Researchers Explain How Brain Measures Time
Ever wondered what would happen if did not have a watch? Wondered how after a couple of days of waking up at a specific time in the morning, how the body programmes itself to wake up at the same time without an alarm clock? Well, the brain certainly has a sense of time and can measure time even without the help of a clock.
Researchers at the University of Minnesota's Center for Magnetic Resonance Research (CMRR) have been working to find how the brain measures time, and have found a small population of neurons that is involved in the process that has traditionally been difficult to study in the lab.
For the study, the researchers designed a task for which monkeys had to rely only on their internal sense of the passage of time.
For the experiment, the researchers eliminated all external cues that could have served as "clocks".
The monkeys were trained to move their eyes consistently at regular time intervals without any external cues or immediate expectation of reward. The findings of the observation revealed that monkeys could solely depend on their own instincts to accomplish the remarkably precise and consistently timed behavior. This consistency could be explained by activity in a specific region of the brain called the lateral intraparietal area (LIP), Medical Xpress reported.
"In contrast to previous studies that observed a build-up of activity associated with the passage of time, we found that LIP activity decreased at a constant rate between timed movements," said lead researcher Geoffrey Ghose, Ph.D., associate professor of neuroscience at the University of Minnesota.
"Importantly, the animals' timing varied after these neurons were more or less, active. It's as if the activity of these neurons was serving as an internal hourglass."
With the help of a model that explains the differences in timing signals, researchers found that their study also suggests an absence of a "central clock" in the brain that helps in all tasks involving timing. Instead, it appears as though each of the brain's circuits responsible for different actions are capable of independently producing an accurate timing signal, the report said.
This study paves way for another important aspect that could be researched upon. Scientists could further explore how such precise timing signals arise as a consequence of practice and learning, and if the signals are altered, will there be also an effect on behavior.
The study was published on October 30, in the open access journal PLOS Biology.