Counteracting age related effects in L2 acquisition : training to distinguish between French vowels

Two key methods of perceptually training difficult L2 contrasts are the perceptual fading (PF) technique and the high variability phonetic training (HVPT) technique, and perceptual benefits from using both of these methods have also been found to transfer to pronunciation. However, these techniques have not been compared in their classic forms (PF with one speaker vs. HVPT with multiple speakers) with regard to perceptual gains, nor have they been compared with regard to gains in pronunciation accuracy or how any improvement is retained in the long term. Furthermore, whilst a number of studies suggest that motivation, the concern for L2 pronunciation accuracy aspect in particular, along with perception and/or pronunciation training may contribute to more nativelike pronunciation in late L2 learners, this has not been examined with specific reference to these training techniques. The present work compares these techniques for training native English speaking learners of French on difficult L2 French contrasts (/u/ vs. /y/ and /ɑ˜/vs./ɔ˜/),and assesses participant concern for pronunciation accuracy in order to ascertain an optimal training technique to improve the perception and pronunciation of less able learners. Experiment 1 of this thesis compares HVPT and PF using multiple and single speakers and found that the single speaker HVPT technique was significantly less effective than the others immediately after training. Testing again after at least one month suggested that training was best retained either through using PF with one speaker or HVPT with multiple speakers, that is, the techniques in their classic forms. Experiment 2 examines the benefits of these perceptual training techniques vs. pronunciation training vs. perception AND pronunciation training for both perceptual and pronunciation improvement. Undergoing multiple speaker HVPT + pronunciation training (over the same timescale as training in a single modality) appeared to be most beneficial for perception and pronunciation. Experiment 3 examines the relationship between average pronunciation improvement and participant concern for pronunciation accuracy as measured Elliott’s (1995) Pronunciation Attitude Inventory and found that a high concern for pronunciation accuracy is only related to greater improvements when specific, perhaps more monotonous, training techniques (using only one modality and speaker) are used. Overall, the present results provided no evidence of transfer of perceptual training benefits to pronunciation, and only slight evidence of transfer of pronunciation training benefits to perception, although there was a clear link between participant perception and pronunciation ability before training commenced. This is likely to be at least partly why some training in both modalities emerged as most successful in terms of improvements in both domains. It was therefore suggested that it may be prudent to consider the relationship between perceptual and production learning as distinct from any links between perception and production in general

