These images show the head, brain and eyes of a planarian flatworm. Planarian flatworms are animals with the amazing ability to rapidly regenerate and replace all parts of their body, including a brain and central nervous system. A decapitated planarian will regenerate its entire head, brain and eyes in a matter of days! The secret to regeneration is a population of stem cells that surround the brain (orange in this image) and fuel the production of new brain tissue from scratch.

We seek to understand how nature has solved the problem of regenerating, repairing and rewiring a central nervous system. Unlike humans, planarian flatworms complete these tasks with great precision and rapidity after any injury, making them an excellent model for approaching this problem. This image highlights the complexity of our challenge, and the beauty of this biological system. We took this image to visualize the nervous system and its contributing stem cells.