Relationship between Behavioral Infant Speech Perception and Hearing Age for Children with Hearing Loss

(1) Background: Research has demonstrated that early intervention for children who are hard-of-hearing (CHH) facilitates improved language development. Early speech perception abilities may impact CHH outcomes and guide future intervention. The objective of this study was to examine the use of a conditioned head turn (CHT) task as a measure of speech discrimination in CHH using a clinically feasible protocol. (2) Methods: Speech perception was assessed for a consonant and vowel contrast among 57 CHH and 70 children with normal hearing (CNH) aged 5–17 months using a CHT paradigm. (3) Results: Regardless of hearing status, 74% of CHH and 77% of CNH could discriminate /a-i/, and 55% of CHH and 56% of CNH could discriminate /ba-da/. Regression models revealed that both CHH and CNH performed better on /ba-da/ at 70 dBA compared to 50 dBA. Performance by hearing age showed no speech perception differences for CNH and children with mild hearing loss for either contrast. However, children with hearing losses ≥ 41 dB HL performed significantly poorer than CNH for /a-i/. (4) Conclusions: This study demonstrates the clinical feasibility of assessing early speech perception in infants with hearing loss and replicates previous findings of speech perception abilities among CHH and CNH.

L1 phonological effects on L2 (non-)naïve perception: A cross-language investigation of the oral–nasal vowel contrast in Brazilian Portuguese

Feature-based approaches to acquisition principally focus on second language (L2) learners’ ability to perceive non-native consonants when the features required are either contrastively present or entirely absent from the first language (L1) grammar. As features may function contrastively or allophonically in the consonant and/or vowel systems of a language, we expand the scope of this research to address whether features that function contrastively in the L1 vowel system can be recombined to yield new vowels in the L2; whether features that play a contrastive role in the L1 consonant system can be reassigned to build new vowels in the L2; and whether L1 allophonic features can be ‘elevated’ to contrastive status in the L2. We examine perception of the oral–nasal contrast in Brazilian Portuguese listeners from French, English, Caribbean Spanish, and non-Caribbean Spanish backgrounds, languages that differ in the status assigned to [nasal] in their vowel systems. An AXB discrimination task revealed that, although all language groups succeeded in perceiving the non-naïve contrast /e/–/ẽ/ due to their previous exposure to Québec French while living in Montréal, Canada, only French and Caribbean Spanish speakers succeeded in discriminating the naïve contrast /i/–/ĩ/. These findings suggest that feature redeployment at first exposure is only possible if the feature is contrastive in the L1 vowel system (French) or if the feature is allophonic but variably occurs in contrastive contexts in the L1 vowel system (Caribbean Spanish). With more exposure to a non-native contrast, however, feature redeployment from consonant to vowel systems was also supported, as was the possibility that allophonic features may be elevated to contrastive status in the L2.

Does Studying in a Music-oriented Education Program Affect Non-native Sound Learning? — Effects of Passive Auditory Training on Children’s Vowel Production

Earlier studies have shown that children are efficient second language learners. Research has also shown that musical background might affect second language learning. A two-day auditory training paradigm was used to investigate whether studying in a music-oriented education program affects children’s sensitivity to acquire a non-native vowel contrast. Training effects were measured with listen-and-repeat production tests. Two groups of monolingual Finnish children (9–11 years, N=23) attending music-oriented and regular fourth grades were tested. The stimuli were two semisynthetic pseudo words /ty:ti/ and /tʉ:ti/ with the native vowel /y/ and the non-native vowel /ʉ/ embedded. Both groups changed their pronunciation after the first training. The change was reflected in the second formant values of /ʉ/, which lowered significantly after three trainings. The results show that 9–11-year-old children benefit from passive auditory training in second language production learning regardless of whether or not they attend a music-oriented education program.

Perception of Portuguese Mid Vowels by Heritage Speakers of Brazilian Portuguese

The main goal of this study is to investigate the perception of Portuguese mid-vowel contrasts (/ɛ/-/e/ and /ɔ/-/o/) by heritage speakers (HS s) of Brazilian Portuguese (BP) who grew up in the United States. This study shows, for instance, an asymmetry in categorization as a function of degree of language dominance for mid-back vowel contrast, but not for mid-front vowel contrast.

