Observed and Performed Error Signals in Auditory Lexical Decisions.

This study investigates the error processing components in the EEG signal of Performers and Observers using an auditory lexical decision task, in which participants heard spoken items and decided for each item if it was a real word or not. Pairs of participants were tested in both the role of the Performer and the Observer. In the literature, an Error Related Negativity (ERN)-Error Positivity (Pe) complex has been identified for performed (ERN-Pe) and observed (oERN-oPe) errors. While these effects have been widely studied for performance errors in speeded decision tasks relying on visual input, relatively little is known about the performance monitoring signatures in observed language processing based on auditory input. In the lexical decision task, native Dutch speakers listened to real Dutch Words, Non-Words, and crucially, long Pseudowords that resembled words until the final syllable and were shown to be error-prone in a pilot study, because they were responded to too soon. We hypothesised that the errors in the task would result in a response locked ERN-Pe pattern both for the Performer and for the Observer. Our hypothesis regarding the ERN was not supported, however a Pe-like effect, as well as a P300 were present. Analyses to disentangle lexical and error processing similarly indicated a P300 for errors, and the results furthermore pointed to differences between responses before and after word offset. The findings are interpreted as marking attention during error processing during auditory word recognition.

Asymmetric memory for birth language perception versus production in young international adoptees.

Adults who as children were adopted into a different linguistic community retain knowledge of their birth language. The possession (without awareness) of such knowledge is known to facilitate the (re)learning of birth-language speech patterns; this perceptual learning predicts such adults' production success as well, indicating that the retained linguistic knowledge is abstract in nature. Adoptees' acquisition of their adopted language is fast and complete; birth-language mastery disappears rapidly, although this latter process has been little studied. Here, 46 international adoptees from China aged four to 10 years, with Dutch as their new language, plus 47 matched non-adopted Dutch-native controls and 40 matched non-adopted Chinese controls, undertook across a two-week period 10 blocks of training in perceptually identifying Chinese speech contrasts (one segmental, one tonal) which were unlike any Dutch contrasts. Chinese controls easily accomplished all these tasks. The same participants also provided speech production data in an imitation task. In perception, adoptees and Dutch controls scored equivalently poorly at the outset of training; with training, the adoptees significantly improved while the Dutch controls did not. In production, adoptees' imitations both before and after training could be better identified, and received higher goodness ratings, than those of Dutch controls. The perception results confirm that birth-language knowledge is stored and can facilitate re-learning in post-adoption childhood; the production results suggest that although processing of phonological category detail appears to depend on access to the stored knowledge, general articulatory dimensions can at this age also still be remembered, and may facilitate spoken imitation.

Dutch listeners' perception of English lexical stress: A cue-weighting approach.

We investigate whether acoustic cue weightings are transferred from the native language to the second language [research question 1 (RQ1)], how cue weightings change with increasing second-language proficiency (RQ2), and whether individual cues are used independently or together in the second language (RQ3). Vowel reduction is a strong cue to lexical stress in English but not Dutch. Native English listeners and Dutch second-language learners of English completed a cue-weighting stress perception experiment. Participants heard sentence-final pitch-accented auditory stimuli and identified them as DEsert (initial stress) or deSSERT (final stress). The stimuli were manipulated in seven steps from initial to final stress, manipulating two dimensions at a time: vowel quality and pitch, vowel quality and duration, and pitch and duration (other dimensions neutralized). Dutch listeners relied less on vowel quality and more on pitch than English listeners, with Dutch listeners' sensitivity to vowel quality increasing with English proficiency but their sensitivity to pitch not varying with proficiency; Dutch listeners evidenced similar or weaker reliance on duration than did English listeners, and their sensitivity to duration increased with proficiency; and Dutch listeners' use of pitch and duration were positively related. These results provide general support for a cue-based transfer approach to the perception of lexical stress.

Perception of English phonetic contrasts by Dutch children: How bilingual are early-English learners?

