名人面孔、动物和人造物类别特异性命名区脑定位的功能磁共振研究(英文)

目的在一些疾病中,病人会出现类别特异性的识别和命名障碍,但有关名人面孔、动物和人造物三种不同类型命名任务的脑定位研究仍存在争议。本研究旨在利用功能磁共振(fMRI)研究这三种不同类型命名任务的脑激活特点。方法采用SPM8软件进行脑功能图像分析,命名任务与基线任务采用t检验统计,然后进行群组分析,结果用MNI坐标表示,解剖位置用XJview8自动标记。结果名人面孔命名区主要位于双侧前颞叶包括海马和杏仁核,且存在左侧优势,同时还激活双侧颞下回三角部和盖部;命名动物主要激活左侧辅助运动区;而命名人造物主要激活左侧运动前区和右侧辅助运动区,三种任务均有双侧梭状回激活,但命名人造物激活区范围比其余两种任务都大。结论人、动物和人造物三种不同类型命名任务的脑定位存在差异,这提示在术中定位功能区过程中,需要选择不同类型的命名任务,以减少阴性刺激和术后永久性功能障碍的发生率。

Functional MRI mapping of category-specific sites associated with naming of famous faces, animals and man-made objects

Objective

Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain controversial. The present study aimed to study the specific areas involved in naming pictures of these 3 categories using functional magnetic resonance imaging.

Methods

Functional images were analyzed using statistical parametric mapping and the 3 different contrasts were evaluated using t statistics by comparing the naming tasks to their baselines. The contrast images were entered into a random-effects group level analysis. The results were reported in Montreal Neurological Institute coordinates, and anatomical regions were identified using an automated anatomical labeling method with XJview 8.

Results

Naming famous faces caused more activation in the bilateral head of the hippocampus and amygdala with significant left dominance. Bilateral activation of pars triangularis and pars opercularis in the naming of famous faces was also revealed. Naming animals evoked greater responses in the left supplementary motor area, while naming man-made objects evoked more in the left premotor area, left pars orbitalis and right supplementary motor area. The extent of bilateral fusiform gyri activation by naming man-made objects was much larger than that by naming of famous faces or animals. Even in the overlapping sites of activation, some differences among the categories were found for activation in the fusiform gyri.

Conclusion

The cortices involved in the naming process vary with the naming of famous faces, animals and man-made objects. This finding suggests that different categories of pictures should be used during intra-operative language mapping to generate a broader map of language function, in order to minimize the incidence of false-negative stimulation and permanent post-operative deficits.