INSERM, U864, Espace et Action, 16 avenue Lépine, Bron 69676, France.
Philos Trans R Soc Lond B Biol Sci. 2011 Feb 27;366(1564):572-85. doi: 10.1098/rstb.2010.0258.
We review evidence showing a right-hemispheric dominance for visuo-spatial processing and representation in humans. Accordingly, visual disorganization symptoms (intuitively related to remapping impairments) are observed in both neglect and constructional apraxia. More specifically, we review findings from the intervening saccade paradigm in humans--and present additional original data--which suggest a specific role of the asymmetrical network at the temporo-parietal junction (TPJ) in the right hemisphere in visual remapping: following damage to the right dorsal posterior parietal cortex (PPC) as well as part of the corpus callosum connecting the PPC to the frontal lobes, patient OK in a double-step saccadic task exhibited an impairment when the second saccade had to be directed rightward. This singular and lateralized deficit cannot result solely from the patient's cortical lesion and, therefore, we propose that it is due to his callosal lesion that may specifically interrupt the interhemispheric transfer of information necessary to execute accurate rightward saccades towards a remapped target location. This suggests a specialized right-hemispheric network for visuo-spatial remapping that subsequently transfers target location information to downstream planning regions, which are symmetrically organized.
我们回顾了证明人类右半球在视空间处理和表现方面具有优势的证据。因此,在忽视和构音障碍性失用症中都观察到视觉组织障碍症状(直观上与重新映射损伤有关)。更具体地说,我们回顾了人类中间歇性扫视范式的研究结果——并提供了额外的原始数据——这表明右半球颞顶交界处(TPJ)的非对称网络在视觉重新映射中具有特定作用:在损伤右侧背侧顶叶皮层(PPC)以及连接 PPC 与额叶的部分胼胝体后,患者 OK 在双步扫视任务中,当第二次扫视必须向右时,表现出损伤。这种单一的、偏侧化的缺陷不可能仅仅是由于患者的皮质损伤所致,因此,我们认为这是由于他的胼胝体损伤,可能会特异性地中断执行准确向右扫视到重新映射目标位置所需的信息的半球间转移。这表明右半球具有专门的视空间重新映射网络,随后将目标位置信息传递到下游的规划区域,这些区域是对称组织的。