Researchers hope their map of a baby fruit fly’s brain will demystify secrets of the human mind
This article was first published in the May/June 2023 issue of IQ, the exclusive magazine for British Mensa members packed with engaging and stimulating stories and features.
Scientists from Johns Hopkins University in Baltimore and the University of Cambridge generated quite a buzz in March [this year] when they published the first complete map of a baby fruit fly’s brain. The research took 12 years to finish and marks a significant breakthrough in understanding the mechanisms of thought.
For decades, scientists have been constructing neurological maps to try to make sense of the complex structures and processes of the brain, with partial maps being created for the brains of worms, flies, mice, and even humans – but no complete map has previously been produced.
The research produced an astonishing depiction of the brain of a fruit fly larva, which is made up of 3,016 neurons and more than half a million neural connections. The scientists took high-resolution images of the fly larva’s brain using an electron microscope and linked each neuron to its connections. This data was then analysed using original code created by the researchers to identify likely pathways of information flow and circuit patterns. The team managed to chart every neuron and every neurological connection, categorising each neuron by the role it plays.
It is hoped that the methods developed will be applicable to studying the brains of larger animals, including humans. Fruit flies share fundamental biology and genetic foundations with humans, making their tiny brains a perfect starting point for unlocking remaining mysteries of the human mind. There is still a lot of work to be done in brain cartography, and the scales involved are mind-boggling.
The next milestone will be mapping the brain of a mouse, which is roughly a million times bigger than that of a baby fruit fly. For context, a mouse’s brain contains roughly 70 million neurons, while the human brain is thought to contain a whopping 86 billion – so a detailed map of the human brain is unlikely to be completed anytime soon.
In addition to neurology, the work is likely to inspire advancements in the field of machine learning thanks to striking resemblances identified between the circuit features of the fruit fly brain and state-of-the-art, machine-learning architectures. The team expects further study in this area will contribute to our understanding of computational principles and may even inspire new artificial intelligence systems.
Inside the mind of an insect
Check out this 3D image of an insect brain’s complete set of neurons, posted by Johns Hopkins University.