Public Library of
Science - Computational Biology
Brain noise is a good thing
Canadian study overturns notion that brain noise quiets
down with maturity in adulthood
Toronto, Canada – Canadian scientists have shown that
a noisy brain is a healthy brain.
“Brain noise” is a term that has been used by
neuroscientists to describe random brain activity that is not important to
mental function. Intuitive notions of
brain-behaviour relationships would suggest that this brain noise quiets down
as children mature into adults and become more efficient and consistent in
their cognitive processing. But new research from the Rotman Research Institute
at Baycrest, published in the July 4, 2008 issue of the Public Library of Science - Computational Biology, overturns this
notion.
“What we discovered is that brain maturation not only leads
to more stable and accurate behaviour in the performance of a memory task, but
correlates with increased brain signal
variability,” said lead author, Dr. Randy McIntosh, a senior scientist with the
Rotman Research Institute at Baycrest. “This doesn’t mean the brain is working
less efficiently. It’s showing greater functional variability, which is
indicative of enhanced neural complexity.”
In the study, 79 participants representing two main age groups
– children (eight to 15) and young adults (20 to 33 years of age) – completed a
series of face memory tasks to measure their ability to recall faces with
accuracy. EEG recordings were collected to measure their brain signal activity
while performing the task. EEG – electroencephalography – is a powerful brain
imaging tool that allows for precise measurement of the timing of brain activity
in response to external stimuli.
Researchers found that not only did the young adults score
better on the face recognition tasks (ie. they showed more stable and accurate
cognitive behaviour) compared to the children, but the young adults’ brain
signal variability actually increased – got noisier. These findings suggest
that the random activity that we think of as “noise” may actually be a central
component of normal brain function, said
Dr. McIntosh.
The study was funded by the James S. McDonnell Foundation. Baycrest is an academic health sciences centre, internationally-renowned
for its care of aging adults and its excellence in aging brain research,
clinical treatments and promising cognitive rehabilitation strategies. Baycrest
is fully affiliated with the University
of Toronto.
To view the article:
http://dx.plos.org/10.1371/journal.pcbi.1000106
For more information on this press release, please
contact:
Kelly Connelly
Senior Media
Officer
Rotman Research
Institute at Baycrest
416-785-2432
kconnelly@baycrest.org