Publications

Abstract

Same-different discrimination judgments for pairs of Korean stop consonants, or of Japanese syllables differing in phonetic segment length, were made by adult Korean adoptees in the Netherlands, by matched Dutch controls, and Korean controls. The adoptees did not outdo either control group on either task, although the same individuals had performed significantly better than matched controls on an identification learning task. This suggests that early exposure to multiple phonetic systems does not specifically improve acoustic-phonetic skills; rather, enhanced performance suggests retained language knowledge.

Abstract

Orthographies encode phonological information only at the level of words (chiefly, the information encoded concerns phonetic segments; in some cases, tonal information or default stress may be encoded). Of primary interest to second language (L2) learners is whether orthography can assist in clarifying L2 phonological distinctions that are particularly difficult to perceive (e.g., where one native-language phonemic category captures two L2 categories). A review of spoken-word recognition evidence suggests that orthographic information can install knowledge of such a distinction in lexical representations but that this does not affect learners’ ability to perceive the phonemic distinction in speech. Words containing the difficult phonemes become even harder for L2 listeners to recognize, because perception maps less accurately to lexical content.

Abstract

In an auditory lexical decision experiment, 5,541 spoken content words and pseudo-words were presented to 20 native speakers of Dutch. The words vary in phonological makeup and in number of syllables and stress pattern, and are further representative of the native Dutch vocabulary in that most are morphologically complex, comprising two stems or one stem plus derivational and inflectional suffixes, with inflections representing both regular and irregular paradigms; the pseudo-words were matched in these respects to the real words. The BALDEY data file includes response times and accuracy rates, with for each item morphological information plus phonological and acoustic information derived from automatic phonemic segmentation of the stimuli. Two initial analyses illustrate how this data set can be used. First, we discuss several measures of the point at which a word has no further neighbors, and compare the degree to which each measure predicts our lexical decision response outcomes. Second, we investigate how well four different measures of frequency of occurrence (from written corpora, spoken corpora, subtitles and frequency ratings by 70 participants) predict the same outcomes. These analyses motivate general conclusions about the auditory lexical decision task. The (publicly available) BALDEY database lends itself to many further analyses.

Abstract

Vocabularies contain hundreds of thousands of words built from only a handful of phonemes, so that inevitably longer words tend to contain shorter ones. In many languages (but not all) such embedded words occur more often word-initially than word-finally, and this asymmetry, if present, has farreaching consequences for spoken-word recognition. Prior research had ascribed the asymmetry to suffixing or to effects of stress (in particular, final syllables containing the vowel schwa). Analyses of the standard French vocabulary here reveal an effect of suffixing, as predicted by this account, and further analyses of an artificial variety of French reveal that extensive final schwa has an independent and additive effect in promoting the embedding asymmetry.

Abstract

An audio and video corpus of speech addressed to 28 11-month-olds is described. The corpus allows comparisons between adult speech directed towards infants, familiar adults and unfamiliar adult addressees, as well as of caregivers’ word teaching strategies across word classes. Summary data show that infant-directed speech differed more from speech to unfamiliar than familiar adults; that word teaching strategies for nominals versus verbs and adjectives differed; that mothers mostly addressed infants with multi-word utterances; and that infants’ vocabulary size was unrelated to speech rate, but correlated positively with predominance of continuous caregiver speech (not of isolated words) in the input.

Abstract

The ability to extract word forms from continuous speech is a prerequisite for constructing a vocabulary and emerges in the first year of life. Electrophysiological (ERP) studies of speech segmentation by 9- to 12-month-old listeners in several languages have found a left-localized negativity linked to word onset as a marker of word detection. We report an ERP study showing significant evidence of speech segmentation in Dutch-learning 7-month-olds. In contrast to the left-localized negative effect reported with older infants, the observed overall mean effect had a positive polarity. Inspection of individual results revealed two participant sub-groups: a majority showing a positive-going response, and a minority showing the left negativity observed in older age groups. We retested participants at age three, on vocabulary comprehension and word and sentence production. On every test, children who at 7 months had shown the negativity associated with segmentation of words from speech outperformed those who had produced positive-going brain responses to the same input. The earlier that infants show the left-localized brain responses typically indicating detection of words in speech, the better their early childhood language skills.

