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O gesto fônico na aquisição "desviante" : movimentos entre a produção e a percepção; The articulatory gesture in "deviant" phonological acquisition : moving between production and perception

Maria Claudia Camargo de Freitas
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 24/02/2012 PT
Relevância na Pesquisa
56.3%
A proposta deste trabalho consistiu em resgatar marcas da reorganização fônica em crianças com diagnóstico de transtorno fonológico, à luz da Fonologia Gestual. Em especial, marcas que evidenciassem uma relação especial entre fluência oral e processos fônicos. A fim de obter uma amostra significativa de momentos de reorganização fônica, foram coletados longitudinalmente dados de produção e, também, de percepção de fala. Para compor o grupo alvo (GA), selecionaram-se quatro crianças com dificuldades nas obstruintes surdas - classe de sons escolhida para uniformizar a amostra - e, para o grupo controle (GC), quatro crianças sem alterações fônicas - com idade e gênero compatíveis aos do GA. O corpus de produção foi composto por realizações de palavras-alvo iniciadas pelos fones obstruintes desvozeados seguidos das vogais [a], [i] ou [u] inseridas em uma frase-veículo. Gravações realizadas em cabine acústica por meio de equipamento digital de alta fidelidade. Utilizouse para analisá-los, as análises de outiva e acústica - momentos espectrais e medidas de duração. Sobre a percepção de fala, foi realizada uma tarefa XAB composta por estímulos naturais que continham sílabas iniciadas por obstruintes desvozeadas seguidas de [a]. Foram realizadas quatro coletas...

Cross-language perception and production of English vowels by Portuguese learners : the effects of perceptual training

Rato, Anabela Alves dos Santos
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em /01/2014 ENG
Relevância na Pesquisa
46.27%
Doctoral Dissertation in Language Sciences Specialization in English Linguistics; Several studies have demonstrated that second/foreign language (L2/FL) speech learning is a challenge to late learners (i.e., adolescents or adults) in terms of perception and production of certain non-native phonemic and phonetic contrasts (Moyer, 2013). The interaction of different factors might explain learners’ difficulties, namely age of onset of learning (AOL), amount of native (L1) and non-native language (NNL) use over time, quantity and quality of NNL input, and the interference from the L1 phonological system (Piske, 2007). The Speech Learning Model (SLM), proposed by Flege (1995), hypothesizes that difficulties in perceiving and, consequently, in producing non-native contrasts are due to the (dis)similarities between the L1 and the NNL phonological systems. The L1 sound system is likely to hinder the formation of new non-native (L2/FL) phonological categories. However, a considerable number of cross-language studies has revealed that phonological learning is attainable for late learners, and their abilities in perceiving and producing segmental and suprasegmental non-native contrasts can improve, since the mechanisms used in the acquisition of the L1 sound system remain intact over the lifespan and can be applied to L2/FL learning (Flege...

Audiological outcomes of cochlear implantation in Waardenburg Syndrome

Magalhães,Ana Tereza de Matos; Samuel,Paola Angélica; Goffi-Gomez,Maria Valeria Schimdt; Tsuji,Robinson Koji; Brito,Rubens; Bento,Ricardo Ferreira
Fonte: Fundação Otorrinolaringologia Publicador: Fundação Otorrinolaringologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
Relevância na Pesquisa
56.21%
INTRODUCTION: The most relevant clinical symptom in Waardenburg syndrome is profound bilateral sensorioneural hearing loss. AIM: To characterize and describe hearing outcomes after cochlear implantation in patients with Waardenburg syndrome to improve preoperative expectations. METHOD: This was an observational and retrospective study of a series of cases. Children who were diagnosed with Waardenburg syndrome and who received a multichannel cochlear implant between March 1999 and July 2012 were included in the study. Intraoperative neural response telemetry, hearing evaluation, speech perception, and speech production data before and after surgery were assessed. RESULTS: During this period, 806 patients received a cochlear implant and 10 of these (1.2%) were diagnosed with Waardenburg syndrome. Eight of the children received a Nucleus 24® implant and 1 child and 1 adult received a DigiSonic SP implant. The mean age at implantation was 44 months among the children. The average duration of use of a cochlear implant at the time of the study was 43 months. Intraoperative neural responses were present in all cases. Patients who could use the speech processor effectively had a pure tone average of 31 dB in free-field conditions. In addition...

