Credit: Herrera KJ, Marshall JD, Olveczky BP
In the last decade, Neuroscientists have made major advances in their quest to study the brain. They can assemble complete wiring diagrams and catalogue the brain's many cell types. They've developed electrode arrays for recording electrical activity in individual neurons and placed itty bitty microscopes on the heads of mice to visualize their brain activity. However, almost shockingly, there are no tools to precisely measure the brain's principal output -- behavior - in freely moving animals.
Animal behavior is important to a broad range of disciplines, from neuroscience and psychology to ecology and pharmacology. Carefully studying a lab animal's behavior allows researchers to model human disease and gauge the effectiveness of new drugs. Psychologists observe it to understand how animals learn and respond to reward and punishment, while neuroscientists study it to understand how the brain produces movements. The difficulty in capturing the intricate details of an animal's natural behavior has forced scientists to study very simple and often unnatural tasks, leaving open the question of whether the insights gained can really lead to a general understanding of brain function.