Study reveals details about intricate visual network shapes in mice

Study reveals details about intricate visual network shapes in mice

A new study in mice has revealed never-before-seen details about how the intricate visual network forms within them. This research could inform future research into the treatment of congenital blindness. But given the parallels between biological neural tissue and digital artificial intelligence, this research could also help software developers create better and more universal artificial intelligences.

If you could see the web-like nature of the neurons and structures that make up the brains and sensory systems of animals, you might think it was just a random, complicated mess. But researchers such as neuroscientists can look at this chaos and not only derive discrete structures, but also determine their functions. Recently, Professor Kenichi Ohki and Assistant Professor Tomonari Murakami from the Department of Physiology at the University of Tokyo and their team studied a particular formation to learn how it forms -; the vision system.

The eyes, certain parts of the brain and the neural network connecting them form the visual system. A rough analogy might be a camera connected by a cable to a screen that your conscious self can observe. But an accurate biological description of this system is extremely complicated.”

Tomonari Murakami, Assistant Professor, Department of Physiology, University of Tokyo

Murakami adds: "There are a large number of visual cortical areas arranged in layers that form a kind of hierarchical structure. This idea is not new, but it was not known how connections exist between the early stages of this network, or primary areas and areas involved in processing visual signals, or higher visual cortical areas, form during development. We wanted to find out how this happens.”

The team studied the developing visual systems of mice. In particular, they looked at areas called cortical and thalamic regions. By observing how networks of neurons in these regions developed in newborn mice and when these networks became active, the team was able to more generally describe the mechanisms that control the growth of the visual system.

“As we mapped the ever-dense network of connections in time, something jumped out that surprised us,” Murakami said. "We expected the visual network to form many connections between cortical areas first, reflecting the hierarchical structure of the entire system. But in fact, parallel neural pathways from the retina in the eyes leading to the cortical areas form earlier than this." between cortical areas. This new fact changes what we know about this area of ​​cortical development.”

This study was conducted not only to satisfy curiosity, but also because basic research of this kind can form the basis of future medical research that can improve people's lives: in this case, the team's hypothesis that their research on mice can likely explain visual development in primates, including humans. And this, in turn, could help researchers who want to treat congenital blindness.

“There is another area of ​​research that can also learn from what we did here,” Ohki said. "Artificial intelligence is often based on digital artificial neural networks. These are usually structured in multiple layers, which can give them complex functions. But now that we have shown that at least some biological neural systems develop parallel structures before multi-layered ones, software engineers could be inspired to experiment with new design methods. It is conceivable that this will help them with theirs The goal could help to create increasingly universal intelligences capable of solving a wide range of problems.

Source:

University of Tokyo

Reference:

Murakami, T., et al. (2022) Modular strategy for developing the hierarchical visual network in mice. Nature. doi.org/10.1038/s41586-022-05045-w.

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