Functional overlap between regions involved in speech perception and in monitoring one’s own voice during speech production

Zheng, Zane Z.; Munhall, Kevin G; Johnsrude, Ingrid S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2010 EN
Relevância na Pesquisa
46.27%
The fluency and reliability of speech production suggests a mechanism that links motor commands and sensory feedback. Here, we examine the neural organization supporting such links by using fMRI to identify regions in which activity during speech production is modulated according to whether auditory feedback matches the predicted outcome or not, and examining the overlap with the network recruited during passive listening to speech sounds. We use real-time signal processing to compare brain activity when participants whispered a consonant-vowel-consonant word (‘Ted’) and either heard this clearly, or heard voice-gated masking noise. We compare this to when they listened to yoked stimuli (identical recordings of ‘Ted’ or noise) without speaking. Activity along the superior temporal sulcus (STS) and superior temporal gyrus (STG) bilaterally was significantly greater if the auditory stimulus was a) processed as the auditory concomitant of speaking and b) did not match the predicted outcome (noise). The network exhibiting this Feedback type by Production/Perception interaction includes an STG/MTG region that is activated more when listening to speech than to noise. This is consistent with speech production and speech perception being linked in a control system that predicts the sensory outcome of speech acts...

Hearing Lips and Seeing Voices: How Cortical Areas Supporting Speech Production Mediate Audiovisual Speech Perception

Skipper, Jeremy I.; van Wassenhove, Virginie; Nusbaum, Howard C.; Small, Steven L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.31%
Observing a speaker’s mouth profoundly influences speech perception. For example, listeners perceive an “illusory” “ta” when the video of a face producing /ka/ is dubbed onto an audio /pa/. Here, we show how cortical areas supporting speech production mediate this illusory percept and audiovisual (AV) speech perception more generally. Specifically, cortical activity during AV speech perception occurs in many of the same areas that are active during speech production. We find that different perceptions of the same syllable and the perception of different syllables are associated with different distributions of activity in frontal motor areas involved in speech production. Activity patterns in these frontal motor areas resulting from the illusory “ta” percept are more similar to the activity patterns evoked by AV/ta/ than they are to patterns evoked by AV/pa/ or AV/ka/. In contrast to the activity in frontal motor areas, stimulus-evoked activity for the illusory “ta” in auditory and somatosensory areas and visual areas initially resembles activity evoked by AV/pa/ and AV/ka/, respectively. Ultimately, though, activity in these regions comes to resemble activity evoked by AV/ta/. Together, these results suggest that AV speech elicits in the listener a motor plan for the production of the phoneme that the speaker might have been attempting to produce...

On the context-dependent nature of the contribution of the ventral premotor cortex to speech perception

Tremblay, Pascale; Small, Steven L.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.4%
What is the nature of the interface between speech perception and production, where auditory and motor representations converge? One set of explanations suggests that during perception, the motor circuits involved in producing a perceived action are in some way enacting the action without actually causing movement (covert simulation) or sending along the motor information to be used to predict its sensory consequences (i.e., efference copy). Other accounts either reject entirely the involvement of motor representations in perception, or explain their role as being more supportive than integral, and not employing the identical circuits used in production. Using fMRI, we investigated whether there are brain regions that are conjointly active for both speech perception and production, and whether these regions are sensitive to articulatory (syllabic) complexity during both processes, which is predicted by a covert simulation account. A group of healthy young adults (1) observed a female speaker produce a set of familiar words (perception), and (2) observed and then repeated the words (production). There were two types of words, varying in articulatory complexity, as measured by the presence or absence of consonant clusters. The simple words contained no consonant cluster (e.g. “palace”)...

Speech perception and production

Casserly, Elizabeth D.; Pisoni, David B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.26%
Until recently, research in speech perception and speech production has largely focused on the search for psychological and phonetic evidence of discrete, abstract, context-free symbolic units corresponding to phonological segments or phonemes. Despite this common conceptual goal and intimately related objects of study, however, research in these two domains of speech communication has progressed more or less independently for more than 60 years. In this article, we present an overview of the foundational works and current trends in the two fields, specifically discussing the progress made in both lines of inquiry as well as the basic fundamental issues that neither has been able to resolve satisfactorily so far. We then discuss theoretical models and recent experimental evidence that point to the deep, pervasive connections between speech perception and production. We conclude that although research focusing on each domain individually has been vital in increasing our basic understanding of spoken language processing, the human capacity for speech communication is so complex that gaining a full understanding will not be possible until speech perception and production are conceptually reunited in a joint approach to problems shared by both modes.

