Largest fragment of the human brain mapped

Researchers from Harvard University and Google published the largest synaptic resolution and 3D reconstruction of a slice of human brain to date.

The cubic millimeter of brain tissue is about half the size of a grain of rice, but contains 57,000 cells, 230 mm of blood vessels and 150 million synapses.

The resulting digital reconstruction amounts to 1,400 terabytes of data. It is described in a new article in the journal Science.

“The word ‘fragment’ is ironic,” says Jeff Lichtman, professor of molecular and cellular biology at Harvard University, who led the study.

“A terabyte is huge for most people, but a fragment of a human brain – just a tiny piece of human brain – is still thousands of terabytes.”

The research is the result of a nearly decade-long collaboration between Lichtman’s team and scientists from Google Research, who combine Lichtman’s electron microscopy images with AI algorithms to color and reconstruct mammalian brains in three dimensions.

Their ultimate goal is to create a high-resolution map of a mouse’s entire brain.

This area of ​​research studies the ‘connectome’ which is defined as the ‘complete, point-to-point spatial connectivity of neural pathways in the brain’.

Creating a comprehensive catalog of brain structure, down to individual cells, could provide new insights into brain function and disease.

“Given the enormous investment that went into this project, it was important to present the results in a way that everyone can benefit from now,” said co-author Viren Jain, a research scientist at Google Research.

The authors are: “sharing all the data in an online resource and providing tools for analysis and proofreading.”

The next step is the formation of the hippocampus in mice, which is important to neuroscience because of its role in memory and neurological diseases.