A new study in mice has revealed never-before-seen details of how their complex visual network is formed. This study could inform future research into the treatment of congenital blindness. But given the parallels between biological neural tissue and digital artificial intelligence, this research may also help software engineers develop better and more versatile artificial intelligence.
If you could see the network-like nature of the neurons and structures that make up the brains and sensory systems of animals, you might think it’s just a random, complex mess. But researchers such as neuroscientists are able to look at this chaos and deduce not only individual structures, but also find out their functions. Recently, Professor Kenichi Oki and Associate Professor Tamanari Murakami from the Department of Physiology at the University of Tokyo and their team studied a particular formation to learn how it is formed – the visual system.
“The eyes, some parts of the brain and the neural network connecting them form the visual system. A rough analogy might be a camera connected by a wire to a screen that your consciousness can observe. But the exact biological description of this system is extremely difficult,” said Murakami. “There are a large number of visual areas in the cerebral cortex, and they are arranged in layers that form a kind of hierarchical structure. This idea is not new, but it was unknown how connections between the early stages of this network or primary areas, and areas involved in the processing of visual signals, or higher areas of the cerebral cortex are formed during development. We decided to find out how it happens.”
The team studied the visual systems of developing mice. Specifically, they looked at areas called the cortical and thalamic regions. By seeing how the networks of neurons in these regions developed in newborn mice and when those networks became active, the team was able to more generally describe the mechanisms that regulate the growth of the visual system.
“As we captured an increasingly dense network of connections in time, something jumped out that surprised us,” Murakami said. “We expected that the visual network would first form many connections between cortical areas, reflecting the hierarchical structure of the entire system. But in reality, the parallel neural pathways from the retina in the eyes that lead to areas of the cerebral cortex are formed earlier than those among the areas of the cerebral cortex. This new finding changes what we know about this area of cortical development.”
This study was conducted not only to satisfy curiosity, but also because basic research like this can form the basis of future medical research that can improve people’s lives: in this case, the team’s hypothesis that their research in mice can explain the development of vision in primates including man. And this, in turn, can help researchers who seek to cure congenital blindness.
“There’s another area of research that can learn from what we’ve done here,” Oki said. “Artificial intelligence is often based on digital artificial neural networks. They are usually structured in several layers, which can give them complex functionality. But now that we have shown that at least some biological neural systems develop parallel structures before multilayers, software engineers can gain from “This is the inspiration for experimenting with new design methodologies. It’s possible that this could help them achieve their goal of creating even more general-purpose intelligence capable of solving a wide range of problems.”