Iannetti G D, Porro C A, Pantano P, Romanelli P L, Galeotti F, Cruccu G
Dipartimento Scienze Neurologiche, Università La Sapienza, Roma, Italy.
Neuroimage. 2003 Jul;19(3):906-12. doi: 10.1016/s1053-8119(03)00139-3.
Clinical, neurophysiological, and neuroimaging studies have yielded controversial results about the representation of the face in the somatosensory cortex. To clarify this issue we mechanically stimulated the left forehead (ophthalmic trigeminal division, V1) and left lower lip (mandibular trigeminal division, V3) in 14 healthy volunteers during acquisition of whole-brain fMRI images. During V1 and V3 stimulation the fMRI signal in the primary (SI) and secondary (SII) somatosensory cortices in the contralateral hemisphere increased. Within both SI and SII, the foci activated by stimulation of the two trigeminal divisions largely overlapped. In contrast, the ipsilateral representation differed. Whereas V3 stimulation activated the contralateral somatosensory cortex alone, V1 stimulation activated SI and SII bilaterally. These results to some extent contrast with electrophysiological data in monkeys and disclose distinct cortical representations within facial territories in humans.
临床、神经生理学和神经影像学研究在体感皮层中面部表征方面得出了有争议的结果。为了阐明这个问题，我们在14名健康志愿者获取全脑功能磁共振成像（fMRI）图像期间，对其左前额（眼支三叉神经，V1）和左下唇（下颌支三叉神经，V3）进行了机械刺激。在V1和V3刺激期间，对侧半球的初级（SI）和次级（SII）体感皮层中的fMRI信号增加。在SI和SII内，由两个三叉神经分支刺激激活的焦点在很大程度上重叠。相比之下，同侧表征有所不同。V3刺激仅激活对侧体感皮层，而V1刺激双侧激活SI和SII。这些结果在一定程度上与猴子的电生理数据形成对比，并揭示了人类面部区域内不同的皮层表征。
