The nervous systems of Echinodermata: Recent results and new approaches

Abstract

The echinoderm nervous system is the least studied of all the major phyla. It does however have many unusual or unique features. There are two distinct and separate nervous systems, one of which may be mesodermal in origin. The nervous system is non-centralised and whole body coordination in complex behaviours appears to be able to be controlled by quite different parts of the nervous system depending upon circumstances. The action potential appears to be based on Ca + + ions and not Na +, and connective tissue is mutable and innervated. Recently there has been an increase in activity looking at neuropeptides and other modulators. This review looks at what has been achieved and offers suggestions for future research.