Time flows, time flies, time stands still. All these expressions show just how highly variable, depending on multiple factors, our perception of the passage of time can be. How is this subjective experience embodied in the human brain? Scientists in Portugal have begun to unravel this fundamental question. A team of neuroscientists at the Champalimaud Centre for the Unknown, in Lisbon, Portugal, has discovered that the activity of certain neurons in a deep region of the mouse brain can be manipulated to induce the animal to under- or over-estimate the duration of a fixed time interval. In other words, they have, for the first time, identified neural circuitry that modulates judgments of elapsed time -- at least in the mouse brain. These results, which were published in the December 9, 2016 issue of Science by Joe Paton, Ph.D., Principal Investigator of the Learning Lab, Ph.D. student Sofia Soares, and post-doc Dr. Bassam Atallah, offer a neurobiological answer to the long-standing question of how the brain produces such variable estimates of time. And not only that: the results may also help to explain why time seems to fly when we are having fun, or to endlessly stretch when we are bored. The Science article is titled “Midbrain Dopamine Neurons Control Judgment of Time.” The group has been studying the neuroscience of how duration is judged for a number of years now, as part of a larger interest in understanding how the brain learns to link causes with effects even over extended over time periods. However, never has the work felt so personally relevant. Recently, two of Dr. Paton's friends were in a serious accident. "The few hours between when we knew about the accident, and when we knew that they would be ok... felt like weeks.Login Or Register To Read Full Story