Evolution of the thalamus: a morphological and functional review
Evolution of the thalamus: a morphological and functional review
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DOI：
10.1017/s1472928808000356
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发表时间：
2008-03-01
期刊：
影响因子：
--
通讯作者：
Butler, Ann B.
中科院分区：
文献类型：
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作者：
Butler, Ann B.
前脑的扩大，包括丘脑的细化，在不同的脊椎动物群体中独立发生。在大多数脊椎动物中可以识别出丘脑背侧和腹侧区域，但GABA能神经元成分的存在存在差异。丘脑向背侧丘脑的抑制性网状核样输入可能是一个共同的特征，丘脑背侧核的两个部分，丘脑丘脑和胶丘脑的组织计划也可能是共同的特征。哺乳动物和蜥蜴(爬行动物和鸟类)对这些分类的不同、独立的阐述，使得它们的进化关系难以辨别。并不是所有哺乳动物丘脑皮质回路的关键特征都存在于其他脊椎动物中，但鸟类具有迄今为止已发现的大多数特征。这些包括特定的和非特定的丘脑中继神经元，相互的丘脑顶叶投射，以及具有某些但不是全部行为学特征的GABA能丘脑网状核。因为鸟类与哺乳动物共享许多更高水平的认知能力，因此，可能也有更高水平的意识，所以对丘脑皮质(丘脑)回路的比较可能会被证明是检验功能假说的一个富有成效的资源。与精选的其他脊椎动物进行比较也可能被证明是有价值的，这些脊椎动物的大脑与身体的比例同样较大，并且也表现出一些认知上的复杂行为，如旗鱼。
Enlargement of the forebrain, including elaboration of the thalamus, has occurred independently within different groups of vertebrates. Dorsal and ventral thalamic territories can be identified in most vertebrates, with variations in the presence of GABAergic neuronal components. An inhibitory thalamic reticular nucleus-like input to the dorsal thalamus might be a common feature, as might the organizational plan of two divisions of the dorsal thalamus, the lemnothalamus and collothalamus. Differential, independent elaboration of these divisions occurred in mammals and sauropsids (reptiles and birds), making their evolutionary relationships challenging to discern. Not all of the crucial features identfied for mammalian thalamocortical circuitry are present in other vertebrates, but birds share the most features identified to date. These include specific and nonspecific thalamic relay neurons, reciprocal pallial projections, and a GABAergic thalamic reticular nucleus with some but not all hodological features. Because birds share many higher-level cognitive abilities and, thus, possibly higher-level consciousness, with mammals, comparison of the thalamocortical (thalamopallial) circuitry might prove a fruitful resource for testing functional hypotheses. Comparisons with selected other vertebrates that likewise have relatively large brain:body ratios and also exhibit some cognitively sophisticated behaviors, such as cichlidfish, might also prove valuable.