Bourne James A, Rosa Marcello G P
Department of Physiology and Centre for Brain and Behaviour, Monash University, Melbourne, VIC 3800, Australia.
Cereb Cortex. 2006 Mar;16(3):405-14. doi: 10.1093/cercor/bhi119. Epub 2005 Jun 8.
It has been suggested that the development of the cerebral cortex reflects its hierarchical organization, with the primary sensory areas being the first to reach structural and functional maturity, and higher-order association areas being the last. In the present study, we labelled the cortex of New World marmoset monkeys of late fetal and early postnatal ages with an antibody to non-phosphorylated neurofilament, a marker of structural maturation of a subset of pyramidal cells. Supporting the concept of hierarchical maturation, we found that at birth labelled cells were found in the primary visual, auditory and somatosensory areas, but not in most other cortical fields. The exception was visual area MT, which revealed an infragranular pattern of labelling comparable to the one observed in the primary areas, as well as some supragranular staining. In MT, an adult-like pattern of labelled cells, including both supragranular and infragranular layer neurons, emerged within the first postnatal month. In comparison, the development of other extrastriate areas was delayed, with the first signs of neurofilament staining not present until the third week. The present results support the concept of MT as another primary visual area, an idea previously advanced on the basis of functional and anatomical evidence.
有人提出，大脑皮层的发育反映了其层级组织，初级感觉区域最先达到结构和功能成熟，高阶联合区域最后成熟。在本研究中，我们用抗非磷酸化神经丝抗体标记了妊娠晚期和出生后早期的新大陆狨猴的皮层，非磷酸化神经丝是锥体细胞亚群结构成熟的标志物。支持层级成熟概念的是，我们发现出生时在初级视觉、听觉和躯体感觉区域发现了标记细胞，但在大多数其他皮层区域未发现。例外的是视觉区域MT，其显示出与初级区域观察到的类似的颗粒下层标记模式，以及一些颗粒上层染色。在MT中，包括颗粒上层和颗粒下层神经元在内的标记细胞的成年样模式在出生后的第一个月内出现。相比之下，其他纹外区域的发育延迟，直到第三周才出现神经丝染色的最初迹象。本研究结果支持将MT视为另一个初级视觉区域的概念，这一观点此前已基于功能和解剖学证据提出。
