Neuroscientists have generally believed the brain has a centralized clock responsible for keeping time, a task that is essential for activities such as playing a musical instrument or swinging a baseball bat.
But a team of researchers at the Massachusetts Institute of Technology say that’s not necessarily true, suggesting the brain is more dynamic than previously thought.
Scientists have yet to find solid evidence for the centralized clock theory, so the MIT team wondered if the different parts of the brain responsible for actions like playing an instrument or sport might keep time in a different way, the university said in a statement.
“People now question why would the brain want to spend the time and energy to generate a clock when it’s not always needed,” Mehrdad Jazayeri, a life science professor at MIT, a member of the university’s brain research institute, and the senior author of the study, said in the statement.
To answer this question, the researchers had animals perform basic tasks at two different time intervals and simultaneously recorded neuron activity from three regions of their brains.
To perform a certain behavior, neurons must go from one state to another, changing as they fire, or send impulses to one another, Jazayeri said.
Instead of passively waiting for a clock to reach a certain point, the team found the system of neurons changes its state independently based on the action being performed.
Jazayeri explained this system with a metaphor. Think of a pebble hitting the surface of a lake, creating a pattern of ripples of the water. Those ripples represent the activity of neurons as they fire, he said.
Just as factors such as the size of the pebble would change the pattern of the ripple, the firing rate, which depends on the action being performed, changes the state of the neurons.
“That pattern, at any point in time, changes, which means I can look at that pattern and tell how much time has passed,” Jazayeri said in a telephone interview Monday. “It seems to be the system is actively using information about time in the context of behavior.”
The latest discovery might actually make it easier for those outside of the scientific community to understand how the brain works, since it deviates from the explanation that the brain functions like a computer does, Jazayeri said.
“It’s important that maybe the brain’s not entirely like that,” he said.
“In this day and age, it becomes particularly relevant because the world is rapidly changing in the direction of creating artificial intelligence,” he said, so the language of computers is becoming increasingly important, especially in relation to human thoughts and memories.