Revolutionary map of neurons published
Friday March 10th 2023
The first map to show every neuron, wired together in the brain of the fruit fly larva was published last night.
It is hoped this connectome of 3,016 neurons that make up the larva's brain and the detailed circuitry of neural pathway will help researchers understand the basic principles by which signals travel through the brain at the neural level and lead to behaviour and learning.
Led by Professor Marta Zlatic and Professor Albert Cardona of the Medical Research Council Laboratory of Molecular Biology, University of Cambridge, UK, the groundbreaking research is published in the latest edition of Science.
Prof Zlatic said: "The way the brain circuit is structured influences the computations the brain can do. But, up until this point, we've not seen the structure of any brain except of the roundworm C. elegans, the tadpole of a low chordate, and the larva of a marine annelid, all of which have several hundred neurons.
"This means neuroscience has been mostly operating without circuit maps. Without knowing the structure of a brain, we're guessing on the way computations are implemented. But now, we can start gaining a mechanistic understanding of how the brain works."
She said current technology is not yet advanced enough to map the connectome for higher animals, such as large mammals, but added: "All brains are similar - they are all networks of interconnected neurons - and all brains of all species have to perform many complex behaviours: they all need to process sensory information, learn, select actions, navigate their environments, choose food, recognise their conspecifics, escape from predators etc.
"In the same way that genes are conserved across the animal kingdom, I think that the basic circuit motifs that implement these fundamental behaviours will also be conserved."
Profs Zlatic and Cardona and colleagues scanned thousands of slices of the larva's brain using a high-resolution electron microscope before reconstructing the images into a map of the fly's brain and annotating the connections between neurons.
As well as mapping the 3016 neurons, they also mapped 548,000 synapses and developed computational tools to identify likely pathways of information flow and different types of circuit motifs in the insect's brain.
They found some of the structural features are the same as state-of-the-art deep learning architecture.
Jo Latimer, head of neurosciences and mental health at the Medical Research Council, said: "This is an exciting and significant body of work by colleagues at the MRC Laboratory of Molecular Biology and others.
"Not only have they mapped every single neuron in the insect's brain, but they've also worked out how each neuron is connected. This is a big step forward in addressing key questions about how the brain works, particularly how signals move through the neurons and synapses leading to behaviour, and this detailed understanding may lead to therapeutic interventions in the future."
The next step will be to delve deeper to understand the architecture required for specific behavioural functions, such as learning and decision making, and look at activity in the whole connectome while the insect is doing things.
Winding M, Pedigo BD, Barnes CL et al. The connectome of an insect brain. Science 9 March 2023.
Tags: Brain & Neurology | UK News
Printer
friendly page