Sensory-motor transformations for speech occur bilaterally

Cogan, Gregory B.; Thesen, Thomas; Carlson, Chad; Doyle, Werner; Devinsky, Orrin; Pesaran, Bijan
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.38%
Historically, the study of speech processing has emphasized a strong link between auditory perceptual input and motor production output1–4. A kind of ‘parity’ is essential, as both perception- and production-based representations must form a unified interface to facilitate access to higher order language processes such as syntax and semantics, believed to be computed in the dominant, typically left hemisphere5,6. While various theories have been proposed to unite perception and production2,7, the underlying neural mechanisms are unclear. Early models of speech and language processing proposed that perceptual processing occurred in the left posterior superior temporal gyrus (Wernicke’s area) and motor production processes occurred in the left inferior frontal gyrus (Broca’s area)8,9. Sensory activity was proposed to link to production activity via connecting fiber tracts, forming the left lateralized speech sensory-motor system10. While recent evidence indicates that speech perception occurs bilaterally11–13, prevailing models maintain that the speech sensory-motor system is left lateralized11,14–18 and facilitates the transformation from sensory-based auditory representations to motor-based production representations11...

Temporal dynamics of sensorimotor integration in speech perception and production: independent component analysis of EEG data

Jenson, David; Bowers, Andrew L.; Harkrider, Ashley W.; Thornton, David; Cuellar, Megan; Saltuklaroglu, Tim
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 10/07/2014 EN
Relevância na Pesquisa
56.18%
Activity in anterior sensorimotor regions is found in speech production and some perception tasks. Yet, how sensorimotor integration supports these functions is unclear due to a lack of data examining the timing of activity from these regions. Beta (~20 Hz) and alpha (~10 Hz) spectral power within the EEG μ rhythm are considered indices of motor and somatosensory activity, respectively. In the current study, perception conditions required discrimination (same/different) of syllables pairs (/ba/ and /da/) in quiet and noisy conditions. Production conditions required covert and overt syllable productions and overt word production. Independent component analysis was performed on EEG data obtained during these conditions to (1) identify clusters of μ components common to all conditions and (2) examine real-time event-related spectral perturbations (ERSP) within alpha and beta bands. 17 and 15 out of 20 participants produced left and right μ-components, respectively, localized to precentral gyri. Discrimination conditions were characterized by significant (pFDR < 0.05) early alpha event-related synchronization (ERS) prior to and during stimulus presentation and later alpha event-related desynchronization (ERD) following stimulus offset. Beta ERD began early and gained strength across time. Differences were found between quiet and noisy discrimination conditions. Both overt syllable and word productions yielded similar alpha/beta ERD that began prior to production and was strongest during muscle activity. Findings during covert production were weaker than during overt production. One explanation for these findings is that μ-beta ERD indexes early predictive coding (e.g....

A causal test of the motor theory of speech perception: A case of impaired speech production and spared speech perception

Stasenko, Alena; Bonn, Cory; Teghipco, Alex; Garcea, Frank E.; Sweet, Catherine; Dombovy, Mary; McDonough, Joyce; Mahon, Bradford Z.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/2015 EN
Relevância na Pesquisa
46.28%
In the last decade, the debate about the causal role of the motor system in speech perception has been reignited by demonstrations that motor processes are engaged during the processing of speech sounds. However, the exact role of the motor system in auditory speech processing remains elusive. Here we evaluate which aspects of auditory speech processing are affected, and which are not, in a stroke patient with dysfunction of the speech motor system. The patient’s spontaneous speech was marked by frequent phonological/articulatory errors, and those errors were caused, at least in part, by motor-level impairments with speech production. We found that the patient showed a normal phonemic categorical boundary when discriminating two nonwords that differ by a minimal pair (e.g., ADA-AGA). However, using the same stimuli, the patient was unable to identify or label the nonword stimuli (using a button-press response). A control task showed that he could identify speech sounds by speaker gender, ruling out a general labeling impairment. These data suggest that the identification (i.e. labeling) of nonword speech sounds may involve the speech motor system, but that the perception of speech sounds (i.e., discrimination) does not require the motor system. This means that motor processes are not causally involved in perception of the speech signal...

