The human brain processes information at different speeds depending on the situation, with some signals requiring immediate responses, such as reacting to a sudden sound or movement. Others develop more gradually, allowing the brain time to gather context for a given situation.
However, according to a new study, the brain’s ability to switch between fast and slow processes depends on how its wiring supports communication between regions.
The study from Rutgers University, published in Nature Communications, reports that the brain’s white matter connections are important for bringing together signals that are processed at different speeds. The results help explain why some people move between mental states more easily than others, and why cognitive abilities differ from person to person.
How the Brain Processes Time
Not all parts of the brain process information at the same pace. Researchers refer to these differences as intrinsic neural timescales, or INTs. Regions tied to perception and movement respond rapidly, while areas involved in complex thought combine information more slowly.
“To affect our environment through action, our brains must combine information processed over different timescales,” said lead author Linden Parkes, an assistant professor of psychiatry at Rutgers Health. “The brain achieves this by leveraging its white matter connectivity to share information across regions, and this integration is crucial for human behavior.”
White matter consists of nerve fibers that connect different regions of the brain. These pathways let information move between areas that process things quickly and those that work more slowly, helping organize the networks that support our behavior.
Mapping Brain Wiring
Parkes and his team analyzed brain imaging data from 960 individuals to understand how this merging happens. They created detailed maps of each person’s brain connections, called connectomes, and used mathematical models to describe how these networks change over time.
Instead of measuring neural timescales directly, the researchers estimated them using each region’s pattern of connections. This lets the team connect how a brain area handles information on its own with how it shares information across the whole network.
“Our work probes the mechanisms underlying this process in humans by directly modeling regions’ INTs from their connectivity,” Parkes said. “This draws a direct link between how brain regions process information locally and how that processing is shared across the brain to produce behavior.”
Why Some Brains Switch More Efficiently
The researchers found that cortical neural timescales shape how efficiently the brain shifts between behavior-related activity patterns. This organization was different for each individual.
People whose brain wiring matched well with the processing speeds of different regions were better at switching between mental states. These individuals also performed better overall on cognitive tasks.
“We found that differences in how the brain processes information at different speeds help explain why people vary in their cognitive abilities,” Parkes said.
Grounded in Biology
The study also linked these network patterns to genetic, molecular, and cellular features of brain tissue. Regions with similar timescales share biological traits that shape the timing of brain activity.
The team also examined similar data from mouse brains to determine whether these relationships also exist in other animals. They found the same links between connectivity, processing timescales, and biological features in mice, showing that this mechanism is shared by different species.
Implications for Mental Health
Although the study focused on healthy people, the researchers say this data could also help explain neuropsychiatric disorders. Conditions like schizophrenia, bipolar disorder, and depression frequently include problems with large-scale brain connections.
Researchers are now studying how changes in white matter might disrupt the brain’s ability to combine information at different speeds, and how those disruptions could relate to symptoms.
The study was conducted in collaboration with Avram Holmes of Rutgers Health, along with postdoctoral researchers Ahmad Beyh and Amber Howell, and Jason Z. Kim of Cornell University.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds a Master of Business Administration, a Bachelor of Science in Business Administration, and a Data Analytics certification. His work combines analytical training with a focus on emerging science, aerospace, and astronomical research.