Contact: Holly Korschun
hkorsch(AT)emory.edu
404-727-3990
Sarah Goodwin
sgoodwi(AT)emory.edu
404-727-3366
Kathi Ovnic
covnic(AT)emory.edu
404-727-9371
Emory University Health Sciences Center
Emory Neuroscientists Use Computer Chip To Help
Speech-Impaired Patients Communicate
For patients left paralyzed and unable to speak from a spinal cord
injury or stroke, communication is a
constant challenge that threatens independence, emotional well
being and health.
Roy E. Bakay, M.D., a neurosurgeon at Emory University and
neuroscience colleague Phillip R.
Kennedy, M.D., have developed a neurotrophic electrode that can be
placed in the brain to help these
patients communicate through a computer. The electrodes have been
successfully implanted into the
brains of two patients at Emory University Hospital, one with
amyotrophic lateral sclerosis (ALS, or
Lou Gehrig's disease) and one with brainstem stroke.
Drs. Bakay and Kennedy present this research at the Society for
Neuroscience meeting in Los Angeles
this week.
"A person can interact with the world if they can use a computer,"
Dr. Bakay said. "This development
will open up a tremendous amount of opportunity for patients who
have lost the ability to move and talk
because of stroke, spinal cord injury or diseases like Lou Gehrig's
disease."
The neurotrophic electrode is implanted into the motor cortex of
the brain using a tiny glass encasing.
Neurotrophic factors are implanted into the glass, and the cortical
cells grow into the neurotrophic
electrode and form contacts. It takes several weeks for the
cortical tissue to grow into the electrode.
The neurons in the brain transmit an electronic signal when they
"fire." Recording wires are placed inside
the glass cone to pick up the neural signals from the ingrown brain
tissue and transmit then through the
skin to a receiver and amplifier outside of the scalp. The system
is powered by an induction coil placed
over the scalp. There are no wires going through the skin. Neural
signals are used to drive the computer
cursor in the same way a computer mouse is moved back and forth.
The recorded neural signals are
connected to the computer and are used as a substitute for the
mouse cursor.
"The trick is teaching the patient to control the strength and
pattern of the electric impulses being
produced in the brain," Dr. Bakay said. "After some training, they
are able to "will" a cursor to move
and then stop on a specific point on the computer screen. If you
can move the cursor, you can stop on
certain icons, send email, turn on or off a light and interact with
the environment.
"Our present patient, who is at the Atlanta Veterans Affairs
Medical Center, is paralyzed except for his
face due to brainstem stroke following a heart attack, is dependent
on a ventilator and cannot speak, yet
he is fully alert and intelligent," Dr. Bakay said. "This patient,
who was implanted five months ago with
the electrode, can move the cursor from icon to icon in a
horizontal direction. As each icon is
encountered, a phrase is spoken by the computer. The patient's
favorite is, "See you later. Nice talking
with you."
"Our work with this patient is very successful, and we will be
continuing with this research," Dr. Bakay
said. "Our hope is that soon we will be able to get to the point
that we can connect the neural signals to
a muscle stimulator in the patient's paralyzed limb and have them
move that limb using the same principle
that they use to move the cursor."
Results from implanting the electrode in the first patient were
published in the June 1998 issue of
NeuroReport. The patient was able to control computer signals in an
on/off manner for 76 days before
she died from her terminal ALS condition.
More than 700,000 Americans suffer from stroke each year and tens
of thousands more suffer spinal
cord injuries or from diseases like Lou Gehrig's that threaten
their ability to communicate. Stroke is
currently the leading cause of permanent adult disability in the
United States.
The neurotrophic electrode technology was developed and patented by
Dr. Kennedy while at the
Georgia Institute of Technology. Its testing and development in
animals over the past 12 years has been
a collaboration between Emory University and Georgia Tech. The
research has been supported by the
Emory/Georgia Tech Biomedical Research Consortium, the American
Paralysis Association and the
Department of Veterans Affairs. The National Institutes of Health
(NIH) has recently awarded funding
to continue the Phase I research in at least one more patient.