Gender and vocal production mode discrimination using the high frequencies for speech and singing

Monson, Brian B.; Lotto, Andrew J.; Story, Brad H.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
56.1%
Humans routinely produce acoustical energy at frequencies above 6 kHz during vocalization, but this frequency range is often not represented in communication devices and speech perception research. Recent advancements toward high-definition (HD) voice and extended bandwidth hearing aids have increased the interest in the high frequencies. The potential perceptual information provided by high-frequency energy (HFE) is not well characterized. We found that humans can accomplish tasks of gender discrimination and vocal production mode discrimination (speech vs. singing) when presented with acoustic stimuli containing only HFE at both amplified and normal levels. Performance in these tasks was robust in the presence of low-frequency masking noise. No substantial learning effect was observed. Listeners also were able to identify the sung and spoken text (excerpts from “The Star-Spangled Banner”) with very few exposures. These results add to the increasing evidence that the high frequencies provide at least redundant information about the vocal signal, suggesting that its representation in communication devices (e.g., cell phones, hearing aids, and cochlear implants) and speech/voice synthesizers could improve these devices and benefit normal-hearing and hearing-impaired listeners.

6.542J / 24.966J / HST.712J Laboratory on the Physiology, Acoustics, and Perception of Speech, Fall 2001; Laboratory on the Physiology, Acoustics, and Perception of Speech

Stevens, Kenneth N., 1924-; Perkell, Joseph S.; Shattuck, Stefanie Rumrill; Hanson, Helen M.; Slifka, Janet Louise Khoenle, 1964-
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 17365 bytes; 23942 bytes; 17210 bytes; 24164 bytes; 14498 bytes; 17090 bytes; 35981 bytes; 19898 bytes; 17068 bytes; 17368 bytes; 16993 bytes; 18007 bytes; 17565 bytes; 16832 bytes; 17399 bytes; 17046 bytes; 19297 bytes; 19421 bytes; 17178 bytes; 18295 by
EN-US
Relevância na Pesquisa
56.19%
Experimental investigations of speech processes. Topics: measurement of articulatory movements; measurements of pressures and airflows in speech production; computer-aided waveform analysis and spectral analysis of speech; synthesis of speech; perception and discrimination of speechlike sounds; speech prosody; models for speech recognition; speech disorders; and other topics. Recommended prerequisites: 6.002 or 18.03. Alternate years.

Relationships among speech perception, production, language, hearing loss, and age in children with impaired hearing

Blamey, P.; Sarant, J.; Paatsch, L.; Barry, J.; Bow, C.; Wales, R.; Wright, M.; Psarros, C.; Rattigan, K.; Tooher, R.
Fonte: Amer Speech-Language-Hearing Assoc Publicador: Amer Speech-Language-Hearing Assoc
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
66.35%
Eighty-seven primary-school children with impaired hearing were evaluated using speech perception, production, and language measures over a 3-year period. Forty-seven children with a mean unaided pure-tone-average hearing loss of 106 dB HL used a 22-electrode cochlear implant, and 40 with a mean unaided puretone-average hearing loss of 78 dB HL were fitted with hearing aids. All children were enrolled in oral/aural habilitation programs, and most attended integrated classes with normally hearing children for part of the time at school. Multiple linear regression was used to describe the relationships among the speech perception, production, and language measures, and the trends over time. Little difference in the level of performance and trends was found for the two groups of children, so the perceptual effect of the implant is equivalent, on average, to an improvement of about 28 dB in hearing thresholds. Scores on the Peabody Picture Vocabulary Test (PPVT) and the Clinical Evaluation of Language Fundamentals showed an upward trend at about 60% of the rate for normally hearing children. Rates of improvement for individual children were not correlated significantly with degree of hearing loss. The children showed a wide scatter about the average speech production score of 40% of words correctly produced in spontaneous conversations...

