An international team of scientists has created the largest 3D wiring diagram for a mouse brain. The goal is to study the principles of the brain that can contribute to the progress of artificial intelligence.
The presented map shows the complex structures and connections of about 200 thousand brain cells and almost 500 million synapses. All of them are hidden in a cubic millimeter of a mouse brain the size of a grain of sand.
What’s more, the dataset is unique in that it includes recordings of patterns of activity triggered by a variety of complex visual stimuli, from YouTube clips to Hollywood movies. During the experiment, it was activated for about 75 thousand brain cells.
The map and dataset are now publicly available.
It took five years to create the map. In the course of the work, the scientists focused their research on the visual neocortex. This area of the brain is critical for visual perception. In the first phase, the researchers collected measurements of the typical brain activity of the mouse while it was still alive and created more than 70,000 images of active brain cells.
The scientists then cut out a small piece of the brain and cut it into more than 25,000 ultra-thin pieces. As a result, the researchers captured more than 150 million high-resolution images of these fragments using electron microscopy.
The research is part of the Machine Intelligence from Cortical Networks (MICrONS) program, which aims to improve machine learning and AI algorithms by reverse-engineering the cerebral cortex. It is known to be responsible for more complex functions such as planning and reasoning in mammals.
The map will be “invaluable” for neuroscientists trying to figure out how the brain processes information along with neocortical circuits, the researchers said.