To Leaf Through a Brain

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0.002362204724409449 inches at a time

The brain has to be carefully prepared in order for us to examine its minute features, such as nerve cells and their processes that are the basis for mental function. Each brain is preserved by chemical fixation, hardened, frozen en block, and sliced into thousands of very thin and semi-transparent slices.

Ever since Leonardo da Vinci, observing an object in cross-section has been the method of choice in anatomy. That is where the name "tomography" comes from. We believe that if we want to understand how such a complex biological mechanism as the brain works we have to study it as a whole. We have built specialized equipment and pioneered techniques to be able section the entire brain and recreate its original shape as a digital model. We routinely use large-format glass slides and custom-engineered imaging equipment to digitize each section down to cellular resolution.

In practice, each brain becomes a stack of giant sections that are stained according to different protocols to show different aspects of the tissue. In the background, for example, a "modified" silver stain developed in our laboratory shows even the finest fibers that connect different structures in the brain. Even though brain structures are specialized for different functions, and are thus involved in different neruological disorders, they do not work independently but are linked by specialized networks. We have, therefore, trained and invested considerable resources to be able to illustrate the inner structure of the whole brain at microscopic resolution.