Lexical access in Portuguese stress

Categorical approaches to lexical stress typically assume that words have either regular or irregular stress, and imply that only the latter needs to be stored in the lexicon, while the former can be derived by rule. In this paper, we compare these two groups of words in a lexical decision task in Portuguese to examine whether the dichotomy in question affects lexical retrieval latencies in native speakers, which could indirectly reveal different processing patterns. Our results show no statistically credible effect of stress regularity on reaction times, even when lexical frequency, neighborhood density, and phonotactic probability are taken into consideration. The lack of an effect is consistent with a probabilistic approach to stress, not with a categorical (traditional) approach where syllables are either light or heavy and stress is either regular or irregular. We show that the posterior distribution of credible effect sizes of regularity is almost entirely within the region of practical equivalence, which provides strong evidence that no effect of regularity exists in the lexical decision data modelled. Frequency and phonotactic probability, in contrast, showed statistically credible effects given the experimental data modelled, which is consistent with the literature

Perception and production of english final stops by young brazilian efl students

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras/Inglês e Literatura correspondenteThis research focuses on the investigation of the perception and production of English final-stops by young Brazilian EFL students. It was reported the quantitative results of one AX discrimination, one imitation and one free-production test. The discussion of the tendencies of production as well as the relationship between perception and production tested the hypothesis of markedness degree in relation to voicing and place of articulation of the target phonemes. In addition, the correlation between the perceptual sensitivity of CVC syllable pattern and the ability to produce the final-stops in a target-like fashion was also analyzed in the present study. Twelve learners (mean age 5.2 years) in their 4 ½ semesters of L2 instruction were tested. Following Koerich (2002), the six stops were investigated in terms of markedness of the consonants by: (1) voicing of the final-stops, and (2) place of articulation. In addition, it was examined the markedness of the CVC syllabic pattern and the simplification strategies applied by this sample. The relationship between perception and production was assessed in terms of syllabic complexity (CVC versus CVCi). The overall results revealed that the participants do apply simplification strategies to final-stops in CVC words. The voiced stops were not more mispronounced than the voiceless targets and the bilabials seemed to be the only ones that, if not modified by epenthesis, followed the prediction concerning place of articulation. A positive correlation was found between the results from the imitation and the production tests, and not from the AX discrimination results. Esta pesquisa tem o objetivo de investigar a percepção e a produção das obstruintes finais em palavras do inglês por crianças falantes do Português. Resultados quantitativos dos testes de percepção (AX), de imitação e de produção foram reportados conjuntamente com discussão sobre as tendências na produção e na relação entre produção e percepção, testando a hipótese da marcação em relação a vozeamento e ao ponto articulatório das consoantes-alvo, assim como a da correlação entre a percepção do padrão silábico CVC e a habilidade de produzir as obstruintes apropriadamente. Doze estudantes (M = 5 anos e 2 meses) em seu 4? semestre de instrução foram testados. Seguindo Koerich, 2002, as obstruintes foram investigadas em duas variáveis relacionadas à marcação das consoantes: (1) vozeamento das obstruintes e (2) ponto articulatório. Foram examinadas as estratégias de simplificação utilizadas pela população testada em relação à marcação do padrão silábico CVC. A relação entre percepção e produção foi verificada de acordo com o contraste entre CVC e CVCi. Os resultados revelaram que os participantes fizeram uso de estratégias de simplificação nas obstruintes finais. As obstruintes vozeadas não mostraram mais erros de pronúncia do que as surdas e as labiais foram as únicas que, quando não receberam a vogal epentética, seguiram a tendência em relação ao ponto articulatório. Foi verificada uma fraca correlação positiva apenas entre os resultados obtidos no teste de imitação e produção

¿Qué es la fonología computacional?

Computational phonology is not one thing. Rather, it is an umbrella term which may refer to work on formal language theory, computer-implemented models of cognitive processes, and corpus methods derived from the literature on natural language processing (NLP). This article gives an overview of these distinct areas, identifying commonalities and differences in the goals of each area, as well as highlighting recent results of interest. The overview is necessarily brief and subjective. Broadly speaking, it is argued that learning is a pervasive theme in these areas, but the core questions and concerns vary too much to define a coherent field. Computational phonologists are more united by a shared body of formal knowledge than they are by a shared sense of what the important questions are.La fonología computacional no representa un campo unitario, sino que es un término genérico que puede hacer referencia a obras sobre teorías de lenguajes formales; a modelos de procesos cognitivos implementados por ordenador; y a métodos de trabajo con corpus, derivados de la bibliografía sobre procesamiento del lenguaje natural (PLN). Este artículo ofrece una visión de conjunto de estas distintas áreas, identifica los puntos comunes y las diferencias en los objetivos de cada una, y pone de relieve algunos de los últimos resultados más relevantes. Esta visión de conjunto es necesariamente breve y subjetiva. En términos generales, se argumenta que el aprendizaje es un tema recurrente en estos ámbitos, pero las preguntas y los problemas centrales varían demasiado como para definir un área de estudio unitaria y coherente. Los fonólogos computacionales están unidos por un cúmulo común de conocimientos formales más que por un parecer compartido acerca de cuáles son las preguntas importantes

