Scientists at Seattle's Allen Institute for Brain Science have completed the first comprehensive map of a mammalian brain, marking an important step in the quest to understand still-mysterious brain diseases like autism, Alzheimer's, and Parkinson's.
The achievement was announced on Apr. 2 in the journal Nature Neuroscience.
While plenty of diseases are difficult to treat, brain diseases often stymie the medical community completely because they are challenging to even understand. In part, that's because the human brain — which has an estimated 86 billion neurons — is densely packed and intricately connected, making it almost mind-numbingly complex.
A map showing the connections that run all throughout the brain had only been completed before in a tiny, primitive roundworm with about 302 neurons. A mouse has 71 million.
The publicy available map documents all of the cellular connections in a healthy mouse brain. This foundation will allow researchers to examine what is different in a diseased brain, and to begin to develop animal models of brain diseases — an important tool for medical research.
"It has been hypothesized that connectivity changes may be one of the major underlying causes of diseases" like autism, Alzheimer's and Parkinson's, Hongkhui Zeng of the Allen Institute told Business Insider. "Once we know where [those changes] are, we can think about how to treat them."
MORE IMAGES: Here's How They Made The Mouse Brain Map