For the very first time, scientists have demonstrated that a brain
implant can improve thinking ability in primates. By implanting an
electrode array into the cerebral cortex of monkeys, researchers were
able to restore — and even improve — their decision-making abilities.
The implications for possible therapies are far-reaching, including
potential treatments for cognitive disorders and brain injuries.
But there's also the possibility that this could lead to implants that could boost your intelligence. Here's how they did it.
Mapping minds
Researchers
from Wake Forest Baptist Medical Centre, University of Kentucky, and
University of Southern California took five rhesus monkeys and trained
them on a delayed match-to-sample task. This involved tracking images of
toys, a person, and a mountain range that were flashing on a large
screen. Following a delay, the monkeys had to select the same image on
the screen from a group of one to seven images. The monkeys were trained
to work on this task for the past two years, and they managed to
acquire a proficiency of around 75%.
The
researchers, a team led by Sam Deadwyler and Robert Hampson, then
monitored the brain activity of the monkeys to confirm the location of
the areas required for decision making. They paid particular attention
to those areas that lit up when the monkeys were successful at the
matching game.
To do so,
they used a tiny probe with two sensors that was threaded through the
monkeys' forehead and into their cerebral cortex (specifically between
two cortical layers of the brain), thus allowing them to record activity
in the prefrontal cortex.
Bring on the coke
Once they
were satisfied that the correct mapping had been done, they administered
cocaine to the monkeys to impair their performance on the
match-to-sample task (seems like a rather severe drug to administer, but
there you have it). Immediately, the monkeys' performance fell by a
factor of 20%.
It was at
this point that the researchers engaged the neural device. Specifically,
they deployed a "multi-input multi-output nonlinear" (MIMO) model to
stimulate the neurons that the monkeys needed to complete the task. The
inputs of this device monitored such things as blood flow, temperature,
and the electrical activity of other neurons, while the outputs
triggered the individual neurons required for decision making. Taken
together, the i/o model was able to predict the output of the cortical
neurons — and in turn deliver electrical stimulation to the right
neurons at the right time.
Uplift happens
And
incredibly, it worked. The researchers successfully restored the
monkeys' decision-making skills even though they were still dealing with
the effects of the cocaine. Moreover, when duplicating the experiment
under normal conditions, the monkeys' performance improved beyond the
75% proficiency level shown earlier. In other words, a kind of cognitive
enhancement had happened.
The
researchers hope to apply their findings to treating brain injuries or
diseases where larger areas of the brain have been affected (such as
dementia or stroke). The researchers are confident that their technology
could be contained on an implantable chip.
Looking
ahead to the future, and assuming safety and ongoing efficacy, it may
even be possible to apply a similar intervention to healthy humans.
Which could lead to prosthetically enabled intelligence augmentation.
Their results were published in the Journal of Neural Engineering.
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