Summary: Each person has a specific brain “fingerprint”, and that fingerprint changes over the course of our lives, a new study reports.
Source: EPFL
“I
think about it every day and dream about it at night. It’s been my
whole life for five years now,” says Enrico Amico, a scientist and SNSF
Ambizione Fellow at EPFL’s Medical Image Processing Laboratory and the
EPFL Center for Neuroprosthetics.
He’s
talking about his research on the human brain in general, and on brain
fingerprints in particular. He learned that every one of us has a brain
“fingerprint” and that this fingerprint changes over time.
His findings have just been published in Science Advances.
“My
research examines networks and connections within the brain, and
especially the links between the different areas, in order to gain
greater insight into how things work,” says Amico.
“We do this largely using MRI scans, which measure brain activity over a given time period.”
His
research group processes the scans to generate graphs, represented as
colorful matrices, that summarize a subject’s brain activity. This type
of modeling technique is known in scientific circles as network
neuroscience or brain connectomics.
“All
the information we need is in these graphs, commonly known as
“functional brain connectomes.” The connectome is a map of the neural
network. It reveals what subjects were doing during their MRI scan—if
they were resting or performing some other tasks, for example. Our
connectomes change based on what activity was being carried out and what
parts of the brain were being used,” says Amico.
Two scans are all it takes
A
few years ago, neuroscientists at Yale University studying these
connectomes found that every one of us has a unique brain fingerprint.
Comparing the graphs generated from MRI scans of the same subjects taken
a few days apart, they were able to correctly match up the two scans of
a given subject nearly 95% of the time. In other words, they could
accurately identify an individual based on their brain fingerprint.
“That’s
really impressive because the identification was made using only
functional connectomes, which are essentially sets of correlation
scores,” says Amico.
He
decided to take this finding one step further. In previous studies,
brain fingerprints were identified using MRI scans that lasted several
minutes. But he wondered whether these prints could be identified after
just a few seconds, or if there was a specific point in time when they
appear—and if so, how long would that moment last?
“Until
now, neuroscientists have identified brain fingerprints using two MRI
scans taken over a fairly long period. But do the fingerprints actually
appear after just five seconds, for example, or do they need longer? And
what if fingerprints of different brain areas appeared at different
moments in time? Nobody knew the answer. So we tested different time
scales to see what would happen,” says Amico.
A brain fingerprint in just 1 minute and 40 seconds
His
research group found that seven seconds wasn’t long enough to detect
useful data, but that around 1 minute and 40 seconds was. “We realized
that the information needed for a brain fingerprint to unfold could be
obtained over very short time periods,” says Amico.
“There’s no need for an MRI that measures brain activity for five minutes, for example. Shorter time scales could work too.”
His
study also showed that the fastest brain fingerprints start to appear
from the sensory areas of the brain, and particularly the areas related
to eye movement, visual perception and visual attention. As time goes
by, also frontal cortex regions, the ones associated to more complex
cognitive functions, start to reveal unique information to each of us.
The next step will be to compare the brain fingerprints of healthy patients with those suffering from Alzheimer’s disease.
“Based
on my initial findings, it seems that the features that make a brain
fingerprint unique steadily disappear as the disease progresses,” says
Amico.
“It
gets harder to identify people based on their connectomes. It’s as if a
person with Alzheimer’s loses his or her brain identity.”
Along
this line, potential applications might include early detection of
neurological conditions where brain fingerprints get disappear. Amico’s
technique can be used in patients affected by autism, or stroke, or even
in subjects with drug addictions. “This is just another little step
towards understanding what makes our brains unique: the opportunities
that this insight might create are limitless.”
About this neuroscience research news
Author: Press Office
Source: EPFL
Contact: Press Office – EPFL
Image: The image is credited to Enrico Amico
Original Research: The findings will appear in Science Advances