The forebrain plays a critical role in a broad range of neural processes encompassing sensory integration and initiation/selection of behaviour. The forebrain functions through an interaction between different cortical areas, the thalamus, the basal ganglia with the dopamine system, and the habenulae. The ambition here is to compare the mammalian forebrain with that of the lamprey representing the oldest now living group of vertebrates, by a review of earlier studies. We show that the lamprey dorsal pallium has a motor, a somatosensory, and a visual area with retinotopic representation. The lamprey pallium was previously thought to be largely olfactory. There is also a detailed similarity between the lamprey and mammals with regard to other forebrain structures like the basal ganglia in which the general organisation, connectivity, transmitters and their receptors, neuropeptides, and expression of ion channels are virtually identical. These initially unexpected results allow for the possibility that many aspects of the basic design of the vertebrate forebrain had evolved before the lamprey diverged from the evolutionary line leading to mammals. Based on a detailed comparison between the mammalian forebrain and that of the lamprey and with due consideration of data from other vertebrate groups, we propose a compelling account of a pan-vertebrate schema for basic forebrain structures, suggesting a common ancestry of over half a billion years of vertebrate evolution.
Brain Behav Evol

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七鳃鳗前脑——进化意义

前脑在包括感觉整合和行为的启动/选择在内的广泛的神经过程中起着至关重要的作用。前脑通过不同皮质区域、丘脑、具有多巴胺系统的基底神经节和缰核之间的相互作用发挥作用。这里的目标是通过对早期研究的回顾，将哺乳动物的前脑与代表现在最古老的脊椎动物群的七鳃鳗的前脑进行比较。我们表明七鳃鳗背侧大脑皮层具有运动、体感和具有视网膜主题表示的视觉区域。以前认为七鳃鳗主要是嗅觉的。七鳃鳗和哺乳动物之间在其他前脑结构（如基底神经节）方面也有详细的相似之处，其中一般组织、连接性、递质及其受体、神经肽和离子通道的表达几乎相同。这些最初出乎意料的结果表明，脊椎动物前脑基本设计的许多方面可能在七鳃鳗从导致哺乳动物的进化线分化之前就已经进化了。基于哺乳动物前脑与七鳃鳗前脑之间的详细比较，并适当考虑其他脊椎动物群的数据，我们提出了一个令人信服的关于基本前脑结构的泛脊椎动物模式的描述，表明超过 50 亿的共同祖先多年的脊椎动物进化。这些最初出乎意料的结果表明，脊椎动物前脑基本设计的许多方面可能在七鳃鳗从导致哺乳动物的进化线分化之前就已经进化了。基于哺乳动物前脑与七鳃鳗前脑之间的详细比较，并适当考虑其他脊椎动物群的数据，我们提出了一个令人信服的关于基本前脑结构的泛脊椎动物模式的描述，表明超过 50 亿的共同祖先多年的脊椎动物进化。这些最初出乎意料的结果表明，脊椎动物前脑基本设计的许多方面可能在七鳃鳗从导致哺乳动物的进化线分化之前就已经进化了。基于哺乳动物前脑与七鳃鳗前脑之间的详细比较，并适当考虑其他脊椎动物群的数据，我们提出了一个令人信服的关于基本前脑结构的泛脊椎动物模式的描述，表明超过 50 亿的共同祖先多年的脊椎动物进化。
大脑行为进化