A Case Study of a Multilingual Individual with Primary Progressive Aphasia: Diagnostic Considerations and Implications for Language Representation.

Abstract

Objective: This study reports a case of primary progressive aphasia (PPA) in a multilingual Haitian American individual. Earlier literature has suggested that cases of PPA in multilingual individuals are relatively rare. Several factors complicate the assessment of language dysfunction and diagnosis of PPA in multilingualism, including age of language acquisition, degree of proficiency, language representation in the bilingual brain, and limited availability/validity of tests/norms for bilinguals.

Method: This is a 69-year-old right-handed trilingual (French/English/Haitian Creole) Haitian American female with 16 years of education. Difficulties with word finding and speech production emerged two years prior to evaluation. Language was assessed with select subtests of the Boston Diagnostic Aphasia Examination (BDAE-3), Boston Naming Test (BNT), and Verbal Fluency. Positron emission tomography-computed tomography imaging displayed large areas of hypometabolism in the left and right frontal, temporal, and parietal lobes, with the left areas being more greatly impacted.

Results: Neuropsychological testing showed impairments in visual and auditory naming, verbal fluencies, sentence repetition, and word reading. Reading comprehension and repetition of single words were relatively spared. There were deficits in learning/memory, visuospatial functioning, and processing speed. Speech was dysfluent with occasional agrammatism and mild dysarthria.

Conclusions: Overlapping characteristics of both logopenic and non-fluent/agrammatic variants of PPA were evident. Patient's neuroimaging findings and clinical presentation suggest an advanced PPA syndrome. Cognitive/brain reserve and a globalized language representation, theorized in bilingual individuals, could be considered as contributors to the trajectory of her deficits. This case study contributes to the growing literature on PPA in diverse populations and multilingual individuals.