Until now, neuroscientists typically had to cut a brain into ultra-thin slices to visualize such features. But that chops up one of the things they’re most interested in studying: the cable-like axons that carry signals from one part of the brain to another. The new method makes it possible to visualize these long-range connections as well as the fine-scale anatomy and molecular make up of neurons, the scientists report today in Nature.
Although they developed the method in mouse brains, the team shows that it works on human post-mortem brain tissue too. In the Nature paper, they describe abnormal neural connections in an autistic boy whose brain had been stored in formalin for more than 6 years.