The degree to which networks of activity in the brain reconfigure themselves while switching from one task to another decides why some people are better at multi-tasking, reveals research.
The participants who performed best while alternating between a memory test and a control test showed the most rearrangement of connections within brain's frontal cortices as well as the most new connections with other areas of their brains.
Looking for the mechanisms behind cognitive flexibility, researchers at the University of Pennsylvania, Germany's Central Institute of Mental Health and Charite University Medicine Berlin used brain scans to shed new light on this question.
A more fundamental understanding of how the brain manages multitasking could lead to better interventions for medical conditions associated with reduced executive function, such as autism, schizophrenia or dementia.
"Rather than being driven by the activity of single brain areas, we believe executive function is a network-level process," said senior study author Danielle Bassett from University of Pennsylvania.
A previous study that Bassett led showed that people who could more quickly "disconnect" their frontal cortices did better on a task that involved pressing keys that corresponded to color-coded notes on a screen.
The high level decision-making associated with the frontal cortex's cognitive control was not as critical to playing the short sequences of notes, so those who still engaged this part of the brain were essentially overthinking a simple problem.
"The nodes in the network that are most involved in reconfigurations are cognitive control areas in the frontal cortex," Bassett said.
"More flexibility within the frontal cortex meant more accuracy on the memory task, and more consistent connectivity between the frontal cortex and other regions was even more predictive," he added.
The study was published in the journal Proceedings of the National Academy of Sciences