Alberta Innovates- Health Solutions

Lori Buchanan was a psychology graduate student when her 32-year-old brother suffered a massive stroke that wiped out the part of his brain responsible for understanding and speaking language. All that doctors could tell shocked family members was that he had a language problem.

They couldn't say where the problem was, what he was capable of understanding or doing, or what could be done to help him communicate better. "My brother couldn't distinguish between a conversation and the noise of a vacuum cleaner, " Dr. Buchanan remembers. The lack of research and patient information was the key factor in her decision to pursue a career in neuropsychology: the area she chose to explore was brain-injury impairment of language.

Eight years later, Dr. Buchanan and her research team are taking their investigations to a new level of technical sophistication. With the help of powerful and precise images conveyed by a magnetic resonance imaging (MRI) machine, the team will be able to view blood flow stimulated by electrical activity in the brain when patients undergo simple language tests. Depending on what the scan shows, Dr. Buchanan hopes to determine which of several approaches to language are still functioning in the person's brain.

"Most of us, when we come across a word we don't know, have various strategies for approaching it. For example, we may sound it out and think about its roots. People who are brain-injured may be left with an exaggerated strategy or maybe stuck with just one strategy.

By comparing the patterns of activation revealed by the MRI of unimpaired people to those with language impairments, we hope to match a pattern of activation in the brain with a strategy."

Three main processes are involved in reading. The visual look of a word is called orthography, the way it sounds is phonology, and the way it is understood is called semantics. The processes are fairly independent of each other and can occur in different sequences, but most people use all three. Dr. Buchanan and her team, post-doctoral fellows Dr. Ana Adelstein and Dr. Chris Westbury, are developing ten variables, based on such features as frequency of a word or sound, for each of the three processes. A patient's reaction time to words are compared to the variables and analyzed by a mathematical process, called structural equation modelling. The results indicate which processes work or don't work in the brain-injured patient. Dr. Buchanan hopes that once strategies that work or could work for patients are identified, therapies could be developed to help recover or strengthen language ability.

She comments, "The things we don't know about language and the brain are exactly the same as they were 100 years ago, which is terrible but exciting too because of the possibilities for research that will ultimately help the brain-injured."

Dr. Lori Buchanan is a Heritage Scholar in the U of A's Psychology Department.

Resources for brain-injured people:

Provincial resource for agencies and organizations:
Brain Injury Association of Alberta
Toll-free 1 800 533-5355
(Calgary) (403) 207-5606

Edmonton: The Northern Alberta Brain Injury Society
(780) 479-1757

Calgary: The Southern Alberta Brain Injury Society
(403) 521-5212

Relevant Website:
Vancouver Island Head Injury Society:
http://www.bc1.com/vihis/links.htm