Department of Physiology, Monash University, Clayton, VIC, Australia.
Neuroscience Program, Biomedicine Research Institute, Monash University, Clayton, VIC, Australia.
Cereb Cortex. 2019 Apr 1;29(4):1473-1495. doi: 10.1093/cercor/bhy044.
Area 10, located in the frontal pole, is a unique specialization of the primate cortex. We studied the cortical connections of area 10 in the New World Cebus monkey, using injections of retrograde tracers in different parts of this area. We found that injections throughout area 10 labeled neurons in a consistent set of areas in the dorsolateral, ventrolateral, orbital, and medial parts of the frontal cortex, superior temporal association cortex, and posterior cingulate/retrosplenial region. However, sites on the midline surface of area 10 received more substantial projections from the temporal lobe, including clear auditory connections, whereas those in more lateral parts received >90% of their afferents from other frontal areas. This difference in anatomical connectivity reflects functional connectivity findings in the human brain. The pattern of connections in Cebus is very similar to that observed in the Old World macaque monkey, despite >40 million years of evolutionary separation, but lacks some of the connections reported in the more closely related but smaller marmoset monkey. These findings suggest that the clearer segregation observed in the human frontal pole reflects regional differences already present in early simian primates, and that overall brain mass influences the pattern of cortico-cortical connectivity.
10 区位于额极，是灵长类皮质的一个独特特化区。我们使用逆行示踪剂在该区域的不同部位注射，研究了新世界卷尾猴 10 区的皮质连接。我们发现，10 区的注射部位标记了额皮质背外侧、腹外侧、眶部和内侧部分、上颞联合皮质和后扣带/后顶叶区域的一组一致的神经元。然而，10 区中线表面的部位从中颞叶接收更大量的投射，包括明确的听觉连接，而那些更外侧的部位则接收 90%以上的传入纤维来自其他额区。这种解剖连接的差异反映了人类大脑的功能连接发现。尽管在 4000 多万年的进化分离后，卷尾猴的连接模式与旧世界猕猴非常相似，但它缺乏在更密切相关但更小的狨猴中报告的一些连接。这些发现表明，人类额极观察到的更明显的分离反映了早期灵长类动物中已经存在的区域差异，而大脑总体质量影响皮质-皮质连接模式。
