Mapping cortical representations of the rodent forepaw and hindpaw with BOLD fMRI reveals two spatial boundaries.
Mapping cortical representations of the rodent forepaw and hindpaw with BOLD fMRI reveals two spatial boundaries.
复制标题
DOI：
10.1016/j.neuroimage.2011.04.002
复制
发表时间：
2011-07-15
期刊：
影响因子：
5.7
通讯作者：
Koretsky, Alan P.
中科院分区：
文献类型：
--
作者：
Goloshevsky, Artem G.;Wu, Carolyn W. -H.;Dodd, Stephen J.;Koretsky, Alan P.
关键词：
采用电刺激大鼠前爪和后掌的方法，研究BOLD功能磁共振成像的空间分布。多次功能磁共振成像会话的平均显著提高了BOLD信号的空间稳定性，并使BOLD功能磁共振图的边界得以定量确定。平均的BOLD fMRI信号在地图的范围内分布不均匀，边界上的数据可以用主要和次要的空间成分来建模。在各向同性300μm分辨率的三维回波平面成像功能磁共振成像中，BOLD信号的主要空间分量的边界位置在前爪和后掌图上不重叠。有趣的是，较小的粗体fMRI空间分量的边界位置显著扩展到相邻表示。使用氧化铁颗粒获得的脑血容量(CBV)加权fMRI也发现了类似的结果，这表明微小的空间成分可能不是由于通常与BOLD fMRI相关的血管定位错误所致。将前爪和后掌的BOLD fMRI图与细胞色素氧化酶(CO)染色的组织学结果进行比较，表明BOLD fMRI图的主要空间成分准确地定位了边界。最后，在周围神经失神经后2-3周，研究了成年大鼠脑内躯体感觉肢体表征边界的皮质重组/可塑性。后爪失神经导致前爪表征的主要成分生长到后掌表征的相邻边界，因此与使用一个主要成分相比，拟合两个成分不再导致更好的拟合。塑性后表示的边界与其次要成分在没有塑性时的边界相同。这些次要成分可能代表从真实神经元表达延伸出来的血管效应，也可能代表相邻区域之间的神经元通讯。无论哪种方式，这些结果都将有助于研究导致神经元表示边界改变的可塑性机制。
Electrical stimulation of the rat forepaw and hindpaw was employed to study the spatial distribution of BOLD fMRI. Averaging of multiple fMRI sessions significantly improved the spatial stability of the BOLD signal and enabled quantitative determination of the boundaries of the BOLD fMRI maps. The averaged BOLD fMRI signal was distributed unevenly over the extent of the map and the data at the boundaries could be modeled with major and minor spatial components. Comparison of three-dimensional echo-planar imaging (EPI) fMRI at isotropic 300 μm resolution demonstrated that the border locations of the major spatial component of BOLD signal did not overlap between the forepaw and hindpaw maps. Interestingly, the border positions of the minor BOLD fMRI spatial components extended significantly into neighboring representations. Similar results were found for cerebral blood volume (CBV) weighted fMRI obtained using iron oxide particles, suggesting that the minor spatial components may not be due to vascular mislocalization typically associated with BOLD fMRI. Comparison of the BOLD fMRI maps of the forepaw and hindpaw to histological determination of these representations using cytochrome oxidase (CO) staining demonstrated that the major spatial component of the BOLD fMRI activation maps accurately localizes the borders. Finally, 2–3 weeks following peripheral nerve denervation, cortical reorganization/plasticity at the boundaries of somatosensory limb representations in adult rat brain was studied. Denervation of the hindpaw caused a growth in the major component of forepaw representation into the adjacent border of hindpaw representation, such that fitting to two components no longer led to a better fit as compared to using one major component. The border of the representation after plasticity was the same as the border of its minor component in the absence of any plasticity. It is possible that the minor components represent either vascular effects that extend from the real neuronal representations or the neuronal communication between neighboring regions. Either way the results will be useful for studying mechanisms of plasticity that cause alterations in the boundaries of neuronal representations.
登录
查看更多内容
定位人类主要视觉皮层的功能和解剖边界。
影响因子：
5.7
作者：
Hinds O;Polimeni JR;Rajendran N;Balasubramanian M;Amunts K;Zilles K;Schwartz EL;Fischl B;Triantafyllou C
通讯作者：
Triantafyllou C
影响因子：
3
作者：
Bock, Nicholas A.;Kocharyan, Ara;Liu, Junjie V.;Silva, Afonso C.
通讯作者：
Silva, Afonso C.
影响因子：
5.7
作者：
Jin, Tao;Kim, Seong-Gi
通讯作者：
Kim, Seong-Gi
影响因子：
3.3
作者：
GRUETTER, R
通讯作者：
GRUETTER, R
影响因子：
2.5
作者：
CHAPIN, JK;SADEQ, M;GUISE, JLU
通讯作者：
GUISE, JLU