Yunjung Kim, communication sciences and disorders assistant professor, will spend the next three years studying the relationship between speech disorders and Parkinson’s disease.

Kim received a $426,999 grant earlier this month from the National Institute on Deafness and Other Communication Disorders to conduct cross-linguistic studies comparing Parkinson’s disease patients who are native English speakers to those who natively speak Korean. 

Kim said in the past, researchers ignored dialects and language variations in these types of studies, but language variations may actually affect speech disorder diagnostics.

She said special software helps her determine if someone has a speech disorder by displaying residual frequencies to allow her to see the acoustic signals, or indications of how the tongue moves.

As for speech disorders in Parkinson’s disease, Kim said she will study the relationship between the disorder and speech. But she wants to find out if the speech disorder is language-universal, caused by the nature of the disease, or language-specific, resulting from the type of language or the way it is spoken.

Kim said if she can determine how much of the disease is language-universal and language-specific, she can more easily understand how the disorder works and how it affects language.

Kim said Parkinson’s disease patients have a more difficult time pronouncing vowels. The English language contains more vowels than Korean, so native English speakers may have more trouble with their language, she added. 

Kim said the idea that listeners do not think someone’s speech is intelligible enough to be considered normal interests her. 

Melda Kunduk, associate professor of communication sciences and disorders, said someone may have a speech or voice disorder if he or she cannot be easily understood, does not have clear speech or has an unusual-sounding voice, like those with rough or hoarse voices. 

“If their speech or voice is distracting, then you have to find why it is so distracting,” Kunduk said.

Kim said she and a few University graduate students will use native English-speaking Parkinson’s disease patients from Baton Rouge and will travel to Seoul, South Korea, at least once a year to research native-speaking patients there.