Traditionally,researchers have thought separately about the linguistic and indexical aspects of the signal. However, a fascinating, and robust, phenomenon is that listeners are better at identifying talkers who are speaking a familiar language than an unfamiliar language. The fascination with this phenomenon is due to the fact that it provides evidence that listeners integrate linguistic and indexical information in the course of speech processing. In a series of studies, I demonstrate that language experience and phonological processing exert a gradient influence on talker identification.
In an initial study, I compared the talker identification skills of adult monolingual English speakers who had very little exposure to French (by virtue of living in a highly monolingual city: Storrs, Connecticut) to those who had long-term systematic exposure to French (by virtue of living in a highly bilingual city: Montréal, Québec; Orena, Theodore,& Polka, 2015; Cognition). Results showed that, even in the absence of language comprehension, Montréal participants outperformed Connecticut participants in a talker identification task with French speakers. Similarly, we found that listeners still showed a talker familiarity effect for time-reversed speech – a manipulation that precludes lexical access (and thus, comprehension), but preserves some indexical and phonetic properties (Theodore, Monto, Orena, & Polka, under review). Together, my work shows that the language familiarity effect in talker identification begins with familiarity with the phonetic system.
Likewise, we found that talker identification across languages is also dependent on language experience (Orena, Polka, & Theodore, 2019; The Journal of the Acoustical Society of America). In this study,participants learned to identify bilingual talkers speaking in one of their languages and were then tested on their ability to identify the same talker when speaking their other language. Bilinguals - particularly those with more experience with language mixing - outperformed monolinguals in generalizing knowledge about the speaker's voice across their two languages.
Phonological processing also appears to play an important role for talker identification. In our study, we found reading-related differences in talker identification, with advanced readers showing overall better performance (Kadam, Orena, Theodore, & Polka, 2016; The Journal of the Acoustical Society of America). This work provides critical data in moving towards a principled account of the integration between talker identification and language abilities.
Theodore, R.M., Monto, N.R., Orena, A.J., &Polka, L. (revising to resubmit). The language familiarity effect for voice recognition is not contingent on lexical access.
Orena, A.J., Theodore, R.M., & Polka, L. (2019). Identifying bilingual talkers across languages: Language experience matters. Journal of the Acoustical Society of America, 145(4), EL303. doi:10.1121/1.5097735
Kadam, M.A., Orena, A.J., Theodore,R.M., & Polka, L. (2016). Reading ability influences native and non-native voice recognition, even for unimpaired readers. Journal of the Acoustical Society of America, 139(1), EL6-EL12. doi:10.1121/1.4937488
Orena, A.J., Theodore, R.M. & Polka, L. (2015). Language exposure facilitates talker learning prior to language comprehension, even in adults. Cognition,143, 36 - 40. doi:10.1016/j.cognition.2015.06.002