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-year-olds (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/-/É¡/ (intermediate), /f/-/θ/ (difficult), /ɛ/-/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.

Language balance and switching ability in children acquiring English as a second language.

This study investigated whether relative lexical proficiency in Dutch and English in child second language (L2) learners is related to executive functioning. Participants were Dutch primary school pupils of three different age groups (4-5, 8-9, and 11-12 years) who either were enrolled in an early-English schooling program or were age-matched controls not on that early-English program. Participants performed tasks that measured switching, inhibition, and working memory. Early-English program pupils had greater knowledge of English vocabulary and more balanced Dutch-English lexicons. In both groups, lexical balance, a ratio measure obtained by dividing vocabulary scores in English by those in Dutch, was related to switching but not to inhibition or working memory performance. These results show that for children who are learning an L2 in an instructional setting, and for whom managing two languages is not yet an automatized process, language balance may be more important than L2 proficiency in influencing the relation between childhood bilingualism and switching abilities.

Experience with a second language affects the use of fundamental frequency in speech segmentation.

This study investigates whether listeners' experience with a second language learned later in life affects their use of fundamental frequency (F0) as a cue to word boundaries in the segmentation of an artificial language (AL), particularly when the cues to word boundaries conflict between the first language (L1) and second language (L2). F0 signals phrase-final (and thus word-final) boundaries in French but word-initial boundaries in English. Participants were functionally monolingual French listeners, functionally monolingual English listeners, bilingual L1-English L2-French listeners, and bilingual L1-French L2-English listeners. They completed the AL-segmentation task with F0 signaling word-final boundaries or without prosodic cues to word boundaries (monolingual groups only). After listening to the AL, participants completed a forced-choice word-identification task in which the foils were either non-words or part-words. The results show that the monolingual French listeners, but not the monolingual English listeners, performed better in the presence of F0 cues than in the absence of such cues. Moreover, bilingual status modulated listeners' use of F0 cues to word-final boundaries, with bilingual French listeners performing less accurately than monolingual French listeners on both word types but with bilingual English listeners performing more accurately than monolingual English listeners on non-words. These findings not only confirm that speech segmentation is modulated by the L1, but also newly demonstrate that listeners' experience with the L2 (French or English) affects their use of F0 cues in speech segmentation. This suggests that listeners' use of prosodic cues to word boundaries is adaptive and non-selective, and can change as a function of language experience.

Early phonology revealed by international adoptees' birth language retention.

Until at least 6 mo of age, infants show good discrimination for familiar phonetic contrasts (i.e., those heard in the environmental language) and contrasts that are unfamiliar. Adult-like discrimination (significantly worse for nonnative than for native contrasts) appears only later, by 9-10 mo. This has been interpreted as indicating that infants have no knowledge of phonology until vocabulary development begins, after 6 mo of age. Recently, however, word recognition has been observed before age 6 mo, apparently decoupling the vocabulary and phonology acquisition processes. Here we show that phonological acquisition is also in progress before 6 mo of age. The evidence comes from retention of birth-language knowledge in international adoptees. In the largest ever such study, we recruited 29 adult Dutch speakers who had been adopted from Korea when young and had no conscious knowledge of Korean language at all. Half were adopted at age 3-5 mo (before native-specific discrimination develops) and half at 17 mo or older (after word learning has begun). In a short intensive training program, we observe that adoptees (compared with 29 matched controls) more rapidly learn tripartite Korean consonant distinctions without counterparts in their later-acquired Dutch, suggesting that the adoptees retained phonological knowledge about the Korean distinction. The advantage is equivalent for the younger-adopted and the older-adopted groups, and both groups not only acquire the tripartite distinction for the trained consonants but also generalize it to untrained consonants. Although infants younger than 6 mo can still discriminate unfamiliar phonetic distinctions, this finding indicates that native-language phonological knowledge is nonetheless being acquired at that age.

