A new study suggests that dementia-related language symptoms may differ in persons diagnosed with primary progressive aphasia (PPA) based on the features of their native language, according to researchers at the UC San Francisco (UCSF) Memory and Aging Center.

The study, published January 10 in Neurology, focused on English and Italian speakers diagnosed with the nonfluent variant of PPA. Persons with this PPA variant have increasing difficulty pronouncing words and using correct grammar, but generally retain their ability to understand spoken language.

While cognitive tests and brain scans showed similarities in levels of functioning and brain degeneration between English and Italian speakers, comparisons of linguistic tests revealed key differences in speech and reading difficulties.

Researchers believe the differences are linked to features of the participants’ native languages, questioning a long-standing assumption that speech-disrupting brain diseases manifest similarly in people around the world. The findings will help to advance efforts to ensure accurate diagnoses for persons with PPA across different cultures.

“Clinical criteria for diagnosing disorders that affect behavior and language are still mainly based on studies of English speakers and Western cultures, which could lead to misdiagnosis if people who speak different languages or come from another cultural background express symptoms differently,” said study senior author Dr. Maria Luisa Gorno-Tempini (pictured above), of UCSF Memory and Aging Center, in a news release.

Future studies will attempt to replicate the findings on a larger scale to identify further differences between speakers of English and more diverse, non-Western languages.