Brain scans show optimal times for multitasking
17 September 2008
Multitasking has become an increasingly necessary part of our daily
lives, but it is a notoriously inefficient way of working. However, a
new brain imaging study led by a cognitive neuroscientist at the
University of New Hampshire finds that there are optimal times when we
are better suited to multitask.
In the study “Neural predictors of moment-to-moment fluctuations in
cognitive flexibility” published in the latest issue of the
Proceedings of the National Academy of Sciences, Andrew Leber,
assistant professor of psychology at UNH, explains how the brain can act
as crystal ball to predict when people are efficient multitaskers.
“We typically sacrifice efficiency when we multitask. However, there
are times when we’re quite good at it. Unfortunately, not much has been
known about how to predict when these periods of time will occur,” Leber
While having the study participants multitask, Leber and his
colleagues at Yale University monitored their brain activity using
functional magnetic resonance imaging (fMRI). The research confirmed
that multitasking is, on average, inefficient. However, the brain scans
allowed the researchers to predict when people would be poor
multitaskers and optimal multitaskers.
Most dramatically, the changes in performance were preceded by
changes in the participants’ brain activity patterns. Higher levels of
activity in brain regions such as the basal ganglia, anterior cingulate
cortex, prefrontal cortex, and parietal cortex corresponded to better
“What is so striking about this result is that brain activity
predicted multitasking performance before participants even knew whether
they would be asked to switch or repeat tasks,” Leber said.
Being able to predict when people are in optimal multitasking states
raises tantalizing prospects for maximizing productivity in our daily
lives, according to Leber. Ideally, we should reserve task juggling for
known periods of optimal multitasking while doing repetitive tasks
during known periods of poor multitasking.
Yet, while the brain imaging results reflect a critical step in
helping us to better schedule our daily routine, they don’t provide a
truly practical solution quite yet. “Obviously, the average person can’t
bring an fMRI scanner to work,” Leber said. “It may take more time
before our research translates to real-world benefits for each of us.”
Nevertheless, he believes that the current study represents a
“The fact that we are able to so rapidly switch from one task to
another is no accident of nature, as it reflects an enhanced capacity to
flexibly interact with our environment. And, it’s to our benefit to
exercise this remarkable skill from time to time, although the key might
be to keep it in moderation,” he said.
The research also may inform scientists’ understanding of
neurological disorders, such as Parkinson’s disease, which is marked by
degeneration of the basal ganglia. While it is commonly known that
Parkinson’s patients experience deficits in controlling movement,
multitasking also is adversely affected.
“We’ve known that multitasking suffers when the physical makeup of
the basal ganglia degenerates over time, as in Parkinson’s disease,”
Leber said. “However, the current study shows that even in healthy
adults, short-term changes in the basal ganglia also impact
This observation opens new potential avenues in studying normal brain
functioning to help provide a more complete picture of the disordered
functioning in Parkinson’s disease.