Evidence for language (in)dependent phonetic representation in the bilingual mind: A case of acquired apraxia of speech

Munarriz, A. 1 , Ezeizabarrena, M. 1 , Mennen, I. 2, 3 & Kuschmann, A. 4

1 University of the Basque Country-ELEBILAB
2 ESRC Centre for Research on Bilingualism
3 School of Linguistics and English Language, Bangor University
4 Speech and Language Therapy Division, Strathclyde University, Glasgow

Apraxia of Speech (AOS) is an acquired motor speech disorder that has been localized at the level of phonetic encoding in psycholinguistic speech production models. More specifically, it has been assumed that the speakers with AOS fail to activate the stored phonetic plans to produce frequent syllables, words and utterances. Several symptoms have been reported in the AOS literature which has been carried out mostly with monolingual patients: effortful speech, with articulatory groping and attempts at self-corrections, articulatory inconsistency on repeated productions of the same utterance, reduced coarticulation, dysprosody and/or difficulty initiating utterances (Dronkers, 1996; Aichert & Ziegler, 2004; Whiteside et al. 2010).
Previous research on spontaneous and elicited oral speech production of an early, highly proficient Spanish-Basque bilingual with Broca’s aphasia revealed that the linguistic impairment affected both languages similarly in qualitative terms, though quantitative differences were observed. In this talk, we present the phonetic results obtained from a reading task for which the following features were analysed: 1) Rate of articulation (number of syllables per second); 2) False beginnings, as a kind of articulatory groping; 3) Phonetic distortions; 4) The acoustic parameters to signal new and given information and the effect of position on the acoustic parameters. The results at phonetic level confirm the asymmetry between these two languages previously observed.
The present study provides new accurate data for a deeper understanding of the variables affecting the bilingual speaker’s performance at the phonetic level by testing the following hypothesis: a) the influence of syllable (Aichert & Ziegler, 2004) or rather word frequency (Varley & Whiteside, 2001) in the apraxic performance; and b) the existence of some language (in)dependent syllable representation in bilingual speakers (Alario et al. 2010).