Activity in regions sensitive to auditory speech is modified during speech production: fMRI evidence for an efference copy

Zheng, Zhuo
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 3696523 bytes; application/pdf
EN; EN
Relevância na Pesquisa
56.12%
Models of speech production postulate that, in order to facilitate rapid and precise control of articulation, the predicted auditory feedback is sent to the auditory system to be compared with incoming sensory data. If this is so, an 'error' signal may be observed when the predicted auditory feedback and the sensory consequences of vocalization do not match. I used event-related fMRI to look for the neural concomitants of such an error signal. In two conditions volunteers whispered 'ted'. In one of these, voice-gated noise implemented in our real-time processing system was used to mask the auditory feedback, which should result in an error signal. Two other conditions were yoked to the production conditions (either clearly heard or masked), but were listen-only and therefore no error signal would be expected. I acquired whole-brain EPI data from 21 subjects using a fast-sparse design. Activity in the superior temporal gyrus bilaterally was significantly greater for clear than masked speech during the listen-only trials (F(1,20)≥12.84, p<0.002), and significantly higher for masked than for clear speech in the production trials (F(1,20)≥6.68, p<0.02). This crossover interaction indicates that speech production results in corollary discharge in the auditory system and furthermore suggests that this corollary discharge reflects expectations about the sensory concomitants of speech acts.; Thesis (Master...

Perceptual processing of auditory feedback during speech production and its neural substrates

Zheng, Zane
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
56.31%
One enduring question in the study of speech concerns the nature of the link between speech perception and production. Although accumulating evidence suggests that these two facets of spoken language are tightly coupled, the cognitive structure and neural organization underlying the interactions between the two processes are not well understood. In this thesis, I focus on questions that arise from observations related to when individuals are both talking and listening, and assess the sensitivity of talkers and listeners to the same change in the acoustics of speech. First, I aim to elucidate the neural substrates of auditory feedback control during vocalization by examining the brain response to acoustic perturbations towards auditory concomitants of speech using functional magnetic resonance imaging (fMRI) (Chapters 2 and 3). I demonstrate, for the first time, an extensive network of brain regions involved in the detection and correction of auditory feedback errors during speech production, for which three functionally differentiated neural systems can be delineated. Then I set out to address the online perception of own voice identity as individuals are talking. Chapters 4 and 5 measure the perceptual sensitivity of individuals to the auditory concomitants of their own speech by presenting temporally gated auditory feedback in stranger’s voices during talking. The results show that people perceive stranger’s voices as a modified version of their own voice and adjust their vocal production accordingly...

Integrando produção e percepção de proeminencias secundarias numa abordagem dinamica do ritmo da fala; Integrating production and perception of secundary prominences in a dynamical perspective of rhythm

Pablo Arantes
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 04/02/2010 PT
Relevância na Pesquisa
46.26%
Nesta tese são investigados dois temas: o acento secundário em português brasileiro e a integração entre a produção e a percepção do ritmo. Os dois temas são desenvolvidos tendo como pano de fundo o modelo dinâmico de produção do ritmo da fala de Barbosa (2006 e 2007). O fenômeno descrito como acento secundário é associado à ocorrência de proeminências na cadeia de sílabas pré-tônicas em palavras polissilábicas. O interesse pelo assunto decorre das disputas existentes na literatura sobre a natureza (e mesmo existência) destes acentos e os princípios que determinam sua distribuição e, ainda, da limitada quantidade disponível de dados experimentais para resolver essas disputas. Foram realizados dois experimentos de produção com o objetivo de descrever, em palavras polissilábicas com mais de duas pré-tônicas, os padrões apresentados por diversos parâmetros acústicos que são tradicionalmente associados à expressão do acento. Nos corpora dos experimentos foram manipuladas, entre outras variáveis, o tamanho da cadeia de pré-tônicas, a posição sintática e o status referencial das palavras-chave. Os parâmetros acústicos investigados foram duração, frequência fundamental, qualidade vocálica e ênfase espectral. Os resultados sugerem que há evidência para a manifestação de uma proeminência nas posições iniciais da cadeia de pré-tônicas. Essa proeminência...

Speech monitoring and phonologically-mediated eye gaze in language perception and production: a comparison using printed word eye-tracking

Gauvin, Hanna S.; Hartsuiker, Robert J.; Huettig, Falk
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 10/12/2013 EN
Relevância na Pesquisa
46.36%
The Perceptual Loop Theory of speech monitoring assumes that speakers routinely inspect their inner speech. In contrast, Huettig and Hartsuiker (2010) observed that listening to one's own speech during language production drives eye-movements to phonologically related printed words with a similar time-course as listening to someone else's speech does in speech perception experiments. This suggests that speakers use their speech perception system to listen to their own overt speech, but not to their inner speech. However, a direct comparison between production and perception with the same stimuli and participants is lacking so far. The current printed word eye-tracking experiment therefore used a within-subjects design, combining production and perception. Displays showed four words, of which one, the target, either had to be named or was presented auditorily. Accompanying words were phonologically related, semantically related, or unrelated to the target. There were small increases in looks to phonological competitors with a similar time-course in both production and perception. Phonological effects in perception however lasted longer and had a much larger magnitude. We conjecture that this difference is related to a difference in predictability of one's own and someone else's speech...

