Speech Perception Development Research Articles

Development of fricative sound perception in Korean infants: The role of language experience and infants’ initial sensitivity

In this paper, we report data on the development of Korean infants’ perception of a rare fricative phoneme distinction. Korean fricative consonants have received much interest in the linguistic community due to the language’s distinct categorization of sounds. Unlike many fricative contrasts utilized in most of the world’s languages, Korean fricatives (/s*/-/s/) are all voiceless. Moreover, compared with other sound categories, fricatives have received very little attention in the speech perception development field and no studies thus far have examined Korean infants’ development of native phonology in this domain. Using a visual habituation paradigm, we tested 4‒6-month-old and 7‒9-month-old Korean infants on their abilities to discriminate the Korean fricative pair in the [a] vowel context, /s*a/-/sa/, which can be distinguished based on acoustic cues, such as the durations of aspiration and frication noise. Korean infants older than 7 months were able to reliably discriminate the fricative pair but younger infants did not show clear signs of such discrimination. These results add to the growing evidence that there are native sound contrasts infants cannot discriminate early on without a certain amount of language exposure, providing further data to help delineate the specific nature of early perceptual capacity.

Weighting of Amplitude and Formant Rise Time Cues by School-Aged Children: A Mismatch Negativity Study.

An important skill in the development of speech perception is to apply optimal weights to acoustic cues so that phonemic information is recovered from speech with minimum effort. Here, we investigated the development of acoustic cue weighting of amplitude rise time (ART) and formant rise time (FRT) cues in children as measured by mismatch negativity (MMN). Twelve adults and 36 children aged 6-12 years listened to a /ba/-/wa/ contrast in an oddball paradigm in which the standard stimulus had the ART and FRT cues of /ba/. In different blocks, the deviant stimulus had either the ART or FRT cues of /wa/. The results revealed that children younger than 10 years were sensitive to both ART and FRT cues whereas 10- to 12-year-old children and adults were sensitive only to FRT cues. Moreover, children younger than 10 years generated a positive mismatch response, whereas older children and adults generated MMN. These results suggest that preattentive adultlike weighting of ART and FRT cues is attained only by 10 years of age and accompanies the change from mismatch response to the more mature MMN response. https://doi.org/10.23641/asha.6207608.

Cascading and Multisensory Influences on Speech Perception Development

ABSTRACTOver the first weeks and months following birth, infants' initial, broad‐based perceptual sensitivities become honed to the characteristics of their native language. In this article, we review this process of emerging specialization within the context of a cascading “critical period” (CP) framework, in which periods of maximal openness to experience of different aspects of language occur at sequential, overlapping points in development. Importantly, as infants' experience of speech is not limited to auditory signals, but is informed by—for example—their experience of talking faces and their own oral motor movements, we review the trajectory of perceptual specialization in multisensory language processing. Throughout, we highlight the impact of increasing perceptual specialization on later language outcomes (e.g., word learning, foundations of syntax, literacy), and consider how the outcomes can be compromised if/when the timing of perceptual specialization has been perturbed.

Speech communication in older adults: an acoustic and perceptual investigation – ESRC

