Butler A B
Ivory Tower Neurobiology Institute, Arlington, VA 22207, USA.
Brain Behav Evol. 1995;46(4-5):209-23. doi: 10.1159/000113275.
In anamniotes, the dorsal thalamus comprises: (1) a caudal division, the collothalamus, which receives its predominant input from the midbrain roof and projects ipsilaterally to the telencephalon, predominantly to the striatum, and (2) a rostral division, the lemnothalamus, which predominantly receives a direct retinal (lemniscal) input and projects bilaterally to the telencephalon, predominantly to the pallium. In amniotes, collothalamic nuclei relay visual, auditory, and somatosensory-multisensory inputs from the midbrain roof to the ipsilateral telencephalon, terminating in both striatum and pallium. For example, the collothalamic visual nuclei consist of the LP-pulvinar complex in mammals and nucleus rotundus in diapsid reptiles, birds, and turtles. Among amniotes, the latter nuclei are homologous to each other as discrete nuclei, as are the collothalamic auditory and collothalamic somatosensory-multisensory nuclei. Lemnothalamic nuclei (and nuclear groups) in amniotes predominantly (and/or plesiomorphically) receive lemniscal inputs; some project to the telencephalon bilaterally, and most, in contrast to collothalamic nuclei, do not project to the striatum. In mammals, the lemnothalamic nuclei include most of those in the anterior, medial, intralaminar, and ventral nuclear groups and the dorsal lateral geniculate nucleus. In diapsid reptiles, they include the dorsomedial and dorsolateral anterior nuclei and the dorsal lateral optic nucleus; comparable nuclei are present in birds and turtles, with birds additionally having a discrete somatosensory lemniscal relay nucleus. These lemnothalamic nuclei in each amniote radiation are homologous as a field to the lemnothalamus (i.e., nucleus anterior) in anamniotes. Both divisions of the dorsal thalamus were elaborated to some degree in the common ancestral amniote stock. A further major elaboration of the lemnothalamus characterized the ancestral stock of mammals and may have been one of the key events in early mammalian evolution. Birds have independently, to a lesser degree, elaborated the lemnothalamus.
在无羊膜动物中，背侧丘脑包括：（1）一个尾侧部分，即丘脑枕，它主要从中脑顶盖接收输入，并同侧投射到端脑，主要是纹状体；（2）一个头侧部分，即丘系丘脑，它主要接收直接的视网膜（丘系）输入，并双侧投射到端脑，主要是大脑皮质。在羊膜动物中，丘脑枕核将来自中脑顶盖的视觉、听觉和躯体感觉 - 多感觉输入中继到同侧端脑，终止于纹状体和大脑皮质。例如，丘脑枕视觉核在哺乳动物中由外侧后核 - 丘脑枕复合体组成，在双孔类爬行动物、鸟类和龟类中由圆核组成。在羊膜动物中，后一组核作为离散的核彼此同源，丘脑枕听觉核和丘脑枕躯体感觉 - 多感觉核也是如此。羊膜动物中的丘系丘脑核主要（和/或原始地）接收丘系输入；一些双侧投射到端脑，与丘脑枕核相比，大多数不投射到纹状体。在哺乳动物中，丘系丘脑核包括前核群、内侧核群、板内核群和腹侧核群中的大多数以及背外侧膝状体核。在双孔类爬行动物中，它们包括背内侧和背外侧前核以及背外侧视核；鸟类和龟类中存在类似的核，鸟类还另外有一个离散的躯体感觉丘系中继核。每个羊膜动物类群中的这些丘系丘脑核作为一个区域与无羊膜动物中的丘系丘脑（即前核）同源。背侧丘脑的两个部分在共同的羊膜动物祖先种群中都有一定程度的演化。丘系丘脑的进一步重大演化是哺乳动物祖先种群的特征，可能是早期哺乳动物进化中的关键事件之一。鸟类在较小程度上独立地演化了丘系丘脑。
