Do jellyfish have central nervous systems?

@article{Satterlie2011DoJH,
  title={Do jellyfish have central nervous systems?},
  author={Richard A. Satterlie},
  journal={Journal of Experimental Biology},
  year={2011},
  volume={214},
  pages={1215 - 1223}
}
  • R. Satterlie
  • Published 15 April 2011
  • Biology
  • Journal of Experimental Biology
Summary The traditional view of the cnidarian nervous system is of a diffuse nerve net that functions as both a conducting and an integrating system; this is considered an indicator of a primitive condition. Yet, in medusoid members, varying degrees of nerve net compression and neuronal condensation into ganglion-like structures represent more centralized integrating centers. In some jellyfish, this relegates nerve nets to motor distribution systems. The neuronal condensation follows a precept… 

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References

SHOWING 1-10 OF 57 REFERENCES

Central Neural Circuitry in the Jellyfish Aglantha

Twelve neuronal and two excitable epithelial conduction systems are described and their interactions summarized in Aglantha, which lacks a brain, but the two marginal nerve rings function together as a central nervous system.

The bilaterally symmetric rhopalial nervous system of box jellyfish

The strikingly complex and partially bilaterally symmetrical nervous system found in each rhopalium of the box jellyfish, Tripedalia cystophora, is described and an atlas-like series of drawings are presented, indicating that visual processing and integration at least partly happen within the rhopalia.

The ring nerve of the box jellyfish Tripedalia cystophora

The morphology of the ring nerve of the box jellyfish Tripedalia cystophora is described as ascertained by normal histological techniques, immunohistochemistry and transmission electron microscopy, and the number of cells in theRing nerve is estimated by counting their nuclei.

Bilaterally symmetrical rhopalial nervous system of the box jellyfish Tripedalia cystophora

The strikingly complex and partially bilaterally symmetrical nervous system found in each rhopalium of the box jellyfish, Tripedalia cystophora, is described and an atlas‐like series of drawings are presented, indicating that visual processing and integration at least partly happen within the rhopalia.

Rhopalia are integrated parts of the central nervous system in box jellyfish

Results indicate that cubomedusae have one coherent CNS including the rhopalia, and a novel gastrodermal nerve has been found in the stalk; this nerve is not involved in visual processing but is likely to be mechanosensory and part of a proprioceptory system.

Neurobiology of Polyorchis. II. Structure of effector systems.

The gross and fine morphology of the major effector systems in the anthomedusan, Polyorchis penicillatus, is described and discussed in relation to the known physiological and behavioral properties

The anatomy of the nervous system of the hydrozoan jellyfish, Polyorchis penicillatus, as revealed by a monoclonal antibody

Immunohistochemical labelling with mAb 5C6 of whole-mount preparations and paraffin sections provided a far more complete picture of the organisation of the hydromedusan nervous system than was previously available when using neuronal labelling techniques that restrict labelling to certain neuronal types.

Croonian Lecture - The elementary nervous system

  • C. Pantin
  • Biology
    Proceedings of the Royal Society of London. Series B - Biological Sciences
  • 1952
Both physiological and critical histological studies show that the coelenterate nerve-net is synaptic, and there is evidence that several distinct kinds of spontaneous activity are built into the normal behaviour mechanisms.

Neuronal control of locomotion in hydrozoan medusae

The swimming control systems of 13 hydromedusan species were examined electrophysiologically and morphologically to suggest that the basic organization of swimming system components is similar and may perform a pacemaker function.

Ultrastructure of synapses in the first-evolved nervous systems

The lack of postjunctional folds at neuromuscular synapses and the presence of fewer and somewhat larger synaptic vesicles in the more primitive animals suggests that neuropeptides evolved as neurotransmitters early in the animal kingdom.
...