Publications

Abstract

Several studies have documented that international adoptees, who in early years have
experienced a change from a language used in their birth country to a new language
in an adoptive country, benefit from the limited early exposure to the birth language
when relearning that language’s sounds later in life. The adoptees’ relearning advantages
have been argued to be conferred by lasting birth-language knowledge obtained from
the early exposure. However, it is also plausible to assume that the advantages may
arise from adoptees’ superior ability to learn language sounds in general, as a result
of their unusual linguistic experience, i.e., exposure to multiple languages in sequence
early in life. If this is the case, then the adoptees’ relearning benefits should generalize
to previously unheard language sounds, rather than be limited to their birth-language
sounds. In the present study, adult Korean adoptees in the Netherlands and matched
Dutch-native controls were trained on identifying a Japanese length distinction to which
they had never been exposed before. The adoptees and Dutch controls did not differ
on any test carried out before, during, or after the training, indicating that observed
adoptee advantages for birth-language relearning do not generalize to novel, previously
unheard language sounds. The finding thus fails to support the suggestion that
birth-language relearning advantages may arise from enhanced ability to learn language
sounds in general conferred by early experience in multiple languages. Rather, our
finding supports the original contention that such advantages involve memory traces
obtained before adoption

Abstract

Listeners' recognition of spoken language involves complex decoding processes: The continuous speech stream must be segmented into its component words, and words must be recognized despite great variability in their pronunciation (due to talker differences, or to influence of phonetic context, or to speech register) and despite competition from many spuriously present forms supported by the speech signal. L1 listeners deal more readily with all levels of this complexity than L2 listeners. Fortunately, the decoding processes necessary for competent L2 listening can be taught in the classroom. Evidence-based methodologies targeted at the development of efficient speech decoding include teaching of minimal pairs, of phonotactic constraints, and of reduction processes, as well as the use of dictation and L2 video captions.

Abstract

Talkers are recognized more accurately if they are speaking the listeners’ native language rather than an unfamiliar language. This “language familiarity effect” has been shown not to depend upon comprehension and must instead involve language sound patterns. We further examine the level of sound-pattern processing involved, by comparing talker recognition in foreign languages versus two varieties of English, by (a) English speakers of one variety, (b) English speakers of the other variety, and (c) non-native listeners (more familiar with one of the varieties). All listener groups performed better with native than foreign speech, but no effect of language variety appeared: Native listeners discriminated talkers equally well in each, with the native variety never outdoing the other variety, and non-native listeners discriminated talkers equally poorly in each, irrespective of the variety's familiarity. The results suggest that this talker recognition effect rests not on simple familiarity, but on an abstract level of phonological processing

Abstract

We report a large‐scale electrophysiological study of infant speech segmentation, in which over 100 English‐acquiring 9‐month‐olds were exposed to unfamiliar bisyllabic words embedded in sentences (e.g., He saw a wild eagle up there), after which their brain responses to either the just‐familiarized word (eagle) or a control word (coral) were recorded. When initial exposure occurs in continuous speech, as here, past studies have reported that even somewhat older infants do not reliably recognize target words, but that successful segmentation varies across children. Here, we both confirm and further uncover the nature of this variation. The segmentation response systematically varied across individuals and was related to their vocabulary development. About one‐third of the group showed a left‐frontally located relative negativity in response to familiar versus control targets, which has previously been described as a mature response. Another third showed a similarly located positive‐going reaction (a previously described immature response), and the remaining third formed an intermediate grouping that was primarily characterized by an initial response delay. A fine‐grained group‐level analysis suggested that a developmental shift to a lexical mode of processing occurs toward the end of the first year, with variation across individual infants in the exact timing of this shift.

Abstract

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.

Abstract

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.

Abstract

Background/Aims: Evidence from spoken word recognition suggests that for English listeners, distinguishing full versus reduced vowels is important, but discerning stress differences involving the same full vowel (as in mu- from music or museum) is not. In Dutch, in contrast, the latter distinction is important. This difference arises from the relative frequency of unstressed full vowels in the two vocabularies. The goal of this paper is to determine how this difference in the lexicon influences the perception of stressed versus unstressed vowels. Methods: All possible sequences of two segments (diphones) in Dutch and in English were presented to native listeners in gated fragments. We recorded identification performance over time throughout the speech signal. The data were here analysed specifically for patterns in perception of stressed versus unstressed vowels. Results: The data reveal significantly larger stress effects (whereby unstressed vowels are harder to identify than stressed vowels) in English than in Dutch. Both language-specific and shared patterns appear regarding which vowels show stress effects. Conclusion: We explain the larger stress effect in English as reflecting the processing demands caused by the difference in use of unstressed vowels in the lexicon. The larger stress effect in English is due to relative inexperience with processing unstressed full vowels

Abstract

English listeners largely disregard suprasegmental cues to stress in recognizing words. Evidence for this includes the demonstration of Fear et al. [J. Acoust. Soc. Am. 97, 1893–1904 (1995)] that cross-splicings are tolerated between stressed and unstressed full vowels (e.g., au- of autumn, automata). Dutch listeners, however, do exploit suprasegmental stress cues in recognizing native-language words. In this study, Dutch listeners were presented with English materials from the study of Fear et al. Acceptability ratings by these listeners revealed sensitivity to suprasegmental mismatch, in particular, in replacements of unstressed full vowels by higher-stressed vowels, thus evincing greater sensitivity to prosodic goodness than had been shown by the original native listener group.

