This technology illuminates the entire "dark forest" of the brain neural network structure

The neural circuit of the human brain is an extremely complex and huge network, containing tens of billions of nerve cells.

With the development of technology, the mystery of the brain neural network structure is gradually being unveiled

However, if an animal’s brain is compared to a vast forest, there is currently no technology that can see every tree (nerve cell) in the entire forest at the same time and distinguish each leaf (nerve) on the tree.

The resolution of MRI and PET is too low, only the community of trees can be seen, and individual trees cannot be identified

In order to solve this extremely challenging problem, Zhang Ruobing's research group from Suzhou Institute of Biomedical Engineering Technology, Chinese Academy of Sciences proposed an innovative optical imaging method, Optical Multilayer Interference Tomography (OMLIT), which can be used in the introduction.

The research team designed, constructed, and carefully tested a series of multi-thin layer structures, including conditions such as different substrate materials, coating materials, coating thickness, and ultra-thin brain tissue sample thickness, and found several multi-thin layers that optimize the imaging results.

The researchers established a theoretical model of multiple reflections and interference of light waves between different thin-layer media to form high-contrast images of all cells in the ultra-thin section sample (Figure 4), which explains and simulates this imaging phenomenon well

OMLIT makes it possible to quickly reconstruct the morphology, distribution and projection maps of all nerve cells at mesoscopic resolution, and can seamlessly connect to continuous tomographic scanning electron microscopy (sSEM) to achieve whole-cell optics on the same animal brain tissue sample Imaging and electron microscopy imaging

For the first time, this study achieved mesoscopic resolution optical imaging and micro-resolution electron microscopy imaging of all cells in the same brain tissue sample

Under the constraints of current imaging technology and image processing capabilities, due to the huge time consumption and data volume, it is unrealistic to simply use sSEM to draw a global micro-resolution neural connection group map

Related results have been published online on ACS Photonics with the title Optical Multilayer Interference Tomography Compatible with Tape-Based Serial SEM for Mesoscale Neuroanatomy, and have been selected as the cover of the supplementary journal

Link to the paper: https://pubs.

Source: Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences