Researchers create detailed map of neural connections in mouse brain

The human brain is so complex that the scientific brain has a hard time understanding it. Nerve tissue, the size of a grain of sand, could be packed with hundreds of thousands of cells connected by miles of wiring. In 1979, Nobel Prize-winning scientist Francis Crick concluded that the anatomy and activity of only a cubic millimeter of brain material would forever surpass our understanding.

“It’s useless to seek the impossible,” says Dr. Crick. I wrote it.

46 years later, a team of over 100 scientists achieved that impossible by recording cell activity and mapping the structure of cubic millimeters of the mouse brain. In achieving this feat, they accumulated 1.6 petabytes of data. This is equivalent to 22 years of non-stop high-resolution video.

“This is a milestone,” said Davi Bock, a neuroscientist at the University of Vermont. the studywas published in the journal Nature on Wednesday. Dr. Bock said that it enabled advances that allowed it to cover the cubic bones of the cubic brain to map the entire brain wiring of a mouse.

“It’s completely doable and I think it’s worth doing,” he said.

Over 130 years It has passed since Spanish neuroscientist Santiago Ramon y Kajal first spies on individual neurons under a microscope, creating a unique branching shape. Scientists from subsequent generations have resolved many of the details about how neurons send voltage spikes into long arms called axons. Each axon makes contact with small branches or dendrites of adjacent neurons. Some neurons excite their neighbors and fire their own voltage spikes. Some quiet other neurons.

Human thinking emerges in some way from this combination of excitation and inhibition. But how this happens remains a ridiculous mystery as scientists could only study a small number of neurons at a time.

Over the past few decades, technological advances have allowed scientists to begin mapping the whole brain. 1986, British researcher Published A small worm circuit made up of 302 neurons. The researchers then charted larger brains, including 140,000 neurons in the fly’s brain.

After all, is Dr. Crick’s impossible dream possible? The US government began in 2016 100 million dollar effort Scan cubic millimeters of mouse brain. The project was called Cortical Network (or Mechanical Intelligence from Microns) and was led by scientists from the Allen Institute of Brain Science, Princeton University, and Baylor School of Medicine.

Researchers have zeroed into part of the mouse’s brain, which receives signals from the eyes and reconstructs what the animal is seeing. In the first phase of the study, the team recorded the neuronal activity in that area as they showed mouse videos of different landscapes.