Acta Biologica Hungarica

, Volume 55, Issue 1–4, pp 13–19 | Cite as

Properties of Descending Dorsal Unpaired Median (DUM) Neurons of the Locust Suboesophageal Ganglion

  • P. BräunigEmail author
  • M. Burrows
  • O. T. Morris


A group of six dorsal unpaired median (DUM) neurons of the suboesophageal ganglion (SOG) of locusts was studied with neuroanatomical and electrophysiological techniques. The neurons are located posteriorly in the SOG and have axons that descend into the ganglia of the ventral nerve cord, some as far as the terminal abdominal ganglion. Within thoracic ganglia the neurons have profuse dendritic ramifications in many neuropiles, including ventral sensory neuropiles. Based on their projection patterns three different morphological types of neurons can be distinguished. These neurons receive excitatory inputs through sensory pathways that ascend from the thoracic ganglia and are activated by limb movements. They may be involved in the modulation of synaptic transmission in thoracic ganglia.


Neuromodulation insect DUM neuron octopamine biogenic amine 


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© Akadémiai Kiadó, Budapest 2004

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  1. 1.Institut Biologie IIRWTH AachenAachenGermany
  2. 2.Department of ZoologyUniversity of CambridgeCambridgeUK

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