The developmental trajectory of children's perception and production of English /r/-/l/a)

Idemaru, Kaori; Holt, Lori L.
Fonte: Acoustical Society of America Publicador: Acoustical Society of America
Tipo: Artigo de Revista Científica
Publicado em /06/2013 EN
Relevância na Pesquisa
55.98%
The English /l-r/ distinction is difficult to learn for some second language learners as well as for native-speaking children. This study examines the use of the second (F2) and third (F3) formants in the production and perception of /l/ and /r/ sounds in 4-, 4.5-, 5.5-, and 8.5-yr-old English-speaking children. The children were tested with elicitation and repetition tasks as well as word recognition tasks. The results indicate that whereas young children's /l/ and /r/ in both production and perception show fairly high accuracy and were well defined along the primary acoustic parameter that differentiates them, F3 frequency, these children were still developing in regard to the integration of the secondary cue, F2 frequency. The pattern of development is consistent with the distribution of these features in the ambient input relative to the /l/ and /r/ category distinction: F3 is robust and reliable, whereas F2 is less reliable in distinguishing /l/ and /r/. With delayed development of F2, cue weighting of F3 and F2 for the English /l-r/ categorization seems to continue to develop beyond 8 or 9 yr of age. These data are consistent with a rather long trajectory of phonetic development whereby native categories are refined and tuned well into childhood.

Speech Perception and Production by Sequential Bilingual Children: A Longitudinal Study of Voice Onset Time Acquisition

McCarthy, Kathleen M; Mahon, Merle; Rosen, Stuart; Evans, Bronwen G
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.06%
The majority of bilingual speech research has focused on simultaneous bilinguals. Yet, in immigrant communities, children are often initially exposed to their family language (L1), before becoming gradually immersed in the host country's language (L2). This is typically referred to as sequential bilingualism. Using a longitudinal design, this study explored the perception and production of the English voicing contrast in 55 children (40 Sylheti-English sequential bilinguals and 15 English monolinguals). Children were tested twice: when they were in nursery (52-month-olds) and 1 year later. Sequential bilinguals' perception and production of English plosives were initially driven by their experience with their L1, but after starting school, changed to match that of their monolingual peers.

Auditory cortical deactivation during speech production and following speech perception: an EEG investigation of the temporal dynamics of the auditory alpha rhythm

Jenson, David; Harkrider, Ashley W.; Thornton, David; Bowers, Andrew L.; Saltuklaroglu, Tim
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 08/10/2015 EN
Relevância na Pesquisa
56.33%
Sensorimotor integration (SMI) across the dorsal stream enables online monitoring of speech. Jenson et al. (2014) used independent component analysis (ICA) and event related spectral perturbation (ERSP) analysis of electroencephalography (EEG) data to describe anterior sensorimotor (e.g., premotor cortex, PMC) activity during speech perception and production. The purpose of the current study was to identify and temporally map neural activity from posterior (i.e., auditory) regions of the dorsal stream in the same tasks. Perception tasks required “active” discrimination of syllable pairs (/ba/ and /da/) in quiet and noisy conditions. Production conditions required overt production of syllable pairs and nouns. ICA performed on concatenated raw 68 channel EEG data from all tasks identified bilateral “auditory” alpha (α) components in 15 of 29 participants localized to pSTG (left) and pMTG (right). ERSP analyses were performed to reveal fluctuations in the spectral power of the α rhythm clusters across time. Production conditions were characterized by significant α event related synchronization (ERS; pFDR < 0.05) concurrent with EMG activity from speech production, consistent with speech-induced auditory inhibition. Discrimination conditions were also characterized by α ERS following stimulus offset. Auditory α ERS in all conditions temporally aligned with PMC activity reported in Jenson et al. (2014). These findings are indicative of speech-induced suppression of auditory regions...