Wikipedia, Andre KarwathIn a fruit fly’s antennae, two neighboring neurons can stop each other from firing even if they do not share any direct connections, and help the insect to process smells, according to a study published today (21 November) in Nature. This means of communication, called ephaptic coupling, results when the electric field produced by one neuron silences its neighbor, instead of sending neurotransmitters across a synapse.
“[Ephaptic coupling has] been in the literature for a long time, but there are very few cases where these interactions have affected behavior in an actual organism,” said John Carlson, a Yale University biologist who led the study. “This is terra incognita.”
Jean-Pierre Rospars from INRA in France predicted the existence of these ephatic interactions in the sense organs of flies in 2004. “But nothing can replace a direct experimental proof as provided now by [this new study],” he said, describing the experiments as “difficult, ingenious, and complete.”
In the antennae of Drosophila melanogaster, olfactory neurons are bundled into fluid-filled hairs called sensilla. Each sensillum contains two to four neurons, which are all tuned to different smells and grouped in specific ways. “A strawberry neuron ...