Speech rhythm as naturally occurring and culturally transmitted behavioral patterns

First published: 09 September 2019Rhythm is fundamental to every motor activity. Neural and physiological mechanisms that underlie rhythmic cognition, in general, and rhythmic pattern generation, in particular, are evolutionarily ancient. As speech production is a kind of motor activity, investigating speech rhythm can provide insight into how general motor patterns have been adapted for more specific use in articulation and speech production. Studies on speech rhythm may further provide insight into the development of speech capacity in humans. As speech capacity is putatively a prerequisite for developing a language faculty, studies on speech rhythm may cast some light on the mystery of language evolution in the human genus. Hereby, we propose an approach to exploring speech rhythm as a window on speech emergence in ontogenesis and phylogenesis, as well as on diachronic linguistic changes.This research is supported by the Basque Government through the BERC2018–2021 programand by the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation SEV-2015- 0490 and through project RTI 2018-098317-B-I00 funded by AEI/FEDER

Cross-Linguistic Differences in Bilinguals’ Fundamental Frequency Ranges

Accepted December 13, 2016Purpose We investigated cross-linguistic differences in fundamental frequency range (FFR) in Welsh-English bilingual speech. This is the first study that reports gender-specific behavior in switching FFRs across languages in bilingual speech. Method FFR was conceptualized as a behavioral pattern using measures of span (range of fundamental frequency—in semitones—covered by the speaker's voice) and level (overall height of fundamental frequency maxima, minima, and means of speaker's voice) in each language. Results FFR measures were taken from recordings of 30 Welsh-English bilinguals (14 women and 16 men), who read 70 semantically matched sentences, 35 in each language. Comparisons were made within speakers across languages, separately in male and female speech. Language background and language use information was elicited for qualitative analysis of extralinguistic factors that might affect the FFR. Conclusions Cross-linguistic differences in FFR were found to be consistent across female bilinguals but random across male bilinguals. Most female bilinguals showed distinct FFRs for each language. Most male bilinguals, however, were found not to change their FFR when switching languages. Those who did change used different strategies than women when differentiating FFRs between languages. Detected cross-linguistic differences in FFR can be explained by sociocultural factors. Therefore, sociolinguistic factors are to be taken into account in any further study of language-specific pitch setting and cross-linguistic differences in FFR

The effect of speech rhythm and speaking rate on assessment of pronunciation in a second language

Published online: 24 April 2019The study explores the effect of deviations from native speech rhythm and rate norms on the assessement of pronunciation mastery of a second language (L2) when the native language of the learner is either rhythmically similar to or different from the target language. Using the concatenative speech synthesis technique, different versions of the same sentence were created in order to produce segmentally and intonationally identical utterances that differed only in rhythmic patterns and/or speaking rate. Speech rhythm and tempo patterns modeled those from the speech of French or German native learners of English at different proficiency levels. Native British English speakers rated the original sentences and the synthesized utterances for accentedness. The analysis shows that (a) differences in speech rhythm and speaking tempo influence the perception of accentedness; (b) idiosyncratic differences in speech rhythm and speech rate are sufficient to differentiate between the proficiency levels of L2 learners; (c) the relative salience of rhythm and rate on perceived accentedness in L2 speech is modulated by the native language of the learners; and (d) intonation facilitates the perception of finer differences in speech rhythm between otherwise identical utterances. These results emphasize the importance of prosodic timing patterns for the perception of speech delivered by L2 learners.L.P. was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) via Juan de la Cierva fellowship. M.O. was supported by the IKERBASQUE–Basque Foundation for Science. The research institution was supported through the “Severo Ochoa” Programme for Centres/Units of Excellence in R&D (SEV-2015-490)

Native Language Influence in the Segmentation of a Novel Language

Published online: 04 Apr 2016.A major problem in second language acquisition (SLA) is the segmentation of fluent speech in the target language, i.e., detecting the boundaries of phonological constituents like words and phrases in the speech stream. To this end, among a variety of cues, people extensively use prosody and statistical regularities. We examined the role of pitch, duration, and transitional probabilities (TPs) between adjacent syllables in the segmentation of a novel language by native speakers of German and compared their responses with the segmentation by the listeners with a phonologically different native language: Italian. We used an artificial language with different prosodic cues marking the boundaries of statistically defined words. In artificial-language learning experiments, we compared how Germans and Italians use prosodic and statistical cues for segmenting continuous speech. We show that native phonology modulates the processing of prosodic cues in novel languages. While native speakers of Italian interpret prosodic cues at both the word and the phrasal level, native speakers of German interpret them exclusively at the phrasal level. Phrasal prosody can facilitate the segmentation of a novel language when prosodic and statistical cues lead to the same segmentation solution. Word-level prosody does not necessarily facilitate segmentation, but it can disrupt it when statistical and prosodic cues lead to different segmentation solutions.The research leading to these results was supported by the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013)/ERC Grant Agreement Number 269502 (PASCAL), by the Alexander von Humboldt Foundation, Germany, and by the Basque Foundation of Science, Spain