Continuous-speech segmentation at the beginning of language acquisition: Electrophysiological evidence

Word segmentation, or detecting word boundaries in continuous speech, is not an easy task. Spoken language does not contain silences to indicate word boundaries and words partly overlap due to coarticalution. Still, adults listening to their native language perceive speech as individual words. They are able to combine different distributional cues in the language, such as the statistical distribution of sounds and metrical cues, with lexical information, to efficiently detect word boundaries. Infants in the first year of life do not command these cues. However, already between seven and ten months of age, before they know word meaning, infants learn to segment words from speech. This important step in language acquisition is the topic of this dissertation. In chapter 2, the first Event Related Brain Potential (ERP) study on word segmentation in Dutch ten-month-olds is discussed. The results show that ten-month-olds can already segment words with a strong-weak stress pattern from speech and they need roughly the first half of a word to do so. Chapter 3 deals with segmentation of words beginning with a weak syllable, as a considerable number of words in Dutch do not follow the predominant strong-weak stress pattern. The results show that ten-month-olds still largely rely on the strong syllable in the language, and do not show an ERP response to the initial weak syllable. In chapter 4, seven-month-old infants' segmentation of strong-weak words was studied. An ERP response was found to strong-weak words presented in sentences. However, a behavioral response was not found in an additional Headturn Preference Procedure study. There results suggest that the ERP response is a precursor to the behavioral response that infants show at a later age

Knowledge Modelling and Learning through Cognitive Networks

One of the most promising developments in modelling knowledge is cognitive network science, which aims to investigate cognitive phenomena driven by the networked, associative organization of knowledge. For example, investigating the structure of semantic memory via semantic networks has illuminated how memory recall patterns influence phenomena such as creativity, memory search, learning, and more generally, knowledge acquisition, exploration, and exploitation. In parallel, neural network models for artificial intelligence (AI) are also becoming more widespread as inferential models for understanding which features drive language-related phenomena such as meaning reconstruction, stance detection, and emotional profiling. Whereas cognitive networks map explicitly which entities engage in associative relationships, neural networks perform an implicit mapping of correlations in cognitive data as weights, obtained after training over labelled data and whose interpretation is not immediately evident to the experimenter. This book aims to bring together quantitative, innovative research that focuses on modelling knowledge through cognitive and neural networks to gain insight into mechanisms driving cognitive processes related to knowledge structuring, exploration, and learning. The book comprises a variety of publication types, including reviews and theoretical papers, empirical research, computational modelling, and big data analysis. All papers here share a commonality: they demonstrate how the application of network science and AI can extend and broaden cognitive science in ways that traditional approaches cannot