Speech communication can be difficult for older people, due to the combined effects of age-related hearing loss, which is common over the age of 65, age-related decline in the quality of phonation and speech articulation, and cognitive problems such as poorer short-term memory and processing speed. Past studies of how older individuals perceive and produce speech sounds have tended to consider these abilities independently of each other using controlled materials, such as read words or sentences. These studies tell us little about how older speakers function when using speech for communicative purposes, and how these various factors interact. In our project, we gained a comprehensive account of older people's speech production and perception in situations involving communication with another individual. Older adults with age-related hearing loss and the rarer group of older adults with normal hearing were included in the study, as well as younger adult controls. In Study 1, participants were recorded while they completed a problem-solving task with another person. Communication between the participants was either in good listening conditions, where both speakers could hear each other normally, or in adverse conditions. There, one of the participants had to get their message across to another speaker who has a simulated hearing loss or when both were speaking in a noisy background. These comparisons enabled us to get a sense of the degree to which an older person is able to adapt their speech to overcome difficult listening conditions, a skill which is of paramount importance in speech communication in everyday life. High-quality recordings were made of these interactions and these were used to carry out acoustic analyses of their speech and also analyses of interactional features such as eye gaze and turn-taking. In Study 2, older and younger listeners with normal and impaired hearing were presented some of the materials recorded in Study 1 in good and adverse listening conditions. Intelligibility tests will be run to see what impact age and hearing status have on speech understanding and to see whether the 'clear speech' adaptations made by older speakers to counter the effects of poor communication conditions gave the same benefit to that of younger speakers. This project aims to lead to a better understanding of the effects of ageing on speech communication and of the various contributing factors to potentially degraded speech communication in a population of 'healthy aged' individuals. These benchmarks will be of use for practitioners such as speech and language therapists and audiologists who work on aspects of communication with older people who have health complications. A better understanding of communication difficulties that older individuals experience and of their strategies to overcome these difficulties also assists professionals such as social workers and care professionals who work to improve quality of life for older people, as well as developers of speech technology devices for telemedicine and remote monitoring. Importantly, this research also contributes to our basic understanding of speech perception and production development across the lifespan.

What infant-directed speech tells us about the development of compensation for assimilation

In speech addressed to adults, words are seldom realized in their canonical, or citation, form. For example, the word ‘green’ in the phrase ‘green beans’ can often be realized as ‘greem’ due to English place assimilation, where word-final coronals take on the place of articulation of neighboring velars. In such a situation, adult listeners readily ‘undo’ the assimilatory process and perceive the underlying intended lexical form of ‘greem’ (i.e. they access the lexical representation ‘green’). An interesting developmental question is how children, with their limited lexical knowledge, come to cope with phonologically conditioned connected speech processes such as place assimilation. Here, we begin to address this issue by examining the occurrence of place assimilation in the input to English-learning 18-month-olds. Perceptual and acoustic analyses of elicited speech, as well asanalysis of a corpus of spontaneous speech, all converge on the finding that caregivers do not spoon-feed their children canonical tokens of words. Rather, infant-directed speech contains just as many non-canonical realizations of words in place assimilation contexts asadult-directed speech. Implications for models of developmental speech perception are discussed.

Mandarin-Speaking Children's Speech Recognition: Developmental Changes in the Influences of Semantic Context and F0 Contours.

The goal of this developmental speech perception study was to assess whether and how age group modulated the influences of high-level semantic context and low-level fundamental frequency (F0) contours on the recognition of Mandarin speech by elementary and middle-school-aged children in quiet and interference backgrounds. The results revealed different patterns for semantic and F0 information. One the one hand, age group modulated significantly the use of F0 contours, indicating that elementary school children relied more on natural F0 contours than middle school children during Mandarin speech recognition. On the other hand, there was no significant modulation effect of age group on semantic context, indicating that children of both age groups used semantic context to assist speech recognition to a similar extent. Furthermore, the significant modulation effect of age group on the interaction between F0 contours and semantic context revealed that younger children could not make better use of semantic context in recognizing speech with flat F0 contours compared with natural F0 contours, while older children could benefit from semantic context even when natural F0 contours were altered, thus confirming the important role of F0 contours in Mandarin speech recognition by elementary school children. The developmental changes in the effects of high-level semantic and low-level F0 information on speech recognition might reflect the differences in auditory and cognitive resources associated with processing of the two types of information in speech perception.

Auditory-visual speech perception in three- and four-year-olds and its relationship to perceptual attunement and receptive vocabulary.

Despite the body of research on auditory-visual speech perception in infants and schoolchildren, development in the early childhood period remains relatively uncharted. In this study, English-speaking children between three and four years of age were investigated for: (i) the development of visual speech perception - lip-reading and visual influence in auditory-visual integration; (ii) the development of auditory speech perception and native language perceptual attunement; and (iii) the relationship between these and a language skill relevant at this age, receptive vocabulary. Visual speech perception skills improved even over this relatively short time period. However, regression analyses revealed that vocabulary was predicted by auditory-only speech perception, and native language attunement, but not by visual speech perception ability. The results suggest that, in contrast to infants and schoolchildren, in three- to four-year-olds the relationship between speech perception and language ability is based on auditory and not visual or auditory-visual speech perception ability. Adding these results to existing findings allows elaboration of a more complete account of the developmental course of auditory-visual speech perception.

