First full-brain map of insects completed

An international team led by Johns Hopkins University in the United States and the University of Cambridge in the United Kingdom has completed the most advanced insect brain map to date, depicting every neural connection in the brain of a fruit fly larva for the first time. This is a milestone achievement in the field of neuroscience, bringing scientists closer to a true understanding of the mechanism of thinking, supporting future brain research and inspiring new machine learning architectures. The research results were published in the journal Science on the 9th.

A complete set of neurons in an insect brain, reconstructed using synaptic-resolution electron microscopy. Image credit: Johns Hopkins University/University of Cambridge

Since the 1970s, when the brain mapping process began with roundworms, which eventually produced a partial map and won a Nobel Prize, parts of the connectome have been mapped in many systems, including fruit flies, mice, and even humans. But these reconstructions usually represent only a small part of the entire brain, and comprehensive connectomes have only been generated for a few small species with a few hundred to a few thousand neurons, such as roundworms, larval sea squirts, and larval marine annelid worms.

The connectome of the Drosophila melanogaster larva generated by the research team is the most complete and extensive insect brain map completed to date. It includes 3,016 neurons and 548,000 connections between them.

A diagram depicting connectivity, with neurons represented as dots and neurons with more similar connectivity drawn closer together. Lines depict connections between neurons. The border of the diagram shows example neuron morphology. Image credit: Johns Hopkins University/University of Cambridge

The research team deliberately chose fruit fly larvae because, for insects, this species shares many basic biological characteristics with humans, and it also has rich learning and decision-making behaviors, making it one of the most useful model organisms in neuroscience. For practical purposes, researchers can also image its relatively compact brain and reconstruct its circuits within a reasonable time frame.

Source: Science and Technology Daily