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Updated: Jul 4, 2026
11:27
Selective Tracing of Auditory Fibers in the Avian Embryonic Vestibulocochlear Nerve
Published on: March 18, 2013
Evolutionarily conserved coding properties of auditory neurons across grasshopper species
Daniela Neuhofer1, Sandra Wohlgemuth, Andreas Stumpner
1Department of Biology, Humboldt Universität zu Berlin, Berlin, Germany.
Proceedings. Biological Sciences
|May 29, 2008
Summary
Auditory interneurons in grasshoppers show conserved coding properties across species. This suggests stabilizing selection preserved these neural pathways, preventing adaptation to specific acoustic communication needs.
Area of Science:
- Neuroscience
- Evolutionary Biology
- Bioacoustics
Background:
- Auditory interneurons play a crucial role in processing sound signals.
- The 'efficient coding' hypothesis predicts neural pathways adapt to species-specific communication signals.
- Investigating conserved coding properties can reveal evolutionary constraints on neural systems.
Purpose of the Study:
- To compare the encoding properties of homologous auditory interneurons in two distantly related grasshopper species.
- To determine if auditory pathways adapt to species-specific acoustic signals or are evolutionarily conserved.
Main Methods:
- Electrophysiological recordings of spike trains from auditory interneurons in Locusta migratoria and Chorthippus biguttulus.
- Utilized species-specific stridulation signals of Chorthippus biguttulus as auditory stimuli.
- Employed a spike train metric to quantify similarities and differences in neuronal responses.
Main Results:
- Homologous auditory interneurons in both species exhibited highly similar response patterns to the same auditory stimuli.
- Interspecific differences in neuronal responses were not significantly greater than intraspecific variations.
- The auditory pathway's coding characteristics were found to be strongly conserved between the two species.
Conclusions:
- The thoracic auditory pathway in grasshoppers is evolutionarily conserved, with coding properties largely unchanged despite species divergence.
- Stabilizing selective forces appear to maintain these conserved coding characteristics.
- Contrary to the 'efficient coding' hypothesis, adaptation to specific acoustic communication needs was not observed, suggesting constraints on neural evolution.
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01:13The Cochlea
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01:22Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
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