Perceptual Improvement of Lexical Tones in Infants: Effects of Tone Language Experience.

To learn words in a tonal language, tone-language learners should not only develop better abilities for perceiving consonants and vowels, but also for lexical tones. The divergent trend of enhancing sensitivity to native phonetic contrasts and reduced sensitivity to non-native phonetic contrast is theoretically essential to evaluate effects of listening to an ambient language on speech perception development. The loss of sensitivity in discriminating lexical tones among non-tonal language-learning infants was apparent between 6 and 12 months of age, but only few studies examined trends of differentiating native lexical tones in infancy. The sensitivity in discriminating lexical tones among 6–8 and 10–12 month-old Mandarin-learning infants (n = 120) was tested in Experiment 1 using three lexical tone contrasts of Mandarin. Facilitation of linguistic experience was shown in the tonal contrast (Tone 1 vs. 3), but both age groups performed similar in the other two tonal contrasts (Tone 2 vs. 4; Tone 2 vs. 3). In Experiment 2, 6–8 and 10–12 month-old Mandarin-learning infants (n = 90) were tested with tonal contrasts that have pitch contours either similar to or inverse from lexical tones in Mandarin, and perceptual improvement was shown only in a tonal contrast with familiar pitch contours (i.e., Tone 1 vs. 3). In Experiment 3, 6–8 and 10–12 month-old English-learning infants (n = 40) were tested with Tone 1 vs. 3 contrast of Mandarin and showed an improvement in the perception of non-native lexical tones. This study reveals that tone-language learning infants develop more accurate representations of lexical tones around their first birthday, and the results of both tone and non-tone language-learning infants imply that the rate of development depends on listening experience and the acoustical salience of specific tone contrasts.

T-complex measures in bilingual Spanish-English and Turkish-German children and monolingual peers.

BackgroundLateral temporal neural measures (Na and T-complex Ta and Tb) of the auditory evoked potential (AEP) index maturation of auditory/speech processing. These measures are also sensitive to language experience in adults. This paper examined neural responses to a vowel sound at temporal electrodes in four- to five-year-old Spanish-English bilinguals and English monolinguals and in five- to six-year-old Turkish-German bilinguals and German monolinguals. The goal was to determine whether obligatory AEPs at temporal electrode sites were modulated by language experience. Language experience was defined in terms of monolingual versus bilingual status as well as the amount and quality of the bilingual language experience.MethodAEPs were recorded at left and right temporal electrode sites to a 250-ms vowel [Ɛ] from 20 monolingual (American)-English and 18 Spanish-English children from New York City, and from 11 Turkish-German and 13 monolingual German children from Ulm, Germany. Language background information and standardized verbal and non-verbal test scores were obtained for the children.ResultsThe results revealed differences in temporal AEPs (Na and Ta of the T-complex) between monolingual and bilingual children. Specifically, bilingual children showed smaller and/or later peak amplitudes than the monolingual groups. Ta-amplitude distinguished monolingual and bilingual children best at right electrode sites for both the German and American groups. Amount of experience and type of experience with the target language (English and German) influenced processing.ConclusionsThe finding of reduced amplitudes at the Ta latency for bilingual compared to monolingual children indicates that language specific experience, and not simply maturational factors, influences development of the neural processes underlying the Ta AEP, and suggests that lateral temporal cortex has an important role in language-specific speech perception development.

The development of visual speech perception in Mandarin Chinese-speaking children

ABSTRACTThe present study aimed to investigate the development of visual speech perception in Chinese-speaking children. Children aged 7, 13 and 16 were asked to visually identify both consonant and vowel sounds in Chinese as quickly and accurately as possible. Results revealed (1) an increase in accuracy of visual speech perception between ages 7 and 13 after which the accuracy rate either stagnates or drops; and (2) a U-shaped development pattern in speed of perception with peak performance in 13-year olds. Results also showed that across all age groups, the overall levels of accuracy rose, whereas the response times fell for simplex finals, complex finals and initials. These findings suggest that (1) visual speech perception in Chinese is a developmental process that is acquired over time and is still fine-tuned well into late adolescence; (2) factors other than cross-linguistic differences in phonological complexity and degrees of reliance on visual information are involved in development of visual speech perception.

