Phonological Processing of Second Language Phonemes

"Phonological processing of second language phonemes: A selective deficit in a bilingual aphasic."

Eviatar, Z., Leikin, M., & Ibrahim, R.

Presented by: Alejandro Lopez-Ambriz

The research detailed a case study on a bilingual Russian-Hebrew speaker, R.K, recovering from bilingual aphasia. The patient did not have problems with semantic processing after suffering a stroke, but did have issues processing words in Hebrew unless they were spoken with a Russian accent. This is to say that the patient could more efficiently make sense of words composed of Russian phonemes rather than Hebrew specific sounds. Noticing the disparity between rate of recovery in the two languages and the crossover effect between languages, researchers investigated what implications this held for models of phonemic processing and speech perception for acquired language bilinguals, specifically whether the faculties associated with processing the primary language are used to supplement processing of the second language. There is notably little previous work concerning phonological processing, the authors of this article noting that most contemporaries focused instead on production of second language phonemes and how production skills in bilinguals commonly outstrip their perception of those same sounds (e.g.,Caramazza, Yeni-Komshian, Zurif, & Carbone, 1973; Mark, 1989; Sheldon & Strange, 1982). From the trends in semantic understanding, lexical retrieval, and phonemic recognition, researchers hypothesized that the stroke damaged a lexical retrieval mechanism and that this mechanism was responsible for retrieval from both Russian and Hebrew. This falls in line with Hybrid Model of lexical representations (de Bot, 1992; de Groot, 1992), which also explains the preference for Russian over Hebrew, since this system would facilitate recall for terms that were acquired earlier, more frequently used, and more recently used (Snodgrass & Tsivkin, 1995).

The case study originally consisted of traditional recovery procedures associated with stroke-induced aphasia. These tests included the Boston Naming Test (BNT; Kaplan, Goodglass, & Weintraub, 1983), Western Aphasia Battery (WAB; Kertesz, 1982), and other tests intended to distinguish between semantic and lexical shortcomings. The BNT was used to determine R.K's ability to associate the appropriate word with an image, with initial results showing successful lexical retrieval for one in sixty trials in Russian and zero in sixty for Hebrew. The WAB showed visual ability and recognition consistent with an unafflicted individual of R.K's age (Spreen & Strauss, 1991). This test was also supplemented with a trial where experimenters asked R.K to assign images to categories, and another where R.K was asked to differentiate between the size or cost of two objects. In all cases R.K could successfully identify and appropriately differentiate between objects. The two additional trials, the one concerning size or cost differentiation especially, also aided researchers in ruling out conceptual memory as a confounding factor in their case study. When tested on their ability to identify the components of words (here meaning number of letters, the letters themselves, and number of syllables in a word), results varied by word length, with R.K showing improved performance with three to five letter words. It is worth noting though that the subject used colloquial phonetic sounds from their first language in place of formal letters when asked to spell out a word, and would use the phonemes from Russian to count syllables regardless of if the word was Russian or Hebrew. Lastly, R.K's reading and writing skills were scrutinized by researchers who asked R.K to read written words aloud and to write from dictation.

After compiling data and theorizing about the implications for models of speech perception and the operation of cognitive mechanisms in the subject's brain, the researchers stated that their data supported the Hybrid Model of lexical representations the most (de Bot, 1992; de Groot, 1992). This theory states that there is a single mechanism responsible for retrieval of semantic information in any given language. Lexical information is still archived separately, but they are not activated separately from one another. The specifics of R.K's anomia also suggest that there are switching mechanisms responsible for alternating between semantic and lexical databases, and between phonetic/phonemic stores. The former is speculated to be operated deliberately, while the latter is an automated process that, in R.K's case, was less well preserved after the stroke. The cognitive processes for phonemes is further divided into one of two proposed mechanisms, one of which suggests that all phonological processing passed through a Russian-based filter before being differentiated semantically into one language or the other. Alternatively, there are two separate phonological processing systems, the Hebrew subsystem being subordinate to the Russian one. In the case of the latter, the fragility of the system would have made it more susceptible to damage from cerebral hemorrhaging. Due to the limited nature of this study, no definitive conclusion could be reached on which of these two systems was more likely, it could only be deduced that after suffering trauma the subject was unable to access a Hebrew phoneme system. In other words, a late language learner with aphasia, and possibly all late language learners, use their first language as a crutch for interpreting their second language.

References:

Caramazza, A., Yeni-Komshian, G. H., Zurif, E. B., & Carbone, E. (1973). The acquisition of a new phonological contrast: The case of stop consonants in French-english bilinguals. Journal of Acoustical Society of America, 54(2), 421-428

de Bot, K. (1992). A bilingual production model: Levelt's "speaking" model adapted. Applied Linguistics, 13, 1-24.

de Groot, A. M. B. (1992). Determinants of word translation. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18, 1001-1018.

Kaplan, E., Goodglass, H., & Weintraub, S. (1983). Boston Naming Test. Philadelphia: Lea and Febiger.

Kertesz, A. (1982).Western aphasia battery. New York: Grune and Stratton.

Snodgrass, J. G., & Tsivkin, S. (1995). Organization of the bilingual lexicon: Categorical versus alphabetic cuing in Russian-English bilinguals. Journal of Psycholinguistic Research, 24, 145-162.

Spreen, O., & Strauss, E. (1991). A compendium of neuropsychological tests. New York: Oxford University Press.