Abstract

Three experiments, in which Japanese listeners detected Japanese words embedded in nonsense sequences, examined the perceptual consequences of vowel devoicing in that language. Since vowelless sequences disrupt speech segmentation [Norris et al. (1997). Cognit. Psychol. 34, 191– 243], devoicing is potentially problematic for perception. Words in initial position in nonsense sequences were detected more easily when followed by a sequence containing a vowel than by a vowelless segment (with or without further context), and vowelless segments that were potential devoicing environments were no easier than those not allowing devoicing. Thus asa, “morning,” was easier in asau or asazu than in all of asap, asapdo, asaf, or asafte, despite the fact that the /f/ in the latter two is a possible realization of fu, with devoiced [u]. Japanese listeners thus do not treat devoicing contexts as if they always contain vowels. Words in final position in nonsense sequences, however, produced a different pattern: here, preceding vowelless contexts allowing devoicing impeded word detection less strongly (so, sake was detected less accurately, but not less rapidly, in nyaksake—possibly arising from nyakusake—than in nyagusake). This is consistent with listeners treating consonant sequences as potential realizations of parts of existing lexical candidates wherever possible.

Abstract

Recognizing word boundaries in continuous speech requires detailed knowledge of the native language. In the first year of life, infants acquire considerable word segmentation abilities. Infants at this early stage in word segmentation rely to a large extent on the metrical pattern of their native language, at least in stress-based languages. In Dutch and English (both languages with a preferred trochaic stress pattern), segmentation of strong-weak words develops rapidly between 7 and 10 months of age. Nevertheless, trochaic languages contain not only strong-weak words but also words with a weak-strong stress pattern. In this article, we present electrophysiological evidence of the beginnings of weak-strong word segmentation in Dutch 10-month-olds. At this age, the ability to combine different cues for efficient word segmentation does not yet seem to be completely developed. We provide evidence that Dutch infants still largely rely on strong syllables, even for the segmentation of weak-strong words.

Abstract

Two artificial-language learning experiments directly compared English, French, and Dutch listeners’ use of suprasegmental cues for continuous-speech segmentation. In both experiments, listeners heard unbroken sequences of consonant-vowel syllables, composed of recurring three- and four-syllable “words.” These words were demarcated by(a) no cue other than transitional probabilities induced by their recurrence, (b) a consistent left-edge cue, or (c) a consistent right-edge cue. Experiment 1 examined a vowel lengthening cue. All three listener groups benefited from this cue in right-edge position; none benefited from it in left-edge position. Experiment 2 examined a pitch-movement cue. English listeners used this cue in left-edge position, French listeners used it in right-edge position, and Dutch listeners used it in both positions. These findings are interpreted as evidence of both language-universal and language-specific effects. Final lengthening is a language-universal effect expressing a more general (non-linguistic) mechanism. Pitch movement expresses prominence which has characteristically different placements across languages: typically at right edges in French, but at left edges in English and Dutch. Finally, stress realization in English versus Dutch encourages greater attention to suprasegmental variation by Dutch than by English listeners, allowing Dutch listeners to benefit from an informative pitch-movement cue even in an uncharacteristic position.

Abstract

Four cross-modal priming experiments and two forced-choice identification experiments investigated the use of suprasegmental cues to stress in the recognition of spoken English words, by native (English-speaking) and non- native (Dutch) listeners. Previous results had indicated that suprasegmental information was exploited in lexical access by Dutch but not by English listeners. For both listener groups, recognition of visually presented target words was faster, in comparison to a control condition, after stress-matching spoken primes, either monosyllabic (mus- from MUsic /muSEum) or bisyl labic (admi- from ADmiral/admiRAtion). For native listeners, the effect of stress-mismatching bisyllabic primes was not different from that of control primes, but mismatching monosyllabic primes produced partial facilitation. For non-native listeners, both bisyllabic and monosyllabic stress-mismatching primes produced partial facilitation. Native English listeners thus can exploit suprasegmental information in spoken-word recognition, but information from two syllables is used more effectively than information from one syllable. Dutch listeners are less proficient at using suprasegmental information in English than in their native language, but, as in their native language, use mono- and bisyllabic information to an equal extent. In forced-choice identification, Dutch listeners outperformed native listeners at correctly assigning a monosyllabic fragment (e.g., mus-) to one of two words differing in stress.

