Frontiers in Psychology (Apr 2014)
Speech deterioration in an English-Shanghainese Speaker with Logopenic Variant Primary Progressive Aphasia
Abstract
Background and Purpose There are three forms of Primary Progressive Aphasia: nonfluent/agrammatic, semantic, and Logopenic (PPA-LV). Differential diagnosis of PPA requires multiple sources of information including assessment of connected speech. Simply extending connected speech analysis measures developed for vascular aphasia obscures essential features of PPA-LV. The LCM-SS (Hilger et al., in press) was, therefore, designed to capture semantic, morpho-syntactic, and phonemic characteristics of PPA-LV. In this study we compare deterioration of English and Shanghai Chinese (Shanghainese) over two years in a bilingual woman (BYR) with PPA-LV. Participant BYR was born and raised in China speaking Shanghainese. She was educated in English and attended college in Ireland. She then lived in English-speaking countries and was married for 40 years to a monolingual English-speaking partner. She began experiencing word finding difficulty at age 70, was diagnosed with PPA at 72, and began providing longitudinal data for our research team at age 76. BYR’s initial symptoms in both languages, as assessed by the Boston Diagnostic Aphasia Examination, were largely consistent: word-finding difficulties, false starts, and occasional omission of grammatical morphemes, but fairly rich syntax. Procedures Seven Cookie Theft picture narratives, gathered in both languages over the course of 27 months, were analyzed using the LCM-SS. Results LCM-SS counts and indices were plotted to reflect change over time and individual trend lines were created. Data for each measure were correlated with corresponding trend lines; those with R-values of 0.50 or greater were considered indicative of reliable trends. Slopes were used to determine the direction of change, if any (Table 1). Discussion The overall pattern of preservation and deterioration was generally consistent across both languages. Some differences in index changes were related to language-specific difference between English and Shanghainese. A post-hoc analysis of the morphosyntactic errors indicated that apart from the misuse/missing of functors in both languages, an additional source of Shanghainese errors was morpheme omission in Chinese compounds. (Note that the morphosyntactic errors in both languages did not differ across time in terms of absolute numbers). The fact that BYR used Shanghainese much less than English for many years could explain some of the greater difficulty she experienced with word finding related measures (such as increased values on Index of Lexical Efficiency and decreased total content units) as compared to English. Other differences are explained by the fact that Shanghainese words generally consist of one or two morphemes; each morpheme is a monosyllable with very simple structure. The decline in the Index of Grammatical Support in Shanghainese, but not in English can thus be explained by considering that word-onset difficulties in Shanghainese manifested as repetition of the entire initial syllable (morpheme), while in English, they took the form of phonological repetition, i.e. multiple false starts. This reminds us that the structure of a language at all levels must be considered when classifying and comparing errors across languages.
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