Research into how the brain processes communication functions is
critical to helping stroke survivors recover lost language skills
About the Photo:
Research by Judy Walker, UMaine associate professor of communication
sciences and disorders, focuses on cognitive and linguistic
impairment following central nervous system damage.
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Bob Lundstrom had just finished
speaking on the phone with a lawyer and with the head of his company in
Sweden when a strange feeling came over him. It was as if his brain "was
Unaware of what was happening or of the severity of his condition, the
Georgetown, Maine, resident tried to continue his normal morning
routine. He stopped at the local post office, but left abruptly when he
was unable to communicate with the postmaster. Although Lundstrom was
unaware of it, his speech was incomprehensible, something of a "word
Lundstrom, a physicist and founder of his own wire-making company, then
drove to Bath to meet his wife for lunch driving, he recalls, "as
though I was drunk," the road appearing to him as though he was looking
backward through binoculars. By the time he arrived, it was clear
something was wrong, but Lundstrom could not articulate what he was
Such a sudden inability to communicate is one of the symptoms of stroke,
the nation's third leading cause of death. Those who survive strokes
often are unable to read, write or talk. Others like Lundstrom, who had
a stroke in 1996, may only be able to express part of their message,
without the appropriate or logical arrangement of words.
Their inability to process or produce language because of brain damage
is known as aphasia, which affects more than a million people in the
United States, according to the National Aphasia Association. People
with aphasia lose the ability to process and produce language in the
part of the brain that is damaged by stroke, says Judy Perkins Walker, a
University of Maine researcher and associate professor of communication
sciences and disorders.
Walker, who would eventually meet Lundstrom at a stroke survivors'
support group meeting, understands what happens when a stroke or brain
injury causes aphasia. She has spent 20 years working in hospitals with
patients who have brain damage and researching the complex effects of
such trauma. Patients who volunteer to cooperate with Walker in her
research are struggling to understand stroke damage and its effects.
Lundstrom agreed to participate in Walker's research and served as a
Walker's research is contributing to new understanding of how the brain
processes certain aspects of language. Her work blends scientific and
medical theory with research results and communication performance by
Walker is an internationally recognized authority on an area of
neurolinguistics concerning prosodic deficits in brain-damaged subjects,
and has published numerous articles in scientific journals on her
research. She speaks on the topic throughout Maine, nationally and
internationally. With response-time experiments and acoustic analyses of
speech production, Walker currently is focusing on how language is
processed and produced by people who have had strokes.
Specifically, Walker studies prosody, or the melody of speech that helps
us understand language through more than mere words. She concentrates on
injuries to the left hemisphere of the brain, the area that controls our
ability to understand and produce language, including intonation and
accenting on specific words or syllables to assist in recognizing nouns
Patients with right hemisphere damage also are part of Walker's
research. The right hemisphere is responsible for spatial and perceptual
functioning, including a person's ability to decipher emotion and
non-verbal communications that may be conveyed through prosody.
Walker's research expands on existing theory that explains how the left
and right hemispheres work together to process the overall meaning of
sentences. The left hemisphere processes prosody that conveys linguistic
meaning; the right hemisphere processes aspects of prosody that convey
To understand the linguistic distinctions that Walker asks her research
subjects to make, consider words like "suspect," "convict" or "permit"
that carry multiple meanings as nouns or verbs, depending on which
syllables are stressed. Aphasic subjects may hear the tonal distinction,
but may be unable to understand it when the message reaches the damaged
left hemisphere of the brain.
In a similar example, consider the parsing, or grammatical
interpretation of a sentence like, "The man who hunts, ducks out in
winter." Aphasic subjects may overlook the comma or not register the
pause, parsing the sentence incorrectly: "The man who hunts ducks, out
Linguistically, people tend to associate words that naturally go
together, like "hunts ducks," according to Walker. But prosodic cues can
direct a listener to parse the sentence differently.
Perhaps more troubling for an aphasic subject is the inability to
understand whether a question is being asked or statement being made by
the rise or drop in tone at the end of a sentence. They hear the change
in intonation, but they do not process what it means.
Conversely, a subject with right hemisphere damage may have trouble
distinguishing emotional meaning in a sentence that is conveyed through
In her work with people who have brain damage, Walker measures response
times and accuracy as they decipher words and sentences. With the latest
acoustic equipment in her laboratory, Walker also can measure the
features of prosody, such as increased syllable duration components of
speech that can be altered by stroke damage.
The complexity of language processing and production often is taken for
granted, Walker says, but it is important in determining what
communication functions have been compromised by the damage and what
therapy will be most effective in treatment. That's why she and other
researchers are trying to establish the degree to which prosody affects
understanding and production of meaningful sentences in people with
Using her findings, she hopes to help develop more effective therapies
so people with aphasia can recover communication skills or at least
compensate for them sooner.
Students in the Department of Communication Sciences and Disorders find
Walker's research and classes particularly insightful and memorable.
Research assistants under her supervision often work with aphasic
subjects. Recent UMaine graduate student Rebecca Pelletier, now a speech
pathologist working at a rehabilitation center and a hospital in Bangor,
studied under Walker in courses and as a research assistant. She says
Walker's anecdotal teaching methods introduce students to the realities
of patients' symptoms and struggles. They also learn about the
importance of family support in a stroke survivor's recovery, she says.
Before joining the University of Maine faculty in 1997, Walker spent
many years as a clinician and researcher working with patients with
neurological disorders in such settings as the Veteran's Administration
Hospital in Houston, Massachusetts General Hospital and Spaulding
Rehabilitation Hospital in Boston, and Dartmouth-Hitchcock Medical
"My focus is really to teach students to become future speech-language
clinicians who will work in medical settings, helping patients get back
on their feet and start living a life as normal as possible after a
Bob Lundstrom's stroke wiped out an entire vocabulary in English and
German languages, and his grasp of Morse code.
"It was a powerful thing for me in the hospital for a long time,"
Lundstrom says. "I couldn't (verbalize that) I wanted a glass of water.
You can't imagine the frustration a patient has. I couldn't read, write
or spell. I couldn't understand what they were saying on TV."
In the months of therapy designed to get him to use other parts of his
brain, Lundstrom began memorizing words again. He practiced them one by
one, with his speech therapist and his wife all part of the support
team Walker says is important for recovery.
"Someone's got to look you in the eye and say You can do it,'" says
Lundstrom, 67, who now speaks about his experiences in Walker's classes.
"It's going to be somebody like Dr. Walker or someone she's taught."
After his stroke, even Lundstrom's then 4-year-old grandson was part of
the therapy. He told his grandfather: "Papa, you taught me the names of
the trees. Now I'll teach them back to you."
by George Manlove
for more stories from this issue of UMaine Today Magazine.