Adult fruit fly brain (IMAGE) Princeton University Caption For many heartbreaking diseases of the brain — dementia, Parkinson’s, Alzheimer’s and others — doctors can only treat the symptoms. Medical science does not have a cure. Why? Because it’s confounding to cure what we don’t understand, and the human brain, with its millions of neurons connected by a hundred trillion synapses, is almost hopelessly complex. A Princeton-led team of neuroscientists has now made a massive step toward understanding the human brain, by building a neuron-by-neuron and synapse-by-synapse roadmap — scientifically speaking, a “connectome” — through the brain of an adult fruit fly (Drosophila melanogaster). This image is a video still showing the brain inside an adult fruit fly. The full video is available by request to flywire@princeton.edu. Credit Amy Sterling / FlyWire / Princeton University Usage Restrictions Editorial use only License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.