Publications

Abstract

Acquiring a second language (L2) requires newly learned information to be integrated with existing knowledge. It has been proposed that several memory systems work together to enable this process of rapidly encoding new information and then slowly incorporating it with existing knowledge, such that it is consolidated and integrated into the language network without catastrophic interference. This chapter focuses on consolidation of L2 vocabulary. First, the complementary learning systems model is outlined, along with the model’s predictions regarding lexical consolidation. Next, word learning studies in first language (L1) that investigate the factors playing a role in consolidation, and the neural mechanisms underlying this, are reviewed. Using the L1 memory consolidation literature as background, the chapter then presents what is currently known about memory consolidation in L2 word learning. Finally, considering what is already known about L1 but not about L2, future research investigating memory consolidation in L2 neurocognition is proposed.

Abstract

During listening, brain activity tracks the rhythmic structures of speech signals. Here, we directly dissociated the contribution of neural envelope tracking in the processing of speech acoustic cues from that related to linguistic processing. We examined the neural changes associated with the comprehension of Noise-Vocoded (NV) speech using magnetoencephalography (MEG). Participants listened to NV sentences in a 3-phase training paradigm: (1) pre-training, where NV stimuli were barely comprehended, (2) training with exposure of the original clear version of speech stimulus, and (3) post-training, where the same stimuli gained intelligibility from the training phase. Using this paradigm, we tested if the neural responses of a speech signal was modulated by its intelligibility without any change in its acoustic structure. To test the influence of spectral degradation on neural envelope tracking independently of training, participants listened to two types of NV sentences (4-band and 2-band NV speech), but were only trained to understand 4-band NV speech. Significant changes in neural tracking were observed in the delta range in relation to the acoustic degradation of speech. However, we failed to find a direct effect of intelligibility on the neural tracking of speech envelope in both theta and delta ranges, in both auditory regions-of-interest and whole-brain sensor-space analyses. This suggests that acoustics greatly influence the neural tracking response to speech envelope, and that caution needs to be taken when choosing the control signals for speech-brain tracking analyses, considering that a slight change in acoustic parameters can have strong effects on the neural tracking response.

Abstract

Luthra, Peraza-Santiago, Beeson, Saltzman, Crinnion, and Magnuson (2021) present data from the lexically mediated compensation for coarticulation paradigm that they claim provides conclusive evidence in favor of top-down processing in speech perception. We argue here that this evidence does not support that conclusion. The findings are open to alternative explanations, and we give data in support of one of them (that there is an acoustic confound in the materials). Lexically mediated compensation for coarticulation thus remains elusive, while prior data from the paradigm instead challenge the idea that there is top-down processing in online speech recognition.

Abstract

While recent laboratory studies suggest that the use of competing languages is a driving force in foreign language (FL) attrition (i.e. forgetting), research on “real” attriters has failed to demonstrate
such a relationship. We addressed this issue in a large-scale longitudinal study, following German students throughout a study abroad in Spain and their first six months back in Germany. Monthly,
percentage-based frequency of use measures enabled a fine-grained description of language use.
L3 Spanish forgetting rates were indeed predicted by the quantity and quality of Spanish use, and
correlated negatively with L1 German and positively with L2 English letter fluency. Attrition rates
were furthermore influenced by prior Spanish proficiency, but not by motivation to maintain
Spanish or non-verbal long-term memory capacity. Overall, this study highlights the importance
of language use for FL retention and sheds light on the complex interplay between language
use and other determinants of attrition.

