Neuroscientist Leslie Tolbert explains the brain's geography.

"The brain is the most complicated object on earth," says Leslie Tolbert, and she should know. The University of Arizona neuroscientist has studied the brain and its development for decades, using the imaging technologies that have developed in that time to probe the organ's structure and life-cycle.

"The tools that have come into use in the last 30 years have completely revolutionized the kinds of questions we an ask,” she says.

Tolbert's recent research owes its insights to a different kind of tool: an insect model. She and her team are studying the olfactory system, or the sense of smell, of the Manduca moth to learn how the brain's variety of cells interact and what roles they play.