McGill. Can: Our ability to pay attention to certain things while ignoring
distractions determines how good we are at a given task, whether it is
driving a car or doing brain surgery. A research team at McGill
University has for the first time convincingly identified a network of
neurons in a particular area of the brain, the lateral prefrontal
cortex, that interact with one another to promptly filter visual
information while at the same time ignoring distractions. It’s a
discovery with potentially far reaching implications for people who
suffer from diseases such as autism, ADHD and schizophrenia.
The researchers recorded brain activity in macaques as they moved their
eyes to look at objects being displayed on a computer screen while
ignoring visual distractions. These recorded signals were then input
into a decoder running on a personal computer which mimicked the kinds
of computations performed by the brain as it focuses. With some
startling results.
“The decoder was able to predict very consistently and within a few
milliseconds where the macaques were covertly focusing attention even
before they looked in that direction,” says Julio Martinez-Trujillo, of
McGill’s Department of Physiology and the lead author of the paper. “We
were also able to predict whether the monkey would be distracted by some
intrusive stimulus even before the onset of that distraction.”
But what was even more interesting was that the researchers were able
to manipulate the computer’s ability to “focus” by subtly manipulating
the neuronal activity that had been recorded and input into the machine.
In effect, by manipulating the interactions of the neurons, the
researchers were able to induce “focused” and “distracted” states in the
computer.
“This suggests that we are tapping into the mechanisms responsible
for the quality of the attentional focus, and might shed light into the
reasons why this process fails in certain neurological diseases such as
ADHD, autism and schizophrenia,” says Sébastien Tremblay, a doctoral
student at McGill University and the first author of the paper which was
published in the current edition of Neuron. “Being able to
extract and read the neuronal code from higher-level areas of the brain
could also lead to important breakthroughs in the emerging field of
neural prosthetics, where people who are paralysed use their thoughts to
control objects in their environment.”
Prof. Martinez-Trujillo is now at the Robarts Research Institute at
Western University. This research was done while he was at McGill
University.
To read the full article in Neuron: http://www.cell.com/neuron/abstract/S0896-6273(14)01073-3