2018 Saturday Symposium

Saturday, November 3, 2018 | Saturday Symposium, Metcalf Large | 12:15pm

Saturday Symposium: “A developmental, individual-differences perspective on processing of and learning from accented speech”

Toddlers’ accommodation of accent: Acoustic and experiential factors
Rochelle Newman (University of Maryland)

Effects of bilingualism on children’s processing of accented speech
Margarita Kaushanskaya (University of Wisconsin – Madison)

Individual differences in perception of non-native speech
Melissa Baese-Berk (University of Oregon)

Symposium

An important skill in learning and processing language is the ability to generalize across variations present in the speech signal. Variation comes from many sources, including differences across talkers, rate of speech, and context – but one major source of variation is caused by differences across accents. Two sets of findings have dominated the literature on processing of accented speech: First, we know that accented speech (including regional and foreign accents) is more difficult to understand than native speech. Second, we know that over a relatively brief period of time, listener adapt to unfamiliar accents. However, important unknowns remain. For instance, what is it about accent, in acoustic terms, that poses processing difficulties? What accounts for wide individual differences in processing of and accommodation to accented speech? What are the factors that enhance accommodation to accented speech?  And how do these factors change with development?

In this symposium, we propose to tackle these questions through a unique approach. We all conduct research on accented speech. However, we work with distinct age groups (infants, school-aged children, and adults). Therefore together, we can begin to address possible developmental differences in accented speech processing. Further, while most research on accented speech processing takes a monolingual mind as the default cognitive model, in our work we consider the possibility that bilingual experience may alter the ability to accommodate to accented speech, and examine how it may do so. We also recognize wide individual differences in the ability to process accented speech, and carefully consider factors that may contribute to this variability. Finally, comprehension of accented speech and learning from it may place distinct demands on the cognitive system, and in our work, we examine both processes. Across studies in our labs, we have observed important convergences, but also important divergences. By taking a developmental, individual-differences perspective on processing of and learning from accented speech, we can begin to address the inconsistent findings across labs. Practically, both children and adults encounter accented speakers in their daily lives, and while processing of accented speech is challenging for both age groups, children, whose language system is less stable, may be particularly sensitive to the effects of accented speech. The question then is: Does exposure to accented speech pose risks for language development?

Individual contributions are outlined below:

Melissa Baese-Berk. There is substantial variability in how well an individual is able to understand non-native speech. That is, some listeners are quite good at this task, even with relatively little experience, while others are comparatively quite poor. In our work, we have investigated two questions. First, does the ability to understand non-native speech correlate with the ability to understand speech in other challenging circumstances (i.e., unfamiliar native accents, speech-in-noise)? Second, is the ability to understand non-native speech predicted by other cognitive and linguistic skills (e.g., vocabulary size, working memory)? The results of our studies suggest a complex interplay of factors influence an individual’s ability to understand non-native speech. In current work, we examine what factors of the non-native speech, per se, may allow particular listeners to better understand and adapt to a non-native accent. For example, it is possible that if speakers differ from the native talker norm, but are very consistent within their own productions, they may be easier for some listeners to understand.

Rochelle Newman. Accents can pose multiple problems for a young learner:  First, phonetic and rhythmic variations can potentially make the mapping between accents difficult.  Second, speakers with foreign accents may be less consistent across their productions. Third, some accents may have sufficiently large acoustic differences that they can cause a perceived change in category identity resulting in overlap between intended categories. Recent work from our lab has revealed that: 1) toddlers’ (aged 18-20 months) ability to generalize across accents appears to be affected more by dialectal changes in vowel realizations than by changes in linguistic rhythm; 2) children aged 32 months can successfully accommodate accents that do not result in category overlap, but have more difficulty when accents have the potential to cause phonetic confusions, and 3) bilingual children are better able to generalize across unfamiliar regional dialects than monolingual children. We have also found that while children’s recognition of known words is impaired by the presence of an accent, their short-term memory is not. That is, assuming a word was identified correctly when it was spoken, the presence of an accent does not appear to further affect children’s ability to store that information for subsequent recall. These findings support a more nuanced view of the way that children both accommodate, and are affected by, variation in their language input.

Margarita Kaushanskaya. Laboratory studies of accommodation to accented speech suggest that a relatively short period of pre-exposure is needed for children to accommodate to an unfamiliar accented speaker. Therefore, one intuitive prediction is that experience with accented speech in daily life should also lead to easier accommodation. We have tested this prediction by comparing bilingual and monolingual children (ages 4-6) in their ability to both process and learn words from accented speech.  We found: 1) accented speech poses similar processing difficulties for both bilingual and monolingual children, despite bilinguals’ familiarity with foreign accent; and 2) accented speech poses more of a learning challenge for monolingual than for bilingual children. In our word-learning studies, bilingual children have just as much difficulty learning novel words from a speaker who speaks in an unfamiliar foreign accent, but have significantly less difficulty learning novel words from a speaker who shares their native language, and thus speaks with a familiar foreign accent. While there are significant individual differences both processing and learning performance, this is not predicted by children’s language ability. We are currently testing bilingual and monolingual children with typical language and with language impairment on word-learning tasks, with the goal of examining whether accented input poses a risk for children with weak language skills