Quantifying three types of abnormal language in semantic variant primary progressive aphasia

Abstract

AbstractBackgroundPatients with the semantic variant of Primary Progressive Aphasia (svPPA) experience a gradual loss of semantic memory, impairing word retrieval and word comprehension. As such, svPPA patients often use superordinate, vague, and empty words. These patients often use language that refers to one’s own experience (“self‐referential”), one’s language impairments (“inability”), and/or contains tangents (“tangential”). These forms of aberrant language were identified previously as distinguishing svPPA from the other canonical variants of PPA (Gallee et al., 2021).MethodSpeech samples of the WAB picnic scene from 15 svPPA patients were analyzed by counting words and categorizing three forms of aberrant language at two timepoints (30 samples total), baseline and follow‐up (at least 12 months post baseline). Words were identified as self‐referential, inability, or tangential. Quantitative analyses were conducted to look for relationships between total word count and each of the three forms of aberrant language.ResultPreliminary results showed a strong correlation (r = .97) between the total number of aberrant words and the total number of words in the picture description transcriptions. At T1, 40% (6/15) used self‐referential words, 87% (13/15) used inability words, and 53% (8/15) used tangential words. At T2, 67% (10/15) used self‐referential words, 100% (15/15) used inability words, and 67% (10/15) used tangential words. Inability is the most prominent type of aberrant language. Longitudinal analyses are ongoing to investigate consistency or inconsistency within patients and relationship to aphasia severity.ConclusionPreliminary findings suggest patients with svPPA produce distinct types of aberrant language in a picture description task. The prominent use of inability words may be due to its scripted nature in that svPPA patients use these phrases repeatedly and may be related to disinhibition. Further, it is notable that several components of language not analyzed in this study, including grammar, syntax, and content units, are potentially informative. Using this method provides an efficient way to characterize speech of svPPA patients, which may lead to early subtyping, prognostication, and targeted treatment goals.Reference: Gallée,J.;Cordella,C.; Fedorenko, E.; Hochberg, D.; Touroutoglou, A.; Quimby, M.; Dickerson, B.C. Breakdowns in Informativeness of Naturalistic Speech Production in Primary Progressive Aphasia. Brain Sci. 2021,11, 130.