A mouse's hippocampus--a brain region associated with short-term memory--goes under the microscope in this photo by University of Texas psychiatrist Neal Melvin.
Melvin had stained the tissue with separate proteins that bind to different parts of the brain. Illuminated by ultraviolet light, the proteins attached to dividing brain cells glowed green. Proteins in areas of mature, active neurons shone red and orange.
Picture by Neal Melvin, courtesy 2008 Olympus BioScapes Digital Imaging Competition