Crosslinguistic influence in third language acquisition

In this dissertation, crosslinguistic influence in third language (L3) acquisition is investigated in three articles that explore how linguistic variables affect the influence of pre-existing grammars. The goal is to contribute to novel insights about the cognitive process of language acquisition. We collected data in offline acceptability judgements tasks. In articles 1 and 2, we tested Norwegian–English bilinguals who were exposed to an artificial L3. In article 3, we tested Russian–Norwegian bilinguals who had been instructed in English for five–six years. We analysed the data by means of mixed-effects modelling. The results show that L3ers are influenced by both pre-existing languages, at early and intermediate stages. At intermediate stages, we documented both facilitative and non-facilitative influence. We clearly see that the source of the influence is affected by similarities between the L3 and pre-existing grammars, but we find no indications of wholesale transfer. We argue that the results reflect a complex learning situation in which candidate structures from both pre-existing languages are co-activated and compete for the overall best fit to the L3 input. The goodness of fit of a given structure determines the level of activation and consequently, the influence on the target interlanguage.I denne avhandlingen utforsker vi tverrspråklig innflytelse i tredjespråkstilegnelse gjennom tre artikler som undersøker hvordan ulike lingvistiske variabler påvirker innflytelsen av tidligere tilegnede språksystemer. Målet med avhandlingen er å bidra til ny innsikt i språktilegnelse som kognitiv prosess. Vi samlet data ved hjelp av offline akseptabilitetstester. I artikkel 1 og 2 testet vi norsk–engelsk tospråklige som ble eksponert for et kunstig tredjespråk. I artikkel 3 testet vi tospråklige talere av russisk og norsk som hadde hatt engelsk på skolen i fem–seks år. Vi brukte regresjonsanalyse (blandet modell) til å utforske dataene. Resultatene viser at begge tidligere tilegnede språk påvirker tredjespråket, både tidlig i tilegnelsesprosessen og ved senere stadier. Blant mer erfarne tredjespråksinnlærere finner vi både positiv og negativ innflytelse. Vi finner ingen indikasjoner på at et av språkene blir valgt som den eneste kilden til tverrspråklig innflytelse, men derimot at likheter mellom målspråkets grammatikk og tidligere tilegnede grammatiske systemer påvirker hvor innflytelsen kommer fra. Vi argumenterer for at resultatene reflekterer en kompleks læringssituasjon der lingvistiske strukturer fra begge tidligere tilegnede språk er parallelt aktivert og kjemper mot hverandre i en konkurranse der likheter mellom målspråket og de eksisterende språkene i stor grad avgjør innflytelsen på tredjespråket

Phonological awareness and pronunciation in a second language

[spa] El propósito de esta tesis es incrementar el conocimiento de la consciencia fonológica en L2 a través de tres objetivos: estudiar la naturaleza de la consciencia fonológica en L2 y su relación con diferencias individuales, examinar la relación entre la consciencia fonológica y la pronunciación en L2, y desarrollar instrumentos para medir eficazmente consciencia fonológica en L2. La investigación previa sobre consciencia fonológica se ha centrado en la adquisición literaria de Ll. En el ámbito de SLA, consciencia fonológica ha sido examinada en su dimensión explícita. No obstante, aprendices de L2 rara vez son capaces de explicar aspectos de la pronunciación. En consecuencia, el presente estudio postula que la consciencia fonológica en L2 consiste mayoritariamente de conocimiento procedimental. Testamos la consciencia fonológica en L2 de 71 aprendices brasileños del inglés a través de tres tests específicos (fonémico, prosódico y fonotáctico). El rendimiento en estos tests fue relacionado con la pronunciación en L2 (medida como el grado de acento extranjero) y con experiencia y uso de L2 y competencia lingüística en L2. Además, 19 hablantes nativos de inglés realizaron los mismos tests de consciencia fonológica, posibilitando la comparativa de consciencia fonológica entre Ll y L2. Los resultados revelaron que los aprendices de L2 manifestaron un grado de consciencia fonológica significativamente menor que los hablantes nativos. Además, la consciencia fonológica en L2 explicó 32.8% de la varianza en la pronunciación en L2. Con respecto a las diferencias individuales, la competencia lingüística en L2 explicó variación única en consciencia fonológica en L2, mientras que el rol de la experiencia y uso de L2 resultaron inconclusos. Aparte de contribuir al conocimiento de la naturaleza de la consciencia fonológica en L2, los resultados tienen implicaciones pedagógicas importantes. El conocimiento de las lagunas en la consciencia fonológica de un aprendiz de L2 posibilita al profesor atraerlas hacia su atención, lo que podría reflejarse en la mejora de la pronunciación. Por último, se espera que los instrumentos desarrollados guíen futuros estudios en consciencia fonológica en L2.[eng] The objective of this dissertation is to increase knowledge about L2 phonological awareness through three research agendas: to investigate the nature of L2 phonological awareness in adult language learners and its relation to some individual differences, to examine the relationship between L2 phonological awareness and L2 pronunciation, and to create novel language-specific instruments to measure L2 phonological awareness reliably. Research on phonological awareness has focused on L1 literacy acquisition, where it has been understood as the ability to manipulate speech segments. In SLA, phonological awareness has been examined in its explicit dimension. Nevertheless, due to the special nature of L2 speech acquisition, L2 learners are rarely able to elaborate explicitly on aspects of pronunciation. Consequently, the present study advocates that L2 phonological awareness mainly consists of proceduralized knowledge. L1 BraziIian Portuguese learners of English (n=71) were tested on their awareness about the L2 phonological system through three domain-specific (segmental, suprasegmental and phonotactic) tasks. Performance in the L2 phonological awareness tasks was related to the participants' L2 pronunciation (measured with a Foreign Accent Rating Task) and to individual differences in the amount of L2 experience, L2 use and L2 proficiency. Additionally, 19 L1 American English speakers performed the same phonological awareness tasks, enabling comparison between L1 and L2 phonological awareness. The results revealed that L2 learners manifested significantly lower degrees of phonological awareness than L1 speakers. Moreover, L2 phonological awareness explained 32.8% of the variance in L2 pronunciation. As for the individual differences, L2 proficiency explained unique variance in L2 phonological awareness, whereas the role of L2 experience and use remained unsettled. Apart from contributing to our understanding of the nature of L2 phonological awareness, the findings of the present study have important pedagogical implications. Knowing the gaps in a language learner's L2 phonological awareness enables the instructor to bring them to the learner's attention, which in turn could be positively reflected in improved L2 pronunciation. Finally, the instruments developed for the present study are expected to guide further studies on L2 phonological awareness