The role of metacognition in recognition of the content of statistical learning

Published online: 31 August 2020Despite theoretical debate on the extent to which statistical learning is incidental or modulated by explicit instructions and conscious awareness of the content of statistical learning, no study has ever investigated the metacognition of statistical learning. We used an artificial language-learning paradigm and a segmentation task that required splitting a continuous stream of syllables into discrete recurrent constituents. During this task, statistical learning potentially produces knowledge of discrete constituents as well as about statistical regularities that are embodied in familiarization input. We measured metacognitive sensitivity and efficiency (using hierarchical Bayesian modelling to estimate metacognitive sensitivity and efficiency) to probe the role of conscious awareness in recognition of constituents extracted from the familiarization input and recognition of novel constituents embodying the same statistical regularities as these extracted constituents. Novel constituents are conceptualized to represent recognition of statistical structure rather than recognition of items retrieved from memory as whole constituents. We found that participants are equally sensitive to both types of learning products, yet subject them to varying degrees of conscious processing during the postfamiliarization recognition test. The data point to the contribution of conscious awareness to at least some types of statistical learning contentThis study was supported by the European Commission via H2020 Marie Skłodowska-Curie Actions (Grant Number DLV-792331), and Spanish Ministerio de Economía y Competitividad (Grant Number RTI2018-098317-B-I00). The research institute is supported by the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres/ Units of Excellence in Research and Development (SEV-2015-490)

The effect of regular rhythm on the perception of linguistic and non-linguistic auditory input

First published: 30 October 2020Regular distribution of auditory stimuli over time can facilitate perception and attention. However, such effects have to date only been observed in separate studies using either linguistic or non-linguistic materials. This has made it difficult to compare the effects of rhythmic regularity on attention across domains. The current study was designed to provide an explicit within-subject comparison of reaction times and accuracy in an auditory target-detection task using sequences of regularly and irregularly distributed syllables (linguistic material) and environmental sounds (nonlinguistic material). We explored how reaction times and accuracy were modulated by regular and irregular rhythms in a sound- (non-linguistic) and syllable-monitoring (linguistic) task performed by native Spanish speakers (N = 25). Surprisingly, we did not observe that regular rhythm exerted a facilitatory effect on reaction times or accuracy. Further exploratory analysis showed that targets that appear later in sequences of syllables and sounds are identified more quickly. In late targets, reaction times in stimuli with a regular rhythm were lower than in stimuli with irregular rhythm for linguistic material, but not for non-linguistic material. The difference in reaction times on stimuli with regular and irregular rhythm for late targets was also larger for linguistic than for non-linguistic material. This suggests a modulatory effect of rhythm on linguistic stimuli only once the percept of temporal isochrony has been established. We suggest that temporal isochrony modulates attention to linguistic more than to non-linguistic stimuli because the human auditory system is tuned to process speech. The results, however, need to be further tested in confirmatory studies.This research was supported by the Spanish State Research Agency through BCBL's Severo Ochoa excellence accreditation SEV-2015-0490

Neural bases of learning and recognition of statistical regularities

First published: 09 January 2020Statistical learning is a set of cognitive mechanisms allowing for extracting regularities from the environment and segmenting continuous sensory input into discrete units. The current study used functional magnetic resonance imaging (fMRI) (N = 25) in conjunction with an artificial language learning paradigm to provide new insight into the neural mechanisms of statistical learning, considering both the online process of extracting statistical regularities and the subsequent offline recognition of learned patterns. Notably, prior fMRI studies on statistical learning have not contrasted neural activation during the learning and recognition experimental phases. Here, we found that learning is supported by the superior temporal gyrus and the anterior cingulate gyrus, while subsequent recognition relied on the left inferior frontal gyrus. Besides, prior studies only assessed the brain response during the recognition of trained words relative to novel nonwords. Hence, a further key goal of this study was to understand how the brain supports recognition of discrete constituents from the continuous input versus recognition of mere statistical structure that is used to build new constituents that are statistically congruent with the ones from the input. Behaviorally, recognition performance indicated that statistically congruent novel tokens were less likely to be endorsed as parts of the familiar environment than discrete constituents. fMRI data showed that the left intraparietal sulcus and angular gyrus support the recognition of old discrete constituents relative to novel statistically congruent items, likely reflecting an additional contribution from memory representations for trained items.The research was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the “Severo Ochoa” Programme for Centres/Units of Excellence in R&D (SEV-2015- 490), and project Grant RTI2018-098317-B-I00 awarded to M.O., by the Basque Government through project Grant PI-2017-25 awarded to D.S., and by the European Commission as Marie Skłodowska-Curie Fellowship DLV-792331 to L.P