Abstract

Speech is perceived relative to the speech rate in the context. It is unclear, however, what information listeners use to compute speech rate. The present study examines whether listeners use the number of
syllables per unit time (i.e., syllable rate) as a measure of speech rate, as indexed by subsequent vowel perception. We ran two rate-normalization experiments in which participants heard duration-matched word lists that contained either monosyllabic
vs. bisyllabic words (Experiment 1), or monosyllabic vs. trisyllabic pseudowords (Experiment 2). The participants’ task was to categorize an /ɑ-aː/ continuum that followed the word lists. The monosyllabic condition was perceived as slower (i.e., fewer /aː/ responses) than the bisyllabic and
trisyllabic condition. However, no difference was observed between bisyllabic and trisyllabic contexts. Therefore, while syllable rate is used in perceiving speech rate, other factors, such as fast speech processes, mean F0, and intensity, must also influence rate normalization.

Abstract

When recognizing spoken words, listeners are confronted by variability in the speech signal caused by talker differences. Previous research has focused on segmental talker variability; less is known about how suprasegmental variability is handled. Here we investigated the use of perceptual learning to deal with between-talker differences in lexical stress. Two groups of participants heard Dutch minimal stress pairs (e.g., VOORnaam vs. voorNAAM, “first name” vs. “respectable”) spoken by two male talkers. Group 1 heard Talker 1 use only F0 to signal stress (intensity and duration values were ambiguous), while Talker 2 used only intensity (F0 and duration were ambiguous). Group 2 heard the reverse talker-cue mappings. After training, participants were tested on words from both talkers containing conflicting stress cues (“mixed items”; e.g., one spoken by Talker 1 with F0 signaling initial stress and intensity signaling final stress). We found that listeners used previously learned information about which talker used which cue to interpret the mixed items. For example, the mixed item described above tended to be interpreted as having initial stress by Group 1 but as having final stress by Group 2. This demonstrates that listeners learn how individual talkers signal stress and use that knowledge in spoken-word recognition.

Abstract

Over the course of a conversation, interlocutors sound more and more like each other in a process called convergence. However, the automaticity and grain size of convergence are not well established. This study therefore examined whether female native Dutch speakers converge to large yet sub-phonemic shifts in the F2 of the vowel /e/. Participants first performed a short reading task to establish baseline F2s for the vowel /e/, then shadowed 120 target words (alongside 360 fillers) which contained one instance of a manipulated vowel /e/ where the F2 had been shifted down to that of the vowel /ø/. Consistent exposure to large (sub-phonemic) downward shifts in F2 did not result in convergence. The results raise issues for theories which view convergence as a product of automatic integration between perception and production.

Abstract

It has been suggested that individual variation in vowel compactness of the native language (L1) and the distance between L1 vowels and vowels in the second language (L2) predict successful L2 vowel acquisition. Moreover, general articulatory skills have been proposed to account for variation in vowel compactness. In the present work, we conceptually replicate a previous study to test these hypotheses with a large sample size, a new language pair and a
new vowel pair. We find evidence that individual variation in L1 vowel compactness has opposing effects for two different vowels. We do not find evidence that individual variation in L1 compactness
is explained by general articulatory skills. We conclude that the results found previously might be specific to sub-groups of L2 learners and/or specific sub-sets of vowel pairs.

Abstract

The aim of this study was to investigate whether early-English education benefits the perception
of English phonetic contrasts that are known to be perceptually confusable for Dutch
native speakers, comparing Dutch pupils who were enrolled in an early-English programme
at school from the age of four with pupils in a mainstream programme with English instruction
from the age of 11, and English-Dutch early bilingual children. Children were 4-5-yearolds
(start of primary school), 8-9-year-olds, or 11-12-year-olds (end of primary school).
Children were tested on four contrasts that varied in difficulty: /b/-/s/ (easy), /k/-/ɡ/ (intermediate),
/f/-/θ/ (difficult), /ε/-/æ/ (very difficult). Bilingual children outperformed the two other
groups on all contrasts except /b/-/s/. Early-English pupils did not outperform mainstream
pupils on any of the contrasts. This shows that early-English education as it is currently
implemented is not beneficial for pupils’ perception of non-native contrasts.

