This article highlights
national and international developments in aphasia therapy
research over the past two years. We will focus on three
areas: 1 ) the emergence of nontraditional treatments
for aphasia, 2) the need to place aphasia treatment
within the context of the complex brain mechanisms involved
in the recovery process as well as the need for clinicians
to apply theoretical frameworks in deciding the course
of patient treatment, and 3) developments in the frontiers
of neuroscience.
1) NON TRADITIONAL MODES OF APHASIA
TREATMENT
Many researchers are studying nontraditional techniques
for aphasia treatment, that is, approaches that supplement
speech therapy. Pharmacological approaches to aphasia
continue to generate excitement. In one study by Tanaka
and colleagues in Japan and Boston, mildly to moderately
impaired fluent aphasic subjects showed improvements
in naming ability when using cholinergic (neurotransmitter)
therapy. This therapy involves using drugs to improve
the functioning of the damaged brain.
Two other studies used a different
neurotransmitter, bromocriptine (a dopaminergic agent)
to improve verbal output in chronic nonfluent aphasic
subjects. Bragoni and colleagues at the University of
Roma La Sapienza, in Italy studied the combined effects
of bromocriptine and speech therapy. Their results indicated
that high dosages of bromocriptine improved performance
in a number of language skills. Gold and colleagues
at the University of South Florida also found that bromocriptine
improved the verbal performance of their subject.
Research on the use of amphetamines
to treat aphasia is part of an on-going series of studies
by Walker-Batson and her colleagues in Dallas. In their
most recent study, which was reported this fall, they
found amphetamines paired with regular speech/language
therapy facilitated language recovery in the period
shortly after stroke.
The drug, piracetam, has been tested
on patients with aphasia in several clinical research
trials in Germany. A recent report by Kessler and colleagues
suggests that it may be another drug that holds promise
for treatment of aphasia. In sum, results from studies
using pharmacologic interventions for the treatment
of aphasia have been encouraging.
Researchers are also looking at other
types of nontraditional treatments. For example, Pulvermuller
and colleagues used "Constraint-Induced (CI) Therapy"
to treat language disorders in subjects with chronic
aphasia. This approach was used originally in subjects
who had paralysis of an arm or leg following a stroke,
and consists of intensive, concentrated use of the weakened
arm or leg, while preventing the use of the healthy
limb. In patients with aphasia, the same principle applies:
CI therapy requires that a patient participate in intensive
practice of one means of expression (for example, speaking
out loud) while restricting the use of alternative methods
(for example, gesturing). Using this technique, the
authors found significant improvements in the ability
of a small group of patients with chronic aphasia to
verbalize in a relatively short period of time.
In response to studies reporting that
psychological factors may influence recovery, Laura
Murray and her colleagues used relaxation therapy in
conjunction with traditional aphasia therapy to improve
verbal performance in chronic nonfluent aphasic subjects.
In their study, relaxation training included both guided
imagery and progressive muscle relaxation. Their one
subject with chronic nonfluent aphasia showed improvement
in spoken language with this technique.
2) MAKING TREATMENT DECISIONS
Murray's approach illustrates the point that many factors
may influence the recovery of language following a stroke.
Neurological, behavioral, cognitive, linguistic, and
psychosocial aspects of the recovery process have been
studied for decades. Among researchers, the term for
considering these various components together is "using
a multifactorial model." This phrase means that
there are multiple factors at work in a given process,
such as recovery. Chris Code attempted to analyze further
some of the factors and noted the need to consider the
connections among them. For example, emotional and psychological
factors may influence the ability to regain language
at early stages of language recovery. Perhaps further
research will document that it is the interactions among
these levels that will most influence decisions regarding
appropriate treatment approaches.
Other treatment studies during the
past two years continue to emphasize the need for clinicians
to apply theoretical frameworks in their practice. A
theory-driven approach helps the clinician decide which
techniques to use and to give a context for determining
whether they are working.
Basso and her colleagues stated that
speech-language pathologists are aware of the need for
theory-based treatment and that a comprehensive evaluation
will assist them in either determining the most appropriate
treatment approach or eliminating an inappropriate treatment
approach.
One example of the use of theory to
guide treatment decisions comes from Laura Murray in
her 1999 article on attention and aphasia. The author
introduced attention theory, reviewed the literature
on attentional impairments in aphasic adults, and described
ways in which knowledge of attention theory may influence
the evaluation and treatment of language production
and comprehension in adults with aphasia. If an individual
has difficulty with attention, that fact may negatively
affect any type of speech and language therapy.
Another example is from Jacqueline
Hinckley and her colleagues, who used theoretical frameworks
to apply and compare two different approaches to the
treatment of aphasia. These researchers compared two
widely used techniques: "context based" treatment
in which communication skills are targeted and practiced
within a specific context or setting (for example, a
casual conversation) and "skill based" treatment
in which component skills of a task are practiced (for
example, the specific tasks needed to improve oral reading).
The findings, although from a small group of subjects,
indicated that skill based treatment has a broader impact
on the individual's use of language than context based
treatment. Other researchers with recent papers on this
topic include Alison Ferguson at the University of Newcastle,
NSW Australia and Wendy Best at Birkbeck College and
the University of London, UK.
3) FUTURE TRENDS
Advances in research on neural regeneration and the
use of biotechnology will also influence the future
of aphasia therapy. Results from laboratories studying
neural regeneration, such as one at the Harvard Medical
School/McLean Hospital in Belmont, Massachusetts, are
promising (Isacson 0. et al, 2001). They have been using
cell implantation into living brain to facilitate recovery
from brain damage. Their studies indicate that cell
transplantation, which promotes the restoration of brain
tissue after brain injury, may benefit patients with
Parkinson's disease. The field of brain cell transplantation
is still in its infancy and is fraught with controversy,
but represents a trend to watch over the next few years.
In the field of biotechnology, Repetitive
Transcranial Magnetic Stimulation has been used on a
small group of patients with nonfluent aphasia to improve
naming skills. Margaret Naeser from the Harold Goodglass
Aphasia Research Center at Boston University School
of Medicine and the VA Boston Healthcare System, and
Alvaro PascualLeone from Boston's Beth Israel Deaconess
Medical Center and Harvard Medical School used magnetic
stimulation to influence brain function in various regions
of the brain cortex, and then measured the effects of
this procedure on naming skills. Results thus far, though
on a small group of subjects, and highly experimental,
have demonstrated improvement in naming in patients
with non-fluent aphasia.
With respect to all of the patient
studies described above, it is important to note that
they were done with small numbers of participants. Before
any broad conclusions can be drawn about the efficacy
of these experimental treatments, researchers will need
to complete additional studies with larger subject groups.
We continue to hope that research of this type will
yield successful therapy techniques for individuals
with aphasia.
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