Abstract

Rhythmic categories such as morae in Japanese or stress units in English play a role in the perception of spoken
language. We examined this role in Japanese, since recent evidence suggests that morae may intervene as
structural units in word recognition. First, we found that traditional puns more often substituted part of a mora
than a whole mora. Second, when listeners reconstructed distorted words, e.g. panorama from panozema, responses
were faster and more accurate when only a phoneme was distorted (panozama, panorema) than when a
whole CV mora was distorted (panozema). Third, lexical decisions on the same nonwords were better predicted
by duration and number of phonemes from nonword uniqueness point to word end than by number of morae. Our
results indicate no role for morae in early spoken-word processing; we propose that rhythmic categories constrain
not initial lexical activation but subsequent processes of speech segmentation and selection among word candidates.

Abstract

Speech segmentation procedures may differ in speakers of different languages. Earlier work based on French speakers listening to French words suggested that the syllable functions as a segmentation unit in speech processing. However, while French has relatively regular and clearly bounded syllables, other languages, such as English, do not. No trace of syllabifying segmentation was found in English listeners listening to English words, French words, or nonsense words. French listeners, however, showed evidence of syllabification even when they were listening to English words. We conclude that alternative segmentation routines are available to the human language processor. In some cases speech segmentation may involve the operation of more than one procedure.

Abstract

Recognizing spoken language involves automatic activation of multiple candidate words. The process of selection between candidates is made more efficient by inhibition of embedded words (like egg in beg) that leave a portion of the input stranded (here, b). Results from European languages suggest that this inhibition occurs when consonants are stranded but not when syllables are stranded. The reason why leftover syllables do not lead to inhibition could be that in principle they might themselves be words; in European languages, a syllable can be a word. In Sesotho (a Bantu language), however, a single syllable cannot be a word. We report that in Sesotho, word recognition is inhibited by stranded consonants, but stranded monosyllables produce no more difficulty than stranded bisyllables (which could be Sesotho words). This finding suggests that the viability constraint which inhibits spurious embedded word candidates is not sensitive to language-specific word structure, but is universal.

Abstract

Becoming a native listener is the necessary precursor to becoming a native speaker. Babies in the first year of life undertake a remarkable amount of work; by the time they begin to speak, they have perceptually mastered the phonological repertoire and phoneme co-occurrence probabilities of the native language, and they can locate familiar word-forms in novel continuous-speech contexts. The skills acquired at this early stage form a necessary part of adult listening. However, the same native listening skills also underlie problems in listening to a late-acquired non-native language, accounting for why in such a case listening (an innate ability) is sometimes paradoxically more difficult than, for instance, reading (a learned ability).

Abstract

In four experiments, we examined the facilitation that occurs when spoken-word targets rhyme with preceding spoken primes. In Experiment 1, listeners’ lexical decisions were faster to words following rhyming words (e.g., ramp–LAMP) than to words following unrelated primes (e.g., pink–LAMP). No facilitation was observed for nonword targets. Targets that almost rhymed with their primes (foils; e.g., bulk–SULSH) were included in Experiment 2; facilitation for rhyming targets was severely attenuated. Experiments 3 and 4 were single-word shadowing variants of the earlier experiments. There was facilitation for both rhyming words and nonwords; the presence of foils had no significant influence on the priming effect. A major component of the facilitation in lexical decision appears to be strategic: Listeners are biased to say “yes” to targets that rhyme with their primes, unless foils discourage this strategy. The nonstrategic component of phonological facilitation may reflect speech perception processes that operate prior to lexical access.

Abstract

Spoken word recognition involves automatic activation of lexical candidates compatible with the perceived input. In running speech, words abut one another without intervening gaps, and syllable boundaries can mismatch with word boundaries. For instance, liaison in ’petit agneau’ creates a syllable beginning with a consonant although ’agneau’ begins with a vowel. In two cross-modal priming experiments we investigate how French listeners recognise words in liaison environments. These results suggest that the resolution of liaison in part depends on acoustic cues which distinguish liaison from non-liaison consonants, and in part on the availability of lexical support for a liaison interpretation.

Abstract

Two experiments examined the nature of access, storage, and comprehension of idiomatic phrases. In both studies a Phrase Classification Task was utilized. In this, reaction times to determine whether or not word strings constituted acceptable English phrases were measured. Classification times were significantly faster to idiom than to matched control phrases. This effect held under conditions involving different categories of idioms, different transitional probabilities among words in the phrases, and different levels of awareness of the presence of idioms in the materials. The data support a Lexical Representation Hypothesis for the processing of idioms.