Abstract

- * indicates joint first authorship - Lexical access is a core component of word processing. In order to produce or comprehend a word, language users must access word forms in their mental lexicon. However, despite its involvement in both tasks, previous research has often studied lexical access in either production or comprehension alone. Therefore, it is unknown to which extent lexical access processes are shared across both tasks. Picture naming and auditory lexical decision are considered good tools for studying lexical access. Both of them are speeded tasks. Given these commonalities, another open question concerns the involvement of general cognitive abilities (e.g., processing speed) in both linguistic tasks. In the present study, we addressed these questions. We tested a large group of young adults enrolled in academic and vocational courses. Participants completed picture naming and auditory lexical decision tasks as well as a battery of tests assessing non-verbal processing speed, vocabulary, and non-verbal intelligence. Our results suggest that the lexical access processes involved in picture naming and lexical decision are related but less closely than one might have thought. Moreover, reaction times in picture naming and lexical decision depended as least as much on general processing speed as on domain-specific linguistic processes (i.e., lexical access processes).

Abstract

This resource contains data from 112 Dutch adults (18–29 years of age) who completed the Individual Differences in Language Skills test battery that included 33 behavioural tests assessing language skills and domain-general cognitive skills likely involved in language tasks. The battery included tests measuring linguistic experience (e.g. vocabulary size, prescriptive grammar knowledge), general cognitive skills (e.g. working memory, non-verbal intelligence) and linguistic processing skills (word production/comprehension, sentence production/comprehension). Testing was done in a lab-based setting resulting in high quality data due to tight monitoring of the experimental protocol and to the use of software and hardware that were optimized for behavioural testing. Each participant completed the battery twice (i.e., two test days of four hours each). We provide the raw data from all tests on both days as well as pre-processed data that were used to calculate various reliability measures (including internal consistency and test-retest reliability). We encourage other researchers to use this resource for conducting exploratory and/or targeted analyses of individual differences in language and general cognitive skills.

Abstract

This chapter outlines a Bayesian model of spoken-word recognition and reviews how
prosody is part of that model. The review focuses on the information that assists the lis­
tener in recognizing the prosodic structure of an utterance and on how spoken-word
recognition is also constrained by prior knowledge about prosodic structure. Recognition
is argued to be a process of perceptual inference that ensures that listening is robust to
variability in the speech signal. In essence, the listener makes inferences about the seg­
mental content of each utterance, about its prosodic structure (simultaneously at differ­
ent levels in the prosodic hierarchy), and about the words it contains, and uses these in­
ferences to form an utterance interpretation. Four characteristics of the proposed
prosody-enriched recognition model are discussed: parallel uptake of different informa­
tion types, high contextual dependency, adaptive processing, and phonological abstrac­
tion. The next steps that should be taken to develop the model are also discussed.

Abstract

Learning new words entails, inter alia, encoding of novel sound patterns and transferring those patterns from short-term to long-term memory. We report a series of 5 experiments that investigated whether the memory systems engaged in word learning are specialized for speech and whether utilization of these systems results in a benefit for word learning. Sine-wave synthesis (SWS) was applied to spoken nonwords, and listeners were or were not informed (through instruction and familiarization) that the SWS stimuli were derived from actual utterances. This allowed us to manipulate whether listeners would process sound sequences as speech or as nonspeech. In a sound–picture association learning task, listeners who processed the SWS stimuli as speech consistently learned faster and remembered more associations than listeners who processed the same stimuli as nonspeech. The advantage of listening in “speech mode” was stable over the course of 7 days. These results provide causal evidence that access to a specialized, phonological short-term memory system is important for word learning. More generally, this study supports the notion that subsystems of auditory short-term memory are specialized for processing different types of acoustic information.