How Do Speakers of a Language with a Transparent Orthographic System Perceive the L2 Vowels of a Language with an Opaque Orthographic System? An Analysis through a Battery of Behavioral Tests

Background: The present study aims to investigate the effect of the first language (L1) orthography on the perception of the second language (L2) vowel contrasts and whether orthographic effects occur at the sublexical level. Methods: Fourteen adult Greek learners of English participated in two AXB discrimination tests: one auditory and one orthography test. In the auditory test, participants listened to triads of auditory stimuli that targeted specific English vowel contrasts embedded in nonsense words and were asked to decide if the middle vowel was the same as the first or the third vowel by clicking on the corresponding labels. The orthography test followed the same procedure as the auditory test, but instead, the two labels contained grapheme representations of the target vowel contrasts. Results: All but one vowel contrast could be more accurately discriminated in the auditory than in the orthography test. The use of nonsense words in the elicitation task eradicated the possibility of a lexical effect of orthography on auditory processing, leaving space for the interpretation of this effect on a sublexical basis, primarily prelexical and secondarily postlexical. Conclusions: L2 auditory processing is subject to L1 orthography influence. Speakers of languages with transparent orthographies such as Greek may rely on the grapheme–phoneme correspondence to decode orthographic representations of sounds coming from languages with an opaque orthographic system such as English.

Examining the Relationship Between Speech Perception, Production Distinctness, and Production Variability

Several studies have demonstrated that individuals’ ability to perceive a speech sound contrast is related to the production of that contrast in their native language. The theoretical account for this relationship is that speech perception and production have a shared multimodal representation in relevant sensory spaces (e.g., auditory and somatosensory domains). This gives rise to a prediction that individuals with more narrowly defined targets will produce greater separation between contrasting sounds, as well as lower variability in the production of each sound. However, empirical studies that tested this hypothesis, particularly with regard to variability, have reported mixed outcomes. The current study investigates the relationship between perceptual ability and production ability, focusing on the auditory domain. We examined whether individuals’ categorical labeling consistency for the American English /ε/–/æ/ contrast, measured using a perceptual identification task, is related to distance between the centroids of vowel categories in acoustic space (i.e., vowel contrast distance) and to two measures of production variability: the overall distribution of repeated tokens for the vowels (i.e., area of the ellipse) and the proportional within-trial decrease in variability as defined as the magnitude of self-correction to the initial acoustic variation of each token (i.e., centering ratio). No significant associations were found between categorical labeling consistency and vowel contrast distance, between categorical labeling consistency and area of the ellipse, or between categorical labeling consistency and centering ratio. These null results suggest that the perception-production relation may not be as robust as suggested by a widely adopted theoretical framing in terms of the size of auditory target regions. However, the present results may also be attributable to choices in implementation (e.g., the use of model talkers instead of continua derived from the participants’ own productions) that should be subject to further investigation.

Increased speech contrast induced by sensorimotor adaptation to a non-uniform auditory perturbation

When auditory feedback is perturbed in a consistent way, speakers learn to adjust their speech to compensate, a process known as sensorimotor adaptation. While this paradigm has been highly informative for our understanding of the role of sensory feedback in speech motor control, its ability to induce behaviorally-relevant changes in speech that affect communication effectiveness remains unclear. Because reduced vowel contrast contributes to intelligibility deficits in many neurogenic speech disorders, we examine human speakers' ability to adapt to a non-uniform perturbation field which was designed to affect vowel distinctiveness, applying a shift that depended on the vowel being produced. Twenty-five participants were exposed to this "vowel centralization" feedback perturbation in which the first to formant frequencies were shifted towards the center of each participant's vowel space, making vowels less distinct from one another. Speakers adapted to this non-uniform shift, learning to produce corner vowels with increased vowel space area and vowel contrast to partially overcome the perceived centralization. The increase in vowel contrast occurred without a concomitant increase in duration and persisted after the feedback shift was removed, including after a 10-minute silent period. These findings establish the validity of a sensorimotor adaptation paradigm to increase vowel contrast, showing that complex, non-uniform alterations to sensory feedback can successfully drive changes relevant to intelligible communication.