By measuring the speed of smell, researchers at Cold Spring Harbor Laboratory have now found that unlike humans, rats can tell two very similar odors apart with just one sniff. And because it's not the Nose that Knows, but rather the brain, such studies of how animals can rapidly and accurately discriminate odors are revealing vital new information about how the human brain processes information, guides behavior, and even enables us to be consciously aware of our own (though less smelly) world, and our own selves.
"We are trying to understand how systems of neurons participate in the creation of perception, awareness, and behavior," says Cold Spring Harbor Laboratory neuroscientist Zach Mainen, who led the new study.
By exploring the neural mechanisms by which rodents use odors to guide their behavior, Mainen and his colleagues hope to uncover basic principles of brain function that will apply in many settings, including how our own brains work. But to get there, they needed to start out by measuring seemingly strange things such as how many sniffs a rat takes per second. The answer, according to the new study: about eight sniffs per second.
Believe it or not, the "eight sniffs per second" measurement has helped resolve a hotly debated issue in neuroscience. Researchers have previously suggested that the brain requires extra processing time to distinguish among the millions of different chemical signals that can be picked up by the nose. The new study, which appears in the November issue of Nature Neuroscience (advance online publication date: October 20), overturns this conventional wisdom that smell is a slow sense.
"We found that a rat gets
Contact: Peter Sherwood
Cold Spring Harbor Laboratory