Abstract

Research in the domain of memory suggests that forgetting is primarily driven by interference and competition from other, related memories. Here we ask whether similar dynamics are at play in foreign language (FL) attrition. We tested whether interference from translation equivalents in other, more recently used languages causes subsequent retrieval failure in L3. In Experiment 1, we investigated whether interference from the native language (L1) and/or from another foreign language (L2) affected L3 vocabulary retention. On day 1, Dutch native speakers learned 40 new Spanish (L3) words. On day 2, they performed a number of retrieval tasks in either Dutch (L1) or English (L2) on half of these words, and then memory for all items was tested again in L3 Spanish. Recall in Spanish was slower and less complete for words that received interference than for words that did not. In naming speed, this effect was larger for L2 compared to L1 interference. Experiment 2 replicated the interference effect and asked if the language difference can be explained by frequency of use differences between native- and non-native languages. Overall, these findings suggest that competition from more recently used languages, and especially other foreign languages, is a driving force behind FL attrition.

Abstract

We investigated music and language processing in a group of early bilinguals who spoke a tone language and a non-tone language (Cantonese and Dutch). We assessed online speech-music processing interactions, that is, interactions that occur when speech and music are processed simultaneously in songs, with a speeded classification task. In this task, participants judged sung pseudowords either musically (based on the direction of the musical interval) or phonologically (based on the identity of the sung vowel). We also assessed longer-term effects of linguistic experience on musical ability, that is, the influence of extensive prior experience with language when processing music. These effects were assessed with a task in which participants had to learn to identify musical intervals and with four pitch-perception tasks. Our hypothesis was that due to their experience in two different languages using lexical versus intonational tone, the early Cantonese-Dutch bilinguals would outperform the Dutch control participants. In online processing, the Cantonese-Dutch bilinguals processed speech and music more holistically than controls. This effect seems to be driven by experience with a tone language, in which integration of segmental and pitch information is fundamental. Regarding longer-term effects of linguistic experience, we found no evidence for a bilingual advantage in either the music-interval learning task or the pitch-perception tasks. Together, these results suggest that being a Cantonese-Dutch bilingual does not have any measurable longer-term effects on pitch and music processing, but does have consequences for how speech and music are processed jointly.

Abstract

The complementary learning systems account of word learning states that novel words, like other types of memories, undergo an offline consolidation process during which they are gradually integrated into the neocortical memory network. A fundamental change in the neural representation of a novel word should therefore occur in the hours after learning. The present EEG study tested this hypothesis by investigating whether novel words learned before a 24-hr consolidation period elicited more word-like oscillatory responses than novel words learned immediately before testing. In line with previous studies indicating that theta synchronization reflects lexical access, unfamiliar novel words elicited lower power in the theta band (4–8 Hz) than existing words. Recently learned words still showed a marginally lower theta increase than existing words, but theta responses to novel words that had been acquired 24 hr earlier were indistinguishable from responses to existing words. Consistent with evidence that beta desynchronization (16–21 Hz) is related to lexical-semantic processing, we found that both unfamiliar and recently learned novel words elicited less beta desynchronization than existing words. In contrast, no difference was found between novel words learned 24 hr earlier and existing words. These data therefore suggest that an offline consolidation period enables novel words to acquire lexically integrated, word-like neural representations.

Abstract

This study aims to test a prediction of recent
theoretical frameworks in speech motor control: if speech production targets are specified in auditory
terms, people with better auditory acuity should have more precise speech targets.
To investigate this, we had participants perform speech perception and production tasks in a counterbalanced order. To assess speech perception acuity, we used an adaptive speech discrimination
task. To assess variability in speech production, participants performed a pseudo-word reading task; formant values were measured for each recording.
We predicted that speech production variability to correlate inversely with discrimination performance.
The results suggest that people do vary in their production and perceptual abilities, and that better discriminators have more distinctive vowel production targets, confirming our prediction. This
study highlights the importance of individual
differences in the study of speech motor control, and sheds light on speech production-perception interaction.

