Individuals who learn two languages at an early age seem to switch back and forth between separate “sound systems” for each language, according to new research conducted at the University of Arizona.
The research, to be published in a forthcoming issue of Psychological Science, a journal of the Association for Psychological Science, addresses enduring questions in bilingual studies about how bilingual speakers hear and process sound in two different languages.
Kalim Gonzales’s research supports the view that bilinguals who learn two languages early in life learn two separate processing modes, or “sound systems.”
The study looked at 32 Spanish-English early bilinguals, who had learned their second language before age 8. Participants were presented with a series of pseudo-words beginning with a ‘pa’ or a ‘ba’ sound and asked to identify which of the two sounds they heard.
While ‘pa’ and ‘ba’ sounds exist in both English and Spanish, how those sounds are produced and perceived in the two languages varies subtly. In the case of ‘ba,’ for example, English speakers typically begin to vibrate their vocal chords the moment they open their lips, while Spanish speakers begin vocal chord vibration slightly before they open their lips and produce ‘pa’ in a manner similar to English ‘ba.’ As a result of those subtle differences, English-only speakers might, in some cases, confuse the ‘ba’ and ‘pa’ sounds they hear in Spanish.
For the study, the bilingual participants were divided into two groups. One group was told they would be hearing rare words in Spanish, while the other was told they would be hearing rare words in English. Both groups heard audio recordings of variations of the same two words — bafri and pafri — which are not real words in either language.
Participants were then asked to identify whether the words they heard began with a ‘ba’ or a ‘pa’ sound.
Each group heard the same series of words, but for the group told they were hearing Spanish, the ends of the words were pronounced slightly differently, with the ‘r’ getting a Spanish pronunciation.
The findings: Participants perceived ‘ba’ and ‘pa’ sounds differently depending on whether they were told they were hearing Spanish words, with the Spanish pronunciation of ‘r,’ or whether they were told they were hearing English words, with the English pronunciation of ‘r.’
When the study was repeated with 32 English monolinguals, participants did not show the same shift in perception; they labeled ‘ba’ and ‘pa’ sounds the same way regardless of which language they were told they were hearing. It was that lack of an effect for monolinguals that provided the strongest evidence for two sound systems in bilinguals.
These new findings challenge the idea that bilinguals always have one dominant language.