Canadian scientists in Toronto have found astonishing evidence that the lifelong use of two languages can help delay the onset of dementia symptoms by four years compared to people who are monolingual.
There has been much interest and growing scientific literature examining how lifestyle factors such as physical activity, education and social engagement may help build "cognitive reserve" in later years of life. Cognitive reserve refers to enhanced neural plasticity, compensatory use of alternative brain regions, and enriched brain vasculature, all of which are thought to provide a general protective function against the onset of dementia symptoms.
Now scientists with the Rotman Research Institute at the Baycrest Research Centre for Aging and the Brain have found the first evidence that another lifestyle factor, bilingualism, may help delay dementia symptoms. The study is published in the February 2007 issue of Neuropsychologia (Vol.45, No.2).
"We are pretty dazzled by the results," says principal investigator Ellen Bialystok, Ph.D., whose research team at Baycrest included psychologist Dr. Fergus Craik, a world authority on age-related changes in memory processes, and neurologist Dr. Morris Freedman, an eminent authority on understanding the mechanisms underlying cognitive impairment due to diseases such as Alzheimer's.
"Our study found that speaking two languages throughout one's life appears to be associated with a delay in the onset of symptoms of dementia by four years compared to those who speak one language," says Dr. Bialystok, Professor of Psychology at York University and Associate Scientist at the Rotman Research Institute at Baycrest.
The study follows on the heels of previous published reports by Dr. Bialystok and colleagues showing that bilingualism enhances attention and cognitive control in both children and older adults. Those results inspired Bialystok and her research team to ask, "So what does this mean for the onset of dementia?"
In this present study, researchers set out to answer that question by examining the diagnostic records of 184 patients who came to Baycrest's Sam and Ida Ross Memory Clinic between 2002 and 2005 with cognitive complaints. Of that group, 91 were monolingual and 93 were bilingual. The bilinguals included speakers of 25 different languages, the most prevalent being Polish, Yiddish, German, Romanian and Hungarian.
Researchers found that 132 patients met criteria for probable Alzheimer's; the remaining 52 were diagnosed with other dementias. Patient data included Mini-Mental State Examination (MMSE) scores (a measure of general cognitive functioning), years of education and occupation. The MMSE scores were equivalent for the monolingual and bilingual groups at their initial visit to the clinic, indicating comparable levels of impairment. The age of onset of cognitive impairment was determined by the interviewing neurologist at the first clinic visit who asked patients and their families or caregivers when symptoms were first noticed.
The researchers determined that the mean age of onset of dementia symptoms in the monolingual group was 71.4 years, while the bilingual group was 75.5 years. This difference remained even after considering the possible effect of cultural differences, immigration, formal education, employment and even gender as influencers in the results.
"There are no pharmacological interventions that are this dramatic," says Dr. Freedman, who is Head of the Division of Neurology, and Director of the Memory Clinic at Baycrest, referring to the four-year delay in onset of symptoms for bilingual patients.
"The data show a huge protective effect," adds co-investigator Dr. Craik, who cautioned that this is still a preliminary finding but nonetheless in line with a number of other recent findings about lifestyle effects on dementia.
The team is working on a follow-up study that will further examine bilingualism and dementia onset. They plan to conduct interviews and cognitive assessments on bilingual and monolingual patients in Baycrest's Memory Clinic and follow them for a few years.
© 2005-2007
Expert, Consultant and Keynote Speaker on Emerging Smart Technologies, Innovation, Strategic Foresight, Business Development, Lateral Creative Thinking and author of an upcoming book on the Smart Economy "
The Smart Technology Blog: The Smart Economy -- Read, enjoy, explore, speculate, comment !!
To arrange for an in house presentation or briefing on smart technology see here
To explore the opportunities and threats of any new smart technology in your industry - Contact Me or explore how we can work together
.....Strategy without action is a day-dream; action without strategy is a nightmare"- old Japanese proverb
".......Ours is the age that is proud of machines that think and suspicious of men who try to." - H. Mumford Jones
"Without changing our patterns of thought, we will not be able to solve the problems we created with our current pattern of thought." A. Einstein
"Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has." - Margaret Mead
P. S. if this is your first visit to my blog, please go to our Welcome page
Mr Derzko,
Just a remark: As speaker of 4 languages (Portuguese, German, Italian and English) and studying in a foreign country (Germany), I must say those that SURVIVE learning other languages (mainly German) should have at least 8 years handicap ;)
Jokes aside, I would like to take this opportunity thank you for the beautiful work. I regularly read and enjoy your blog and just noticed I never told you that ;)
Happy 2007,
Edu
Technology and Innovation Management MSc. Student
Posted by: Edu | January 12, 2007 at 11:52 AM