FORMATION AND DEVELOPMENT OF SPEECH PERCEPTION AMONG MINORITY PRIMARY SCHOOL CHILDREN WITH SPECIFIC LANGUAGE IMPAIRMENT

Development of speech perception among schoolchildren having specific language impairment is one of the most important profiles in the work of the speech therapist.Aim of research: to research methods used by a speech therapist in work aimed at the formation and development of speech perception among schoolchildren having specific language impairment, to work out and approbate the material developed for a speech therapist’s work. While developing speech perception, the exercises are becoming more and more serious and even complicated. However, if they are offered to a schoolchild gradually or in a form of a game and if the structure of the disorder of each child alongside with his individual features are taken into account and the cooperation with parents is established, any child can essentially improve the level of his speech perception. Having analyzed the approaches to the logopedic correction work aimed at speech development and findings of other speech therapists having practice and experience in this field, the author of the given research has worked out her methodological material, i.e. a workbook “A hundred exercises for the formation and development of speech perception among minority primary school children with specific language impairment”.

“Never too late to spot a difference”: the development of L2 speech perception in adults

Abstract Learning correct pronunciation of a second/foreign language always represents a considerable challenge for language learners (e.g. Rojczyk, 2010a), especially for adults (e.g. Flege, 2007). There is an abundance of studies (e.g. Nowacka, 2010; Flege, 1991) showing that second language learners whose first language (L1) phonetic system has only one sound where L2 is characterized by noticeable richness of separate sound categories, encounter serious problems when they try to distinguish those new sounds and, moreover, they tend to apply their native vowels or consonants in L2 speech. It may be easily audible in the case of vowels and actually a lot of studies on L2 learners’ production and perception of L1 and L2 vowels have been carried (e.g. Flege, 1992; Nowacka, 2010; Rojczyk, 2010a; Rojczyk, 2010b). The aim of this study was to examine elementary learners’ perception of 4 German vowels, namely: /ɪ/, /iː/, /ʏ/ and /yː/. They were organized as two sets of minimal pairs, namely /ɪ/ vs. /ʏ/ and /iː/ vs. /yː/. The aforementioned sounds were chosen for the study since /ʏ/ and /yː/ are considered to be very difficult vowels for Polish learners (e.g. Bęza, 2001). Twelve elementary, adult (29-52 years old) Polish learners of German agreed to participate in the study. The subjects had just began their A2-level language course, however they had been taught the basics of German pronunciation for a year, during their A1-level course. They were presented a printed list of word pairs and listened to the recorded words. Then they were asked to circle the right option in each pair. The results revealed that although all study participants were adults when they started learning German and they were still just elementary users of the language, they were already able to distinguish correctly a considerable number of words. It may suggest that proper pronunciation training during a FL/L2 course can provide language learners with measurable benefits.

Vocabulary development in Mandarin-speaking children with cochlear implants and its relationship with speech perception abilities

BackgroundChina has the largest population of children with hearing impairments and cochlear implantation is gaining popularity there. However, the vocabulary development in this population is largely unexplored. AimsThis study examined early vocabulary outcomes, factors influencing early vocabulary development and the relationship between speech perception and vocabulary development in Mandarin-speaking children during the first year of cochlear implant use. Methods and proceduresA battery of vocabulary tests was administered to 80 children before implantation and 3, 6, and 12 months after implantation. Demographic information was obtained to evaluate their relationships with vocabulary outcomes. Outcomes and resultsThe Mandarin-speaking children, who received their cochlear implants before 3 years of age, developed vocabulary at a rate faster than that of their same-aged peers with normal hearing. Better pre-implant hearing levels, younger age at implantation, and higher maternal education level contributed to the early vocabulary development. The trajectories of speech perception development highly correlated with those of vocabulary development during 3 to 12 months of CI use. Conclusionsand Implications: These findings imply that the vocabulary development of children implanted before 3 years of age may catch up with that of their hearing peers.