Early development of abstract language knowledge: evidence from perception-production transfer of birth-language memory.

Children adopted early in life into another linguistic community typically forget their birth language but retain, unaware, relevant linguistic knowledge that may facilitate (re)learning of birth-language patterns. Understanding the nature of this knowledge can shed light on how language is acquired. Here, international adoptees from Korea with Dutch as their current language, and matched Dutch-native controls, provided speech production data on a Korean consonantal distinction unlike any Dutch distinctions, at the outset and end of an intensive perceptual training. The productions, elicited in a repetition task, were identified and rated by Korean listeners. Adoptees' production scores improved significantly more across the training period than control participants' scores, and, for adoptees only, relative production success correlated significantly with the rate of learning in perception (which had, as predicted, also surpassed that of the controls). Of the adoptee group, half had been adopted at 17 months or older (when talking would have begun), while half had been prelinguistic (under six months). The former group, with production experience, showed no advantage over the group without. Thus the adoptees' retained knowledge of Korean transferred from perception to production and appears to be abstract in nature rather than dependent on the amount of experience.

Cognate Costs in Bilingual Speech Production: Evidence from Language Switching.

This study investigates cross-language lexical competition in the bilingual mental lexicon. It provides evidence for the occurrence of inhibition as well as the commonly reported facilitation during the production of cognates (words with similar phonological form and meaning in two languages) in a mixed picture naming task by highly proficient Welsh-English bilinguals. Previous studies have typically found cognate facilitation. It has previously been proposed (with respect to non-cognates) that cross-language inhibition is limited to low-proficient bilinguals; therefore, we tested highly proficient, early bilinguals. In a mixed naming experiment (i.e., picture naming with language switching), 48 highly proficient, early Welsh-English bilinguals named pictures in Welsh and English, including cognate and non-cognate targets. Participants were English-dominant, Welsh-dominant, or had equal language dominance. The results showed evidence for cognate inhibition in two ways. First, both facilitation and inhibition were found on the cognate trials themselves, compared to non-cognate controls, modulated by the participants' language dominance. The English-dominant group showed cognate inhibition when naming in Welsh (and no difference between cognates and controls when naming in English), and the Welsh-dominant and equal dominance groups generally showed cognate facilitation. Second, cognate inhibition was found as a behavioral adaptation effect, with slower naming for non-cognate filler words in trials after cognates than after non-cognate controls. This effect was consistent across all language dominance groups and both target languages, suggesting that cognate production involved cognitive control even if this was not measurable in the cognate trials themselves. Finally, the results replicated patterns of symmetrical switch costs, as commonly reported for balanced bilinguals. We propose that cognate processing might be affected by two different processes, namely competition at the lexical-semantic level and facilitation at the word form level, and that facilitation at the word form level might (sometimes) outweigh any effects of inhibition at the lemma level. In sum, this study provides evidence that cognate naming can cause costs in addition to benefits. The finding of cognate inhibition, particularly for the highly proficient bilinguals tested, provides strong evidence for the occurrence of lexical competition across languages in the bilingual mental lexicon.

Effects of the Native Language on the Learning of Fundamental Frequency in Second-Language Speech Segmentation.

This study investigates whether the learning of prosodic cues to word boundaries in speech segmentation is more difficult if the native and second/foreign languages (L1 and L2) have similar (though non-identical) prosodies than if they have markedly different prosodies (Prosodic-Learning Interference Hypothesis). It does so by comparing French, Korean, and English listeners' use of fundamental-frequency (F0) rise as a cue to word-final boundaries in French. F0 rise signals phrase-final boundaries in French and Korean but word-initial boundaries in English. Korean-speaking and English-speaking L2 learners of French, who were matched in their French proficiency and French experience, and native French listeners completed a visual-world eye-tracking experiment in which they recognized words whose final boundary was or was not cued by an increase in F0. The results showed that Korean listeners had greater difficulty using F0 rise as a cue to word-final boundaries in French than French and English listeners. This suggests that L1-L2 prosodic similarity can make the learning of an L2 segmentation cue difficult, in line with the proposed Prosodic-Learning Interference Hypothesis. We consider mechanisms that may underlie this difficulty and discuss the implications of our findings for understanding listeners' phonological encoding of L2 words.

