Karl R. Koehler, Indiana University School of Medicine
It might not look like much at first, but this is an artificial ear. Well, part of it at least. Scientists used stem cells in a petri dish to create a model of the cells behind your sense of hearing. Hair cells, labeled in red, pick up vibrations in your ear through hair cell bundles, marked in yellow, and transform that information into electrical signals. Your brain uses those signals to create sounds. Scientists use artificial models like this to study individual cells and circuits, and determine how they interact in healthy — and unhealthy — people. One of these ears might help us new therapies for deafness, hearing loss, and other disorders of the ear.