Neuroscience can foster better approaches to aphasia treatment
“This is a clinic; this is not a research study. But we have designed the clinic as though it were an experiment.”
Robert Fucetola, PhD
Bill Edmunds suffered a stroke in 1998. He is grateful that his body was not paralyzed, but it did have a paralyzing effect on the regions of his brain involved in language.
Edmunds was diagnosed with Wernicke’s aphasia, a condition that left him unable to speak intelligibly or understand what others were saying.
“It was awful,” he recalls. “The thoughts and ideas were still there, but they were always locked inside my mind.”
Edmunds was one of the first patients treated at an innovative new clinic that merges research and clinical care at Washington University Medical Center. This integrated approach helped him relearn how to talk, write, read and understand the spoken word.
Like any other rehabilitation clinic, the aphasia clinic’s primary goal is improving patient quality of life. But the clinic’s founders have another important item on their agenda: to put science firmly in charge.
“Many concepts currently being used in rehab clinics are treatments that have not been evaluated in rigorous evidence-based trials or are not based on current neurobiological understanding,” says Maurizio Corbetta, MD, the Norman J. Stupp Professor of Neurology and clinical director of the Rehabilitation Institute’s Stroke and Brain Injury Program.
Together with Robert Fucetola, PhD, assistant professor of neurology, Corbetta set out to revamp existing aphasia treatment programs. They devised a number of reforms and new approaches that apply scientific principles to ensure that patients receive the most effective therapies available and to mandate continuing reevaluation of the treatments’ effectiveness.
“You might be thinking, ‘Well, isn’t that what any other medical specialist would do?’” Fucetola says. “But actually, that’s not what typically happens in rehab, and we wanted to change that.”
Corbetta thinks most rehabilitation clinics have not taken advantage of a series of dramatic advances in neuroscience. Many of those changes center on scientists’ sense for how much the mature brain can change and adapt to injury.
“For many years, we thought that the adult brain had no plasticity, which is the ability to either form new connections or for still-healthy brain regions to adapt themselves to take on the functions of brain regions lost to injury,” Corbetta says. “But there has been more and more evidence that the adult brain
Growing awareness of the brain’s remarkable ability to recover lost function has been pleasantly surprising, but it also has posed a complex question: How much of the restoration that patients experience in rehab has been due to the treatments they receive, and how much of it stems from the brain’s own natural recuperative abilities? Corbetta and Fucetola hope the design of the new aphasia clinic can help them draw that distinction more clearly.
At the start of their redesign efforts, Corbetta and Fucetola spent nearly two years conducting an extensive review of the last 40 years of published scientific literature on speech therapy treatments.
“It was an ocean of treatment trials, but the quality was variable,” Corbetta says. “We evaluated how scientifically rigorous the evidence presented by each paper was and assigned them to a category based on that evaluation.”
At the same time, they developed a process for detailed testing and categorization of the disabilities aphasia inflicts on a patient’s language skills. Patients may have one or more of many types of language problems linked to aphasia. Each of these problems needs different treatment, Fucetola notes, but in many current rehab clinics the patients’ problems are never given a particularized assessment.
The new Evidence-Based Aphasia (EBA) clinic is different. The disability categorization system (based on an up-to-date model of language function including linguistic, neuropsychological and brain imaging information) and the literature review of speech therapy treatments came together in a series of clinical decision-making flow charts that match components of disability and neuroanatomical information with treatments deemed most likely to be helpful.
For many patients, treatment means long hours spent in simple language exercises, such as repeating a word or rhyming short words — grueling work that sometime lasts five to six hours a day, five days a week. Such intense practice has been shown to be most effective at helping patients regain skills.
For Bill Edmunds, the process has been very beneficial: He has recovered to the point at which he now works as a volunteer at Barnes-Jewish Hospital and has started sending out his resume to potential employers.
“I’m nervous about what could happen, but you have to keep moving,” he says. “You’ve lost if you stop.”
Patients enrolled in the EBA clinic also can participate in research programs on brain recovery funded by the National Institutes of Health and the J.S. McDonnell Foundation. Corbetta and Lisa T. Connor, PhD, research instructor in radiology, are using functional brain imaging scans to understand the neural mechanisms underlying language recovery in patients with aphasia. They also are trying to develop predictors of good vs. poor outcome.
“We’ve discovered that patients with reactivation on the left side around the areas damaged by stroke tend to recover better than patients in whom the right side of the brain becomes more active after stroke,” Corbetta says. Now Connor is beginning to test the brain changes induced by new speech therapy interventions.
As a patient progresses through treatment in the EBA clinic, he or she is evaluated every six months by a clinician unfamiliar with the patient’s history: how long ago the stroke occurred, location of the lesion, method of treatment, the detailed nature of their disability. All the evaluator knows is that the patient has aphasia. The goal is to keep a separation between clinicians measuring the impairment or disability and those treating the patients. This “double blind” principle, essential in other specialties but less common in rehabilitation, prevents an evaluator who also is providing treatment from delivering a biased assessment of the treatment’s results. The method, says Corbetta, is critical to confidently assess the efficacy and validity of an intervention.
“This is a clinic; this is not a research study,” notes Fucetola. “But we have designed the clinic as though it were an experiment.”
Patient progress also is assessed through other sources, including interviews with family members and friends and tests of the patient’s ability to use language in real-life contexts.
If a treatment seems to be having little effect, a record is made and another treatment is tried. Over time, these records help clinicians more effectively match patients to the treatments most likely to be beneficial.
The researchers plan to share what they are learning with other clinics via publications and presentations at scientific meetings. A 2005 paper published in the journal Aphasiology reports the first results obtained in the new clinic.
Corbetta and his colleagues have already begun laying the groundwork needed to apply this model of clinic design to other disabilities induced by stroke and traumatic brain injury.
“Stroke is the third-leading cause of death, but it is the number one cause of disability,” Corbetta notes. “And there’s a real need to scientifically prove that our interventions for patients can significantly help them overcome those disabilities. We need that both in terms of justifying the economic costs of treatment to policy makers and in our efforts to actively develop and improve therapy.”