Priming the Brain to Recover from Stroke

Asst. Prof. Lara Boyd’s research is already showing promising results - photo by Martin Dee
Asst. Prof. Lara Boyd’s research is already showing promising
results – photo by Martin Dee

UBC Reports | Vol. 55 | No. 2 | Feb.
5, 2009

By Catherine Loiacono

For the 300,000 Canadians living with the aftermath of a
stroke, partial paralysis and loss of independence is a daily

Now a UBC brain stimulation technique that primes the brain
to relearn and retain old movements is showing encouraging
results for faster and more effective recovery. A wand, connected
to a computer, is placed adjacent to persons head and a stimulus
is applied.

“Currently, there are no drugs to help stroke patients
regain mobility,” says Lara Boyd, UBC assistant professor
of Physical Therapy in UBC’s Faculty of Medicine. “Thus
far, physical therapy has proven to be an effective treatment
for stroke patients to regain mobility. However, one of the
biggest challenges is the time and amount of practice it
takes for the brain to relearn an old movement.”

The two-part study tests a healthy brain first to ensure
the technique is safe and that there are no adverse effects
and then applies the same technique to a stroke-affected
brain. The study is currently in the second phase.

Following a stroke, the affected part of the brain is no
longer active because of the loss of blood flow, which causes
brain cell death. The area of the brain affected by the injury
determines the patient’s inability to move, see, remember,
speak, reason and read and/or write.

“One of the reasons that it is so difficult for the
brain to recover from a stroke and reorganize itself is that
the side of the brain that is damaged becomes suppressed
while the undamaged side becomes hyperactive,” says
Boyd, who is a Canada Research Chair in Neurobiology of Motor
Learning. “The left and right side of the brain become
unbalanced. It becomes more difficult for the affected side
of the body to move because the damaged side of the brain
is suppressed. Conversely, the unaffected side of the body
moves much easier because the undamaged side of the brain
becomes hyperactive.”

This negative feedback loop helps explain why it becomes
increasingly difficult for stroke patients to regain mobility.

“Fortunately, the brain is an amazingly dynamic organ
that can reorganize itself,” says Boyd, whose current
study looks at the benefits of applying an electromagnetic
stimulus to the stroke affected section of the brain. “What
we want to do is to stimulate and enhance brain cell reorganization
around the damaged part of the brain.”

In doing so, Boyd believes that the brain can reorganize
itself and find an alternate pathway to performing a previous

The first part of the study tested individuals who had never
suffered a stroke. The participants received an electromagnetic
stimulus and were then asked to practice a specific movement.
Participants who received the stimulus demonstrated increased
and improved learning for 15 – 20 minutes following the stimulus.

“Preliminary results of our research on non-stroke
patients show that if you pre-excite the brain by applying
an electromagnetic stimulus, motor learning and retention
of skill is improved and retained,” says Boyd. “We
are currently applying this technique to the stroke affected
brain and the available data is positive. We are quite optimistic
that this approach will work and we expect results in the
coming months.”

According to the Heart and Stroke Foundation, each year, there
are between 40,000 to 50,000 strokes in Canada and close to
16,000 Canadians die.