Overspecification of color, pattern, and size: salience, absoluteness, and consistency.

The rates of overspecification of color, pattern, and size are compared, to investigate how salience and absoluteness contribute to the production of overspecification. Color and pattern are absolute and salient attributes, whereas size is relative and less salient. Additionally, a tendency toward consistent responses is assessed. Using a within-participants design, we find similar rates of color and pattern overspecification, which are both higher than the rate of size overspecification. Using a between-participants design, however, we find similar rates of pattern and size overspecification, which are both lower than the rate of color overspecification. This indicates that although many speakers are more likely to include color than pattern (probably because color is more salient), they may also treat pattern like color due to a tendency toward consistency. We find no increase in size overspecification when the salience of size is increased, suggesting that speakers are more likely to include absolute than relative attributes. However, we do find an increase in size overspecification when mentioning the attributes is triggered, which again shows that speakers tend to refer in a consistent manner, and that there are circumstances in which even size overspecification is frequently produced.

Normal-Hearing Listeners' and Cochlear Implant Users' Perception of Pitch Cues in Emotional Speech.

In cochlear implants (CIs), acoustic speech cues, especially for pitch, are delivered in a degraded form. This study's aim is to assess whether due to degraded pitch cues, normal-hearing listeners and CI users employ different perceptual strategies to recognize vocal emotions, and, if so, how these differ. Voice actors were recorded pronouncing a nonce word in four different emotions: anger, sadness, joy, and relief. These recordings' pitch cues were phonetically analyzed. The recordings were used to test 20 normal-hearing listeners' and 20 CI users' emotion recognition. In congruence with previous studies, high-arousal emotions had a higher mean pitch, wider pitch range, and more dominant pitches than low-arousal emotions. Regarding pitch, speakers did not differentiate emotions based on valence but on arousal. Normal-hearing listeners outperformed CI users in emotion recognition, even when presented with CI simulated stimuli. However, only normal-hearing listeners recognized one particular actor's emotions worse than the other actors'. The groups behaved differently when presented with similar input, showing that they had to employ differing strategies. Considering the respective speaker's deviating pronunciation, it appears that for normal-hearing listeners, mean pitch is a more salient cue than pitch range, whereas CI users are biased toward pitch range cues.

Introducing LexTALE: a quick and valid Lexical Test for Advanced Learners of English.

The increasing number of experimental studies on second language (L2) processing, frequently with English as the L2, calls for a practical and valid measure of English vocabulary knowledge and proficiency. In a large-scale study with Dutch and Korean speakers of L2 English, we tested whether LexTALE, a 5-min vocabulary test, is a valid predictor of English vocabulary knowledge and, possibly, even of general English proficiency. Furthermore, the validity of LexTALE was compared with that of self-ratings of proficiency, a measure frequently used by L2 researchers. The results showed the following in both speaker groups: (1) LexTALE was a good predictor of English vocabulary knowledge; 2) it also correlated substantially with a measure of general English proficiency; and 3) LexTALE was generally superior to self-ratings in its predictions. LexTALE, but not self-ratings, also correlated highly with previous experimental data on two word recognition paradigms. The test can be carried out on or downloaded from www.lextale.com .

Competition dynamics of second-language listening.

