There is something extraordinary about the mouse brain. This small, half-a-cubic centimeter, corn chip-shaped organ holds nearly 85 million neurons — and the potential to better understand our own brains.
Despite its size, scientists unveil the secrets within this tiny structure daily. A team of researchers at the Allen Institute for Neural Dynamics, a division of the Allen Institute, is taking a closer look at these mini marvels by employing expansion microscopy, a technique that makes the brain three times bigger and see-through with the unlikely assistance of a chemical commonly found in disposable diapers.
Scientists at the Massachusetts Institute of Technology first used the water absorbing chemical, known as sodium polyacrylate, to expand cells and slices of tissue. The Allen Institute team is now using such technology to expand entire mouse brains in a first-of-its-kind approach. By expanding whole mouse brains before capturing images of them, the scientists can see individual axons, the long signal-sending branches of neurons, at a much higher resolution. This is especially important for the types of neurons the Allen Institute team wants to study, which have branches that can stretch multiple centimeters in the brain but are a thousand times thinner than a human hair.