Auditory Speech Perception Development in Relation to Patient's Age with Cochlear Implant.

Introduction A cochlear implant in adolescent patients with pre-lingual deafness is still a debatable issue. Objective The objective of this study is to analyze and compare the development of auditory speech perception in children with pre-lingual auditory impairment submitted to cochlear implant, in different age groups in the first year after implantation. Method This is a retrospective study, documentary research, in which we analyzed 78 reports of children with severe bilateral sensorineural hearing loss, unilateral cochlear implant users of both sexes. They were divided into three groups: G1, 22 infants aged less than 42 months; G2, 28 infants aged between 43 to 83 months; and G3, 28 older than 84 months. We collected medical record data to characterize the patients, auditory thresholds with cochlear implants, assessment of speech perception, and auditory skills. Results There was no statistical difference in the association of the results among groups G1, G2, and G3 with sex, caregiver education level, city of residence, and speech perception level. There was a moderate correlation between age and hearing aid use time, age and cochlear implants use time. There was a strong correlation between age and the age cochlear implants was performed, hearing aid use time and age CI was performed. Conclusion There was no statistical difference in the speech perception in relation to the patient's age when cochlear implant was performed. There were statistically significant differences for the variables of auditory deprivation time between G3 - G1 and G2 - G1 and hearing aid use time between G3 - G2 and G3 - G1.

Factors Affecting Speech Discrimination in Children with Cochlear Implants: Evidence from Early-Implanted Infants.

To learn words and acquire language, children must be able to discriminate and correctly perceive phonemes. Although there has been much research on the general language outcomes of children with cochlear implants (CIs), little is known about the development of speech perception with regard to specific speech processes, such as speech discrimination. The purpose of this study was to investigate the development of speech discrimination in infants with CIs and identify factors that might correlate with speech discrimination skills. Using a Hybrid Visual Habituation procedure, we tested infants with CIs on their ability to discriminate the vowel contrast /i/-/u/. We also gathered demographic and audiological information about each infant. Children who had received CIs before 2 yr of age served as participants. We tested the children at two post cochlear implantation intervals: 2-4 weeks post CI stimulation (N = 17) and 6-9 mo post CI stimulation (N = 10). The infants' mean looking times during the novel versus old trials of the experiment were measured. A linear regression model was used to evaluate the relationship between the normalized looking time difference and the following variables: chronological age, age at CI stimulation, gender, communication mode, and best unaided pure-tone average. We found that the best unaided pure-tone average predicted speech discrimination at the early interval. In contrast to some previous speech perception studies that included children implanted before 3 yr of age, age at CI stimulation did not predict speech discrimination performance. The results suggest that residual acoustic hearing before implantation might facilitate speech discrimination during the early period post cochlear implantation; with more hearing experience, communication mode might have a greater influence on the ability to discriminate speech. This and other studies on age at cochlear implantation suggest that earlier implantation might not have as large an effect on speech perception as it does on other language skills.

Audiovisual speech perception development at varying levels of perceptual processing

This study used the auditory evaluation framework [Erber (1982). Auditory Training (Alexander Graham Bell Association, Washington, DC)] to characterize the influence of visual speech on audiovisual (AV) speech perception in adults and children at multiple levels of perceptual processing. Six- to eight-year-old children and adults completed auditory and AV speech perception tasks at three levels of perceptual processing (detection, discrimination, and recognition). The tasks differed in the level of perceptual processing required to complete them. Adults and children demonstrated visual speech influence at all levels of perceptual processing. Whereas children demonstrated the same visual speech influence at each level of perceptual processing, adults demonstrated greater visual speech influence on tasks requiring higher levels of perceptual processing. These results support previous research demonstrating multiple mechanisms of AV speech processing (general perceptual and speech-specific mechanisms) with independent maturational time courses. The results suggest that adults rely on both general perceptual mechanisms that apply to all levels of perceptual processing and speech-specific mechanisms that apply when making phonetic decisions and/or accessing the lexicon. Six- to eight-year-old children seem to rely only on general perceptual mechanisms across levels. As expected, developmental differences in AV benefit on this and other recognition tasks likely reflect immature speech-specific mechanisms and phonetic processing in children.