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

Doctoral Dissertation in Language Sciences Specialization in English LinguisticsSeveral 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, 1995). Experimental studies that investigated the effects of perceptual training on non-native speech sound perception and production reported its success not only in the modification of adult learners’ perceptual patterns, but also in the improvement of their pronunciation accuracy, confirming, thereby, the plasticity of L2/FL learners’ mature perceptual system (e.g., Aliaga-Garcia, 2013; Pereira & Hazan, 2013; Wang, 2008; Wang et al., 2003). Difficulties in the perception of non-native vowel contrasts have been widely described as a significant part of the problems learners have in L2/FL phonological acquisition/learning (Strange, 2007). Therefore, the present study investigated the effects of perceptual training on the learning of three English contrasts (/i/-/ɪ/; /ɛ/-/æ/; /u/-/ʊ/) by a group of EFL (English as a Foreign Language) learners. This set of vowel contrasts was selected due to reported difficulties European Portuguese native speakers have in perceiving and producing them (Flege, 1994, as cited in Flege, 1995; Rato et al., 2013). The English phonological categories /ɪ/, /æ/ and /ʊ/ tend to be assimilated to the Portuguese vowel sounds /i/, /ɛ/ and /u/, respectively, and no distinction between the two vowels of each pair is made, due to their acoustic and articulatory proximity. Specifically, this study investigated (i) whether a high variability perceptual training, which included stimuli with different phonemic contexts produced by multiple native talkers, had a positive effect on the perception of the English target segments; (ii) if transfer of improvement to oral production was observed; (iii) whether perceptual learning generalized to identification of new words produced by novel talkers; and (iv) if long-term training effects remained. The participants’ perception was assessed three times with an identification test designed with natural stimuli: (1) before the auditory training – pretest; (2) immediately after the training was over – posttest; and (3) two months later – delayed posttest. The perceptual training program consisted of five sessions divided into two blocks, which included discrimination tasks and identification sequences followed by immediate feedback. Production was tested simultaneously in the three phases by means of a sentence-reading task with the target vowel segments. The results show that the Portuguese learners’ performance in the identification of the English vowels improved significantly, and perceptual gains were retained two months after completion of the training sessions. Moreover, the results of the generalization test indicate that there was robust learning of the two front vowel pairs. Acoustic analyses of spoken data revealed that phonological learning transferred to production. In sum, these results support the claim that perceptual learning can occur in a formal non-naturalistic environment within a short period of time and corroborate previous findings on the malleability of L2/FL adult learners’ perceptual systems.Vários estudos têm demonstrado que, na aprendizagem de uma língua não materna (LNM), a perceção e a produção de determinados contrastes fonológicos e fonéticos não nativos são um desafio para aprendentes tardios (adolescentes ou adultos) (Moyer, 2013). Diversos fatores podem explicar essas dificuldades, tais como a idade do início da aprendizagem, a frequência de uso, a quantidade e a qualidade de exposição à LNM e a influência do sistema fonológico da língua materna (L1) (Piske, 2007). O Speech Learning Model (SLM), desenvolvido por Flege (1995), explica que as dificuldades percetivas e, consequentemente, produtivas se devem ao facto de o sistema de sons linguísticos da L1 impedir a formação de novas categorias fonológicas para a segunda língua ou língua estrangeira (L2/LE). No entanto, um número considerável de estudos tem revelado que aprendentes tardios podem aprender a perceber e a produzir contrastes segmentais e suprassegmentais não nativos, uma vez que os mecanismos usados para aprender o sistema de sons da L1 são ativados na aprendizagem de uma LNM e permanecem intactos durante toda a vida (Flege, 1995). Estes estudos empíricos, que investigaram os efeitos do treino percetivo na perceção e produção de sons não nativos, reportaram a sua eficácia não somente na modificação de padrões percetivos, mas também na melhoria da capacidade produtiva dos mesmos, confirmando assim a plasticidade do sistema percetivo dos aprendentes de LNMs (por exemplo, Aliaga- Garcia, 2013; Pereira & Hazan, 2013; Wang, 2008; Wang et al., 2003). Os resultados de extensa investigação indicam que as dificuldades na perceção de contrastes vocálicos não nativos são uma parte significativa dos problemas que os aprendentes revelam na aquisição/aprendizagem fonológica de uma L2/LE (Strange, 2007). Portanto, no presente estudo, investigaram-se os efeitos do treino percetivo na aprendizagem de três contrastes vocálicos da língua inglesa (/i/-/ɪ/; /ɛ/-/æ/; /u/-/ʊ/) por um grupo de aprendentes de inglês como LE. Estes três contrastes foram escolhidos devido às dificuldades percetivas e produtivas que falantes nativos de português europeu revelam na sua aprendizagem (Flege, 1994, citado em Flege, 1995; Rato et al., 2013). As categorias fonológicas /ɪ/, /æ/ e /ʊ/ da L2/LE tendem a ser assimiladas como sons da L1, /i/, /ɛ/ e /u/, respetivamente, não se verificando qualquer distinção entre as vogais dos três contrastes, devido à sua proximidade acústica e articulatória. Especificamente, pretendeu-se (i) observar o efeito de um treino percetivo de alta variabilidade, que incluiu estímulos produzidos por vários locutores nativos em diferentes contextos fonológicos, na melhoria da capacidade percetiva dos segmentos-alvo; (ii) averiguar a transferência da melhoria para a produção oral; (iii) verificar a generalização para novos contextos e novos falantes; e (iv) analisar os efeitos do treino a longo prazo. A perceção dos participantes foi testada três vezes com uma tarefa auditiva de identificação com estímulos naturais: (1) antes do treino – pré-teste; (2) imediatamente depois do treino – pós-teste; e (3) dois meses mais tarde – teste de retenção. O programa de treino consistiu em cinco sessões, divididas em dois blocos, que incluíram tarefas de identificação e de discriminação auditivas seguidas de correção imediata. A produção foi testada, igualmente, em três fases, através da leitura de frases veículo, contendo palavras com os segmentos vocálicos. Os resultados demonstram que os aprendentes portugueses melhoraram significativamente na identificação das vogais-alvo e essa melhoria da sua competência percetiva manteve-se dois meses após o término do treino. Para além disso, os resultados do teste de generalização indicam que houve uma aprendizagem robusta dos dois contrastes vocálicos anteriores. As análises acústicas das produções dos informantes revelaram também uma transferência da aprendizagem para a produção oral. Estes resultados suportam a afirmação de que a aprendizagem ao nível da perceção de fala pode ocorrer em contextos formais, num curto período de tempo, e corroboram resultados anteriores sobre a maleabilidade dos sistemas percetuais fonológicos de aprendentes adultos de uma LNM