Spanish Learning Centre Blackpool

Bilingualism Delays Onset Of Dementia
Canadian scientists 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.

Earl Evleth
http://britishexpats.com/forum/showthread.php?t=418733