A Wiring Diagram of the Brain
November 19, 2007. By Emily Singer
This movie shows the structure of part of the rabbit retina called the inner plexiform layer, the piece of neural tissue at the back of the eye that senses light and sends visual information to the brain. The long, thin branches of neurons, or neurites, are tangled up like spaghetti. A new technique called serial block face-scanning electron microscopy was used to obtain a series of two-dimensional cross-sectional images of the tangle, shown here in black and white. The resulting 3-D image was analyzed with computer algorithms developed by the researchers using machine-learning methods. First, the tracing of a single neurite is shown in green. Then a larger subset of neurites is shown in multiple colors. The computerized 3-D reconstruction method is still under development and requires the oversight of a human operator to correct errors.
The team that worked on this project included researchers from the Max Planck Institute for Medical Research (Kevin Briggman, Moritz Helmstaedter, and Winfried Denk), MIT and the Howard Hughes Medical Institute (Viren Jain, Joseph Murray, Srini Turaga, and Sebastian Seung).