Spoken-word recognition in a nonnative language is particularly difficult where it depends on discrimination between confusable phonemes. Four experiments here examine whether this difficulty is in part due to phantom competition from "near-words" in speech. Dutch listeners confuse English /æ/ and /ε/, which could lead to the sequence daf being interpreted as deaf, or lemp being interpreted as lamp. In auditory lexical decision, Dutch listeners indeed accepted such near-words as real English words more often than English listeners did. In cross-modal priming, near-words extracted from word or phrase contexts (daf from DAFfodil, lemp from eviL EMPire) induced activation of corresponding real words (deaf; lamp) for Dutch, but again not for English, listeners. Finally, by the end of untruncated carrier words containing embedded words or near-words (definite; daffodil) no activation of the real embedded forms (deaf in definite) remained for English or Dutch listeners, but activation of embedded near-words (deaf in daffodil) did still remain, for Dutch listeners only. Misinterpretation of the initial vowel here favoured the phantom competitor and disfavoured the carrier (lexically represented as containing a different vowel). Thus, near-words compete for recognition and continue competing for longer than actually embedded words; nonnative listening indeed involves phantom competition.

Perception of final fricative voicing: native and nonnative listeners' use of vowel duration.

Does experience with a perceptual cue for a phoneme contrast in the native language affect its use in a second language for a similar contrast in a different phonetic context? Two experiments investigated Dutch and English listeners' use of preceding vowel duration as a perceptual cue for nonword-final fricative voicing in English. Dutch listeners have native language experience with the use of vowel duration for vowel length and intervocalic obstruent voicing contrasts, but not for final voicing contrasts, as Dutch does not have voiced obstruents word-finally. Previous research [Broersma, M. (2005). J. Acoust. Soc. Am. 117, 3890-3901; Broersma, M.(2008) J. Acoust. Soc. Am.124, 712-715] showed that Dutch listeners used vowel duration less for final /v-f/ categorization than English listeners did when vowel duration varied only between subjects, discouraging its use as a perceptual cue. The present study assessed the use of vowel duration for final /v-f/ and /z-s/ contrasts when it varied within subjects. A goodness rating and a phonetic categorization experiment showed that Dutch listeners used vowel duration, but less than English listeners did. Thus, experience with a perceptual cue for a different contrast and for a similar contrast in a different position in the native language did not lead to native-like use of this cue in the second language.

Flexible cue use in nonnative phonetic categorization.

Native and nonnative listeners categorized final /v/ versus /f/ in English nonwords. Fricatives followed phonetically long (originally /v/-preceding) or short (originally /f/-preceding) vowels. Vowel duration was constant for each participant and sometimes mismatched other voicing cues. Previous results showed that English but not Dutch listeners (whose L1 has no final voicing contrast) nevertheless used the misleading vowel duration for /v/-/f/ categorization. New analyses showed that Dutch listeners did use vowel duration initially, but quickly reduced its use, whereas the English listeners used it consistently throughout the experiment. Thus, nonnative listeners adapted to the stimuli more flexibly than native listeners did.

Perception of familiar contrasts in unfamiliar positions.

This paper investigates the perception of non-native phoneme contrasts which exist in the native language, but not in the position tested. Like English, Dutch contrasts voiced and voiceless obstruents. Unlike English, Dutch allows only voiceless obstruents in word-final position. Dutch and English listeners' accuracy on English final voicing contrasts and their use of preceding vowel duration as a voicing cue were tested. The phonetic structure of Dutch should provide the necessary experience for a native-like use of this cue. Experiment 1 showed that Dutch listeners categorized English final /z/-/s/, /v/-/f/, /b/-/p/, and /d/-/t/ contrasts in nonwords as accurately as initial contrasts, and as accurately as English listeners did, even when release bursts were removed. In experiment 2, English listeners used vowel duration as a cue for one final contrast, although it was uninformative and sometimes mismatched other voicing characteristics, whereas Dutch listeners did not. Although it should be relatively easy for them, Dutch listeners did not use vowel duration. Nevertheless, they attained native-like accuracy, and sometimes even outperformed the native listeners who were liable to be misled by uninformative vowel duration information. Thus, native-like use of cues for non-native but familiar contrasts in unfamiliar positions may hardly ever be attained.