Auditory and visual information in speech perception: A developmental perspective

ABSTRACTThis study investigates the development of audiovisual speech perception from age 4 to 80, analysing the contribution of modality, context and special features of specific language being tested. Data of 77 participants in five age groups is presented in the study. Speech stimuli were introduced via auditory, visual and audiovisual modalities. Monosyllabic meaningful and nonsense words were included in a signal-to-noise ratio of 0 dB. Speech perception accuracy in audiovisual and auditory modalities by age resulted in an inverse U-shape, with lowest performance at ages 4–5 and 65–80. In the visual modality, a clear difference was shown between performance of children (ages 4–5 and 8–9) and adults (age 20 and above). The findings of the current study have important implications for strategic planning in rehabilitation programmes for child and adult speakers of different languages with hearing difficulties.

Adaptation and validation of Common Object Token (COT) test into the Sinhalese language

ObjectivesThis manuscript presents a translation and adaptation of the Common Object Token (COT) test, which assesses speech perception, into the Sinhalese language and an attempt to validate it for use on children with normal hearing (NH) and children with a cochlear implant (CI). MethodsNinety-five children (70 with NH, 25 with a CI) participated in the study. The COT test was translated, back-translated, and evaluated by a team of experts until the Sinhalese translation was deemed acceptable. Data of Sinhalese children with NH and values of children with a CI were analysed. Internal reliability and consistency of the COT total score were determined. Lastly, a quick version of the COT test was created. ResultsThe total mean scores and subtest mean scores improved with age for children with NH. For children with a CI, a strong relationship between the COT total score and device experience, i.e. hearing age, was found. A Quick Sinhalese COT test version, suitable for children with a CI, could be created from Subtests 2, 3, and 4. ConclusionThe Sinhalese COT test is valid for assessing the age-related development of speech perception and identification skills of children with NH. Results suggest that the COT is valid for use in children with a CI.

Audiovisual speech perception in infancy: The influence of vowel identity and infants' productive abilities on sensitivity to (mis)matches between auditory and visual speech cues.

Recent studies suggest that infants' audiovisual speech perception is influenced by articulatory experience (Mugitani et al., 2008; Yeung & Werker, 2013). The current study extends these findings by testing if infants' emerging ability to produce native sounds in babbling impacts their audiovisual speech perception. We tested 44 6-month-olds on their ability to detect mismatches between concurrently presented auditory and visual vowels and related their performance to their productive abilities and later vocabulary size. Results show that infants' ability to detect mismatches between auditory and visually presented vowels differs depending on the vowels involved. Furthermore, infants' sensitivity to mismatches is modulated by their current articulatory knowledge and correlates with their vocabulary size at 12 months of age. This suggests that-aside from infants' ability to match nonnative audiovisual cues (Pons et al., 2009)-their ability to match native auditory and visual cues continues to develop during the first year of life. Our findings point to a potential role of salient vowel cues and productive abilities in the development of audiovisual speech perception, and further indicate a relation between infants' early sensitivity to audiovisual speech cues and their later language development.

Early speech perception in Mandarin-speaking children at one-year post cochlear implantation

PurposeThe aim in this study was to examine early speech perception outcomes in Mandarin-speaking children during the first year of cochlear implant (CI) use. MethodA hierarchical early speech perception battery was administered to 80 children before and 3, 6, and 12 months after implantation. Demographic information was obtained to evaluate its relationship with these outcomes. ResultsRegardless of dialect exposure and whether a hearing aid was trialed before implantation, implant recipients were able to attain similar pre-lingual auditory skills after 12 months of CI use. Children speaking Mandarin developed early Mandarin speech perception faster than those with greater exposure to other Chinese dialects. In addition, children with better pre-implant hearing levels and younger age at implantation attained significantly better speech perception scores after 12 months of CI use. Better pre-implant hearing levels and higher maternal education level were also associated with a significantly steeper growth in early speech perception ability. ConclusionsMandarin-speaking children with CIs are able to attain early speech perception results comparable to those of their English-speaking counterparts. In addition, consistent single language input via CI probably enhances early speech perception development at least during the first-year of CI use.