Abstract

Analysis of a corpus of spontaneously produced Japanese puns from a single speaker over a two-year period provides a view of how a punster selects a source word for a pun and transforms it into another word for humorous effect. The pun-making process is driven by a principle of similarity: the source word should as far as possible be preserved (in terms of segmental sequence) in the pun. This renders homophones (English example: band–banned) the pun type of choice, with part–whole relationships of embedding (cap–capture), and mutations of the source word (peas–bees) rather less favored. Similarity also governs mutations in that single-phoneme substitutions outnumber larger changes, and in phoneme substitutions, subphonemic features tend to be preserved. The process of spontaneous punning thus applies, on line, the same similarity criteria as govern explicit similarity judgments and offline decisions about pun success (e.g., for inclusion in published collections). Finally, the process of spoken-word recognition is word-play-friendly in that it involves multiple word-form activation and competition, which, coupled with known techniques in use in difficult listening conditions, enables listeners to generate most pun types as offshoots of normal listening procedures.

Abstract

Listeners retune the boundaries between phonetic categories to adjust to individual speakers' productions. Lexical information, for example, indicates what an unusual sound is supposed to be, and boundary retuning then enables the speaker's sound to be included in the appropriate auditory phonetic category. In this study, it was investigated whether lexical knowledge that is known to guide the retuning of auditory phonetic categories, can also retune visual phonetic categories. In Experiment 1, exposure to a visual idiosyncrasy in ambiguous audiovisually presented target words in a lexical decision task indeed resulted in retuning of the visual category boundary based on the disambiguating lexical context. In Experiment 2 it was tested whether lexical information retunes visual categories directly, or indirectly through the generalization from retuned auditory phonetic categories. Here, participants were exposed to auditory-only versions of the same ambiguous target words as in Experiment 1. Auditory phonetic categories were retuned by lexical knowledge, but no shifts were observed for the visual phonetic categories. Lexical knowledge can therefore guide retuning of visual phonetic categories, but lexically guided retuning of auditory phonetic categories is not generalized to visual categories. Rather, listeners adjust auditory and visual phonetic categories to talker idiosyncrasies separately.

Abstract

Languages differ in the constitution of their phonemic repertoire and in the relative distinctiveness of phonemes within the repertoire. In the present study, we asked whether such differences constrain spoken-word recognition, via two word reconstruction experiments, in which listeners turned non-words into real words by changing single sounds. The experiments were carried out in Dutch (which has a relatively balanced vowel-consonant ratio and many similar vowels) and in Spanish (which has many more consonants than vowels and high distinctiveness among the vowels). Both Dutch and Spanish listeners responded significantly faster and more accurately when required to change vowels as opposed to consonants; when allowed to change any phoneme, they more often altered vowels than consonants. Vowel information thus appears to constrain lexical selection less tightly (allow more potential candidates) than does consonant information, independent of language-specific phoneme repertoire and of relative distinctiveness of vowels.

Abstract

Spraak is continu, er zijn geen betrouwbare signalen waardoor de luisteraar weet waar het ene woord eindigt en het volgende begint. Voor volwassen luisteraars is het segmenteren van gesproken taal in afzonderlijke woorden dus niet onproblematisch, maar voor een kind dat nog geen woordenschat bezit, vormt de continuïteit van spraak een nog grotere uitdaging. Desalniettemin produceren de meeste kinderen hun eerste herkenbare woorden rond het begin van het tweede levensjaar. Aan deze vroege spraakproducties gaat een formidabele perceptuele prestatie vooraf. Tijdens het eerste levensjaar - met name gedurende de tweede helft - ontwikkelt de spraakperceptie zich van een algemeen fonetisch discriminatievermogen tot een selectieve gevoeligheid voor de fonologische contrasten die in de moedertaal voorkomen. Recent onderzoek heeft verder aangetoond dat kinderen, lang voordat ze ook maar een enkel woord kunnen zeggen, in staat zijn woorden die kenmerkend zijn voor hun moedertaal te onderscheiden van woorden die dat niet zijn. Bovendien kunnen ze woorden die eerst in isolatie werden aangeboden herkennen in een continue spraakcontext. Het dagelijkse taalaanbod aan een kