Salas Cosme, Broglio Cristina, Durán Emilio, Gómez Antonia, Ocaña Francisco M, Jiménez-Moya Fernando, Rodríguez Fernando
Laboratory of Psychobiology, University of Sevilla, Sevilla, Spain.
Zebrafish. 2006;3(2):157-71. doi: 10.1089/zeb.2006.3.157.
Traditionally, brain and behavior evolution was viewed as an anagenetic process that occurred in successive stages of increasing complexity and advancement. Fishes, considered the most primitive vertebrates, were supposed to have a scarcely differentiated telencephalon, and limited learning capabilities. However, recent developmental, neuroanatomical, and functional data indicate that the evolution of brain and behavior may have been more conservative than previously thought. Experimental data suggest that the properties and neural basis of learning and memory are notably similar among teleost fish and land vertebrates. For example, lesion studies show that the teleost cerebellum is essential in classical conditioning of discrete motor responses. The lateral telencephalic pallium of the teleost fish, proposed as homologous to the hippocampus, is selectively involved in spatial learning and memory, and in trace classical conditioning. In contrast, the medial pallium, considered homologous to the amygdala, is involved in emotional conditioning in teleost fish. The data reviewed here show a remarkable parallelism between mammals and teleost fish concerning the role of different brain centers in learning and memory and cognitive processes. These evidences suggest that these separate memory systems could have appeared early during the evolution of vertebrates, having been conserved through phylogenesis.
传统上，大脑和行为的进化被视为一个渐变性过程，它发生在复杂性和先进性不断增加的连续阶段。鱼类被认为是最原始的脊椎动物，其端脑几乎没有分化，学习能力有限。然而，最近的发育、神经解剖学和功能数据表明，大脑和行为的进化可能比以前认为的更为保守。实验数据表明，硬骨鱼和陆地脊椎动物在学习和记忆的特性及神经基础方面显著相似。例如，损伤研究表明，硬骨鱼的小脑在离散运动反应的经典条件反射中至关重要。硬骨鱼的外侧端脑皮质被认为与海马体同源，它选择性地参与空间学习和记忆以及痕迹经典条件反射。相反，被认为与杏仁核同源的内侧皮质则参与硬骨鱼的情绪条件反射。这里回顾的数据表明，在不同脑区在学习、记忆和认知过程中的作用方面，哺乳动物和硬骨鱼之间存在显著的平行关系。这些证据表明，这些独立的记忆系统可能在脊椎动物进化早期就已出现，并在系统发育过程中得以保留。
