- THURSDAY, Aug. 7 (HealthDay News) — Scientists say they're
gaining insight into how the brain rewires itself as it learns new things,
potentially helping them move toward better treatments for mental illness
and brain injuries.

Researchers report that a protein appears to tell the brain that it's
time to start rewiring, because new information is coming in.

While the study only looked at mice, the protein “could become a great
clinical tool” in humans, said study co-author Takao Hensch, a professor
of neurology at Children's Hospital Boston.

At issue is the brain's “plasticity,” or ability to change itself as it
learns. The brains of young children are the most adaptable, because they
can physically rewire themselves.

“You actually have neurons reconnecting from one cell to a different
cell,” Hensch said. “This kind of dramatic rewiring happens predominantly,
if not exclusively, in [early] development.”

The brain's ability to adapt to new information explains why children
have a much easier time learning languages than adults, Hensch said.

But over time, the brain becomes more settled in its ways. “The ability
to rewire neurons in that physical way seems to become much harder with
age,” he said. “Evolutionarily, somehow it seems to be advantageous to
stop that process, to stabilize the networks in your head and go on with
life.”

In the new study, published in the Aug. 8 issue of Cell, Hensch
and colleagues looked at a protein called Otx 2 in mice.

Using a test involving the visual system, the researcher found that the
protein acts as a signal to tell the brain that crucial information is
coming in from the eyes.

“It's a surprising mechanism,” he said. “It indicates that the sensory
organs in the periphery — the eyes at the front of the head — have a
mechanism to tell the brain when the eyes are ready and actually seeing
something meaningful.”

If scientists understand the protein's function correctly, it could
mean that “every sensory system has some kind of message to send to the
brain to make it plastic at some time,” Hensch said.

It's possible that researchers could develop a way to “turn on” brain
plasticity in older people, such as those with mental illness or brain
injuries. Since the Otx 2 protein sends signals from the eyes, it may be
possible to give treatments through eyedrops, Hensch said.

The findings are important and “start to tell us how external
information can directly affect molecular mechanisms of the brain,” said
Paul Sanberg, director of the University of South Florida College of
Medicine's Center of Excellence for Aging and Brain Repair.

The research could indeed be used to help scientists find new drugs to
help the brain repair itself following damage, Sanberg said. However,
“there are still many more studies that need to be done to understand
plasticity in other parts of the brain and how to translate it to human
problems.”

More information

Learn more about brain plasticity from the University of Washington.