Morphology and Physiology of the Ascidian Nervous Systems and the Effectors

Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1029)


Neurobiology in ascidians has made many advances. Ascidians have offered natural advantages to researchers, including fecundity, structural simplicity, invariant morphology, and fast and stereotyped developmental processes. The researchers have also accumulated on this animal a great deal of knowledge, genomic resources, and modern genetic techniques. A recent connectomic analysis has shown an ultimately resolved image of the larval nervous system, whereas recent applications of live imaging and optogenetics have clarified the functional organization of the juvenile nervous system. Progress in resources and techniques have provided convincing ways to deepen what we have wanted to know about the nervous systems of ascidians. Here, the research history and the current views regarding ascidian nervous systems are summarized.


Simple brain Motor ganglion Muscle Motor control Development of membrane excitability Chordate evolution Motor pattern generation Metamorphosis Connectome 



I am grateful for helpful comments by the editor, Dr. Yasunori Sasakura, which greatly improved the manuscript.


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Department of Biology, Faculty of Agriculture and Life ScienceHirosaki UniversityHirosakiJapan

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