Metacognitive Processing in Language Learning Tasks Is Affected by Bilingualism

This article was published Online First July 8, 2019We assessed the effect of bilingualism on metacognitive processing in the artificial language learning task, in 2 experiments varying in the difficulty to segment the language. Following a study phase in which participants were exposed to the artificial language, segmentation performance was assessed by means of a dual forced-choice recognition test followed by confidence judgments. We used a signal detection approach to estimate type 1 performance (i.e., the participants’ ability to discriminate statistical words vs. foils constructed from the same syllables) and type 2 metacognitive performance (i.e., the ability to discriminate the correctness of the type 1 decisions by confidence ratings). The results showed that bilinguals and monolinguals do not differ in type 1 recognition performance, but across the 2 experiments, metacognitive performance was higher in bilinguals compared with monolinguals. The results show that bilingualism improves metacognitive evaluation of performance in linguistic domains. We suggest that the improvement in metacognitive performance stems from bilinguals’ enhanced errormonitoring abilities in language domain, which is also modulated by individual experience.The research was supported by the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres/ Units of Excellence in Research and Development (SEV-2015-490) and project grants RTI2018-098317-B-I00 (to Mikhail Ordin) and the Basque Government grant PI-2017-25 (to David Soto). Leona Polyanskaya was supported by the European Commission with the Marie Skłodowska-Curie Research Fellowship

Relative Salience of Speech Rhythm and Speech Rate on Perceived Foreign Accent in a Second Language

We investigated the independent contribution of speech rate and speech rhythm to perceived foreign accent. To address this issue we used a resynthesis technique that allows neutralizing segmental and tonal idiosyncrasies between identical sentences produced by French learners of English at different proficiency levels and maintaining the idiosyncrasies pertaining to prosodic timing patterns. We created stimuli that (1) preserved the idiosyncrasies in speech rhythm while controlling for the differences in speech rate between the utterances; (2) preserved the idiosyncrasies in speech rate while controlling for the differences in speech rhythm between the utterances; and (3) preserved the idiosyncrasies both in speech rate and speech rhythm. All the stimuli were created in intoned (with imposed intonational contour) and flat (with monotonized, constant F0) conditions. The original and the resynthesized sentences were rated by native speakers of English for degree of foreign accent. We found that both speech rate and speech rhythm influence the degree of perceived foreign accent, but the effect of speech rhythm is larger than that of speech rate. We also found that intonation enhances the perception of fine differences in rhythmic patterns but reduces the perceptual salience of fine differences in speech rate

Electrophysiology of statistical learning: Exploring the online learning process and offline learning product

First published: 24 December 2019A continuous stream of syllables is segmented into discrete constituents based on the transitional probabilities (TPs) between adjacent syllables by means of statistical learning. However, we still do not know whether people attend to high TPs between frequently co-occurring syllables and cluster them together as parts of the discrete constituents or attend to low TPs aligned with the edges between the constituents and extract them as whole units. Earlier studies on TP-based segmentation also have not distinguished between the segmentation process (how people segment continuous speech) and the learning product (what is learnt by means of statistical learning mechanisms). In the current study, we explored the learning outcome separately from the learning process, focusing on three possible learning products: holistic constituents that are retrieved from memory during the recognition test, clusters of frequently co-occurring syllables, or a set of statistical regularities which can be used to reconstruct legitimate candidates for discrete constituents during the recognition test. Our data suggest that people employ boundary-finding mechanisms during online segmentation by attending to low inter-syllabic TPs during familiarization and also identify potential candidates for discrete constituents based on their statistical congruency with rules extracted during the learning process. Memory representations of recurrent constituents embedded in the continuous speech stream during familiarization facilitate subsequent recognition of these discrete constituents.Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: RTI2018-098317-B-I00 ; H2020 Marie Skłodowska-Curie Actions, Grant/Award Number: DLV-792331; Ekonomiaren Garapen eta Lehiakortasun Saila, Eusko Jaurlaritza, Grant/Award Number: PI-2017-25; Spanish Ministry of Economy and Competitiveness (MINECO) through the “Severo Ochoa” Programme for Centres/Units of Excellence in R&D, Grant/Award Number: SEV-2015-490; Basque Government, Grant/Award Number: PI-2017-25; European Commission through the Marie Skłodowska-Curie Research Fellowshi