"Many complex human behaviors ... rely on the brain's ability to accurately tell time," said Dean Buonomano, an associate professor of neurobiology and psychiatry at UCLA's David Geffen School of Medicine. "Yet no one knows how the brain does it."
Buonomano's research suggests a physical model for that ability.
"If you toss a pebble into a lake," he explained, "the ripples of water produced by the pebble's impact act like a signature of the pebble's entry time," he said. "The farther the ripples travel the more time has passed.
"We propose a similar process takes place in the brain that allows it to track time," he added. "Every time the brain processes a sensory event, such as a sound or flash of light, it triggers a cascade of reactions between brain cells and their connections. Each reaction leaves a signature that enables the brain-cell network to encode time."
The study appears in the Feb. 1 issue of the journal Neuron.