胼胝体压部神经通路在文字、物体与面孔加工中的作用

目的:揭示胼胝体压部神经通路在文字、物体与面孔加工中的作用。方法:利用一系列认知神经心理学方法,对1例(KY)胼胝体压部合并左腹内侧枕颞区梗死患者进行自然视野和左右分视野速视呈现及注视中央点速视呈现汉字、拼音的朗读检测;对自然视野呈现的物体和名人面孔和对注视中央点速视的Chimeric物体图片进行命名;对Chimeric面孔(半男半女)进行性别判断;并利用弥散张量纤维束示踪技术(DTT)确定胼胝体压部纤维束受损情况。同时与1例(CYH)仅左腹内侧枕颞区梗死但不合并胼胝体压部损伤、接受类似检查的患者对照。结果:KY对于自然视野、注视中央点速视呈现的汉字、拼音均出现左半错读;对左右分视野速视的汉字、拼音出现左视野失读;对于自然视野呈现的物体和名人面孔出现部分失认;对于注视中央点速视的Chimeric物体和面孔图片以左半为主进行命名和判断,并且未辨认出为Chimeric图片。DTT显示通过胼胝体压部的枕大钳纤维束通路几乎完全中断。CYH的汉字朗读、物体及面孔识别均正常,能够分辨出Chimeric图片。结论:胼胝体压部神经通路在左/右枕(右/左视野)的文字、物体与面孔视觉信息的传递及视觉整合的过程中起到必要的作用。

The Role of Splenium of Corpus Callosum in Words, Objects and Faces Processing

Objective：To investigate the role of splenium of corpus callosum in words,objects and faces processing.Methods： Based on cognitive neuropsychological study paradigm,we took a series of behavioral tests on KY,a patient suffering from infarctions in the splenium and the left ventral mesial occipitotemporal area.These tests included reading Chinese characters,Pinyin,which were presented in free vision or presented tachistoscopically in central or left/right visual field;naming pictures of objects and famous faces in free vision;naming Chimeric pictures of objects and judging the gender of Chimeric faces（consisting of half male and half female face）.Diffusion tensor tractography（DTT） was taken to confirm the lesion of splenium of corpus callosum one case of.CYH,who accepted similar tests as KY and had lesions only in the left ventral mesial occipitotemporal area,was recruited as control.Results： KY showed left hemiparalexia for Chinese characters and Pinyin presented in free vision and central visual field;and showed left hemialexia for Chinese characters and Pinyin presented in divided visual field.In free vision condition,KY showed agnosia for objects and prosopagnosia for famous faces to some extent.He named Chimeric objects and made gender decisions of Chimeric faces mostly based on the left half object/face and was unaware that these stimuli were chimeric.DTT revealed the total major forceps fibers running through the splenium were disconnected due to the infarction in the splenium.CYH demonstrated normal reading.Although he showed some kind of naming deficits in objects and faces,he recognized them normally.He was of ability to identify the Chimeric pictures.Conclusion： The splenium of corpus callosum plays a necessary role in transferring and integrating visual information of Chinese characters,objects and faces in left and right occipital cortices.