Abstract

Children who start formal education in a second language may experience slower vocabulary growth in that language and subsequently experience disadvantages in literacy acquisition. The current study asked whether lexical specificity training can stimulate bilingual children's phonological awareness, which is considered to be a precursor to literacy. Therefore, Dutch monolingual and Turkish-Dutch bilingual children were taught new Dutch words with only minimal acoustic-phonetic differences. As a result of this training, the monolingual and the bilingual children improved on phoneme blending, which can be seen as an early aspect of phonological awareness. During training, the bilingual children caught up with the monolingual children on words with phonological overlap between their first language Turkish and their second language Dutch. It is concluded that learning minimal pair words fosters phoneme awareness, in both first and second language preliterate children, and that for second language learners phonological overlap between the two languages positively affects training outcomes, likely due to linguistic transfer

Abstract

This study asks how users of British Sign Language (BSL) recognize individual signs in connected sign sequences. We examined whether this is achieved through modality-specific or modality-general segmentation procedures. A modality-specific feature of signed languages is that, during continuous signing, there are salient transitions between sign locations. We used the sign-spotting task to ask if and how BSL signers use these transitions in segmentation. A total of 96 real BSL signs were preceded by nonsense signs which were produced in either the target location or another location (with a small or large transition). Half of the transitions were within the same major body area (e.g., head) and half were across body areas (e.g., chest to hand). Deaf adult BSL users (a group of natives and early learners, and a group of late learners) spotted target signs best when there was a minimal transition and worst when there was a large transition. When location changes were present, both groups performed better when transitions were to a different body area than when they were within the same area. These findings suggest that transitions do not provide explicit sign-boundary cues in a modality-specific fashion. Instead, we argue that smaller transitions help recognition in a modality-general way by limiting lexical search to signs within location neighbourhoods, and that transitions across body areas also aid segmentation in a modality-general way, by providing a phonotactic cue to a sign boundary. We propose that sign segmentation is based on modality-general procedures which are core language-processing mechanisms

Abstract

In different tasks involving action perception, performance has been found to be facilitated
when the presented stimuli were produced by the participants themselves rather than by
another participant. These results suggest that the same mental representations are
accessed during both production and perception. However, with regard to spoken word perception,
evidence also suggests that listeners’ representations for speech reflect the input
from their surrounding linguistic community rather than their own idiosyncratic productions.
Furthermore, speech perception is heavily influenced by indexical cues that may lead listeners
to frame their interpretations of incoming speech signals with regard to speaker identity.
In order to determine whether word recognition evinces similar self-advantages as found in
action perception, it was necessary to eliminate indexical cues from the speech signal. We therefore asked participants to identify noise-vocoded versions of Dutch words that were based on either their own recordings or those of a statistically average speaker. The majority of participants were more accurate for the average speaker than for themselves, even after taking into account differences in intelligibility. These results suggest that the speech
representations accessed during perception of noise-vocoded speech are more reflective
of the input of the speech community, and hence that speech perception is not necessarily based on representations of one’s own speech.

Abstract

In three cross-modal priming experiments we asked whether adaptation to a foreign-accented speaker is automatic, and whether adaptation can be seen after a long delay between initial exposure and test. Dutch listeners were exposed to a Hebrew-accented Dutch speaker with two types of Dutch words: those that contained [ɪ] (globally accented words), and those in which the Dutch [i] was shortened to [ɪ] (specific accent marker words). Experiment 1, which served as a baseline, showed that native Dutch participants showed facilitatory priming for globally accented, but not specific accent, words. In experiment 2, participants performed a 3.5-minute phoneme monitoring task, and were tested on their comprehension of the accented speaker 24 hours later using the same cross-modal priming task as in experiment 1. During the phoneme monitoring task, listeners were asked to detect a consonant that was not strongly accented. In experiment 3, the delay between exposure and test was extended to 1 week. Listeners in experiments 2 and 3 showed facilitatory priming for both globally accented and specific accent marker words. Together, these results show that adaptation to a foreign-accented speaker can be rapid and automatic, and can be observed after a prolonged delay in testing.