Kopietz Rainer, Sakar Vehbi, Albrecht Jessica, Kleemann Anna Maria, Schöpf Veronika, Yousry Indra, Linn Jennifer, Fesl Gunther, Wiesmann Martin
Department of Neuroradiology, University of Munich, Marchioninistrasse 15, Munich, Germany
Klin Neuroradiol. 2009 Jun;19(2):135-44. doi: 10.1007/s00062-009-8022-3. Epub 2009 May 23.
Since the work of Penfield & Rasmussen it is well established that the human primary somatosensory cortex is organized somatotopically. However, the order of the representation of the face is still a matter of discussion, i.e., it is yet unclear whether the face is represented upside-down or vice versa in the somatosensory cortex.
In a functional magnetic resonance imaging study (n = 30), tactile stimuli to three different locations on each side of the face were applied using a pneumatic device. Locations of stimulation corresponded to the three branches of the trigeminal nerve (forehead, cheek, chin). To determine the representation of the face on primary and secondary somatosensory cortices, peak coordinates within these regions were analyzed subjectwise.
Contralateral activation of the primary somatosensory cortex following tactile stimulation of the face was found, whereas the secondary somatosensory cortices were activated bilaterally. However, differences between activation coordinates of different tactile stimuli applied to one side of the face were not statistically significant.
Tactile stimulation of the face leads to contralateral activation of primary and bilateral activation of secondary somatosensory cortices. Using the authors' methodological approach it was not possible to detect a somatotopic organization related to different facial areas.
自彭菲尔德和拉斯穆森的研究以来，人们已经充分认识到人类初级体感皮层是按躯体定位组织的。然而，面部表征的顺序仍然是一个有争议的问题，即在体感皮层中，面部是倒置表征还是正立表征尚不清楚。
在一项功能磁共振成像研究（n = 30）中，使用气动装置对脸部两侧的三个不同位置施加触觉刺激。刺激位置对应于三叉神经的三个分支（额头、脸颊、下巴）。为了确定面部在初级和次级体感皮层上的表征，对这些区域内的峰值坐标进行个体分析。
发现对面部进行触觉刺激后，初级体感皮层出现对侧激活，而次级体感皮层双侧激活。然而，应用于面部一侧的不同触觉刺激的激活坐标之间的差异无统计学意义。
对面部的触觉刺激导致初级体感皮层的对侧激活和次级体感皮层的双侧激活。采用作者的方法无法检测到与不同面部区域相关的躯体定位组织。
