When Dementia Harms Speech, Native Language Matters
WEDNESDAY, Jan. 22, 2020 (HealthDay News) -- Dementia patients may develop distinct speech and reading problems depending on their native language, a new study finds.
The study included 20 English-speaking and 18 Italian-speaking patients with primary progressive aphasia (PPA), a neurodegenerative disorder that affects language areas in the brain. It is often associated with dementia.
The patients had a type of PPA characterized by difficulty producing or pronouncing words (nonfluent PPA).
While both groups of patients had similar levels of degeneration and brain function, English-speakers had more trouble pronouncing words -- a traditional sign of nonfluent PPA -- and tended to speak less than usual.
The Italian-speakers had fewer pronunciation difficulties but tended to produce much shorter and grammatically simpler sentences, according to the study published recently in the journal Neurology.
"We think this is specifically because the consonant clusters that are so common in English pose a challenge for a degenerating speech-planning system," said senior author Dr. Maria Luisa Gorno-Tempini. She's a professor at the University of California, San Francisco's Memory and Aging Center.
"In contrast, Italian is easier to pronounce, but has much more complex grammar, and this is how Italian-speakers with PPA tend to run into trouble," she explained in a university news release.
The findings could improve accurate diagnosis of PPA in patients across different cultures, according to the researchers.
Gorno-Tempini noted that clinical criteria for diagnosing disorders that affect behavior and language are based mainly on studies of English-speakers and Western cultures, which could lead to misdiagnosis.
"It is critical going forward that studies take language and cultural differences into account when studying brain disorders that affect higher cognitive [mental] functions -- which we know are greatly impacted by culture, environment, and experience," she concluded.
The National Aphasia Association has more on primary progressive aphasia.