Ahlfors Seppo P, Jones Stephanie R, Ahveninen Jyrki, Hämäläinen Matti S, Belliveau John W, Bar Moshe
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA 02129, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02135, USA.
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA 02129, USA; Brown University, Providence, RI, USA.
Neurosci Lett. 2015 Jan 12;585:149-54. doi: 10.1016/j.neulet.2014.11.029. Epub 2014 Nov 20.
Identifying inter-area communication in terms of the hierarchical organization of functional brain areas is of considerable interest in human neuroimaging. Previous studies have suggested that the direction of magneto- and electroencephalography (MEG, EEG) source currents depend on the layer-specific input patterns into a cortical area. We examined the direction in MEG source currents in a visual object recognition experiment in which there were specific expectations of activation in the fusiform region being driven by either feedforward or feedback inputs. The source for the early non-specific visual evoked response, presumably corresponding to feedforward driven activity, pointed outward, i.e., away from the white matter. In contrast, the source for the later, object-recognition related signals, expected to be driven by feedback inputs, pointed inward, toward the white matter. Associating specific features of the MEG/EEG source waveforms to feedforward and feedback inputs could provide unique information about the activation patterns within hierarchically organized cortical areas.
根据功能性脑区的层次组织来识别区域间通信在人类神经影像学中具有相当大的研究价值。先前的研究表明，磁脑电图（MEG、EEG）源电流的方向取决于进入皮层区域的层特异性输入模式。我们在一个视觉物体识别实验中检测了MEG源电流的方向，在该实验中，梭状回区域的激活存在由前馈或反馈输入驱动的特定预期。早期非特异性视觉诱发反应的源，大概对应于前馈驱动的活动，指向外侧，即远离白质。相比之下，后期与物体识别相关信号的源，预期由反馈输入驱动，指向内侧，朝向白质。将MEG/EEG源波形的特定特征与前馈和反馈输入相关联，可以提供有关分层组织的皮层区域内激活模式的独特信息。