Multi-dialect Arabic broadcast speech recognition

Dialectal Arabic speech research suffers from the lack of labelled resources and standardised orthography. There are three main challenges in dialectal Arabic speech recognition: (i) finding labelled dialectal Arabic speech data, (ii) training robust dialectal speech recognition models from limited labelled data and (iii) evaluating speech recognition for dialects with no orthographic rules. This thesis is concerned with the following three contributions: Arabic Dialect Identification: We are mainly dealing with Arabic speech without prior knowledge of the spoken dialect. Arabic dialects could be sufficiently diverse to the extent that one can argue that they are different languages rather than dialects of the same language. We have two contributions: First, we use crowdsourcing to annotate a multi-dialectal speech corpus collected from Al Jazeera TV channel. We obtained utterance level dialect labels for 57 hours of high-quality consisting of four major varieties of dialectal Arabic (DA), comprised of Egyptian, Levantine, Gulf or Arabic peninsula, North African or Moroccan from almost 1,000 hours. Second, we build an Arabic dialect identification (ADI) system. We explored two main groups of features, namely acoustic features and linguistic features. For the linguistic features, we look at a wide range of features, addressing words, characters and phonemes. With respect to acoustic features, we look at raw features such as mel-frequency cepstral coefficients combined with shifted delta cepstra (MFCC-SDC), bottleneck features and the i-vector as a latent variable. We studied both generative and discriminative classifiers, in addition to deep learning approaches, namely deep neural network (DNN) and convolutional neural network (CNN). In our work, we propose Arabic as a five class dialect challenge comprising of the previously mentioned four dialects as well as modern standard Arabic. Arabic Speech Recognition: We introduce our effort in building Arabic automatic speech recognition (ASR) and we create an open research community to advance it. This section has two main goals: First, creating a framework for Arabic ASR that is publicly available for research. We address our effort in building two multi-genre broadcast (MGB) challenges. MGB-2 focuses on broadcast news using more than 1,200 hours of speech and 130M words of text collected from the broadcast domain. MGB-3, however, focuses on dialectal multi-genre data with limited non-orthographic speech collected from YouTube, with special attention paid to transfer learning. Second, building a robust Arabic ASR system and reporting a competitive word error rate (WER) to use it as a potential benchmark to advance the state of the art in Arabic ASR. Our overall system is a combination of five acoustic models (AM): unidirectional long short term memory (LSTM), bidirectional LSTM (BLSTM), time delay neural network (TDNN), TDNN layers along with LSTM layers (TDNN-LSTM) and finally TDNN layers followed by BLSTM layers (TDNN-BLSTM). The AM is trained using purely sequence trained neural networks lattice-free maximum mutual information (LFMMI). The generated lattices are rescored using a four-gram language model (LM) and a recurrent neural network with maximum entropy (RNNME) LM. Our official WER is 13%, which has the lowest WER reported on this task. Evaluation: The third part of the thesis addresses our effort in evaluating dialectal speech with no orthographic rules. Our methods learn from multiple transcribers and align the speech hypothesis to overcome the non-orthographic aspects. Our multi-reference WER (MR-WER) approach is similar to the BLEU score used in machine translation (MT). We have also automated this process by learning different spelling variants from Twitter data. We mine automatically from a huge collection of tweets in an unsupervised fashion to build more than 11M n-to-m lexical pairs, and we propose a new evaluation metric: dialectal WER (WERd). Finally, we tried to estimate the word error rate (e-WER) with no reference transcription using decoding and language features. We show that our word error rate estimation is robust for many scenarios with and without the decoding features