp(-b Df)+Ss(t) exp(-b Ds). Time-dependence of the EV signal is entirely contained in Sf(t) and Ss(t), reflecting the independence of transverse relaxation in the EV compartments. It is assumed that Df and Ds are much less than the apparent diffusion coefficient of the IV compartment. Methods: A visual stimulation study was conducted on 8 volunteers (7M/1F, 20-31 years). Experiments were performed on a whole-body 3T MRI system. DW images (b=0, 200, 1400 s/mm2) were obtained with a spin-echo EPI sequence sensitized to diffusion. Results: The stimulus-induced signal changes were decomposed into IV, SDP and FDP contributions. The SDP time-course had no post-stimulus undershoot, suggesting that the large EV undershoot originates from the FDP alone. Also, the SDP contribution shows a positive deflection highly correlated with the stimulation, implying that it closely reflects the neural response without contamination by the undershoot. The physical nature of the FDP and SDP compartments is still obscure, however the SDP and FDP time-courses may be related to BOLD or activity-induced cell swelling. | |||||
| 会議概要（会議名, 開催地, 会期, 主催者等） | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | 第9回日本ヒト脳機能マッピング学会大会 | |||||
| 発表年月日 | ||||||
| 日付 | 2007-03-17 | |||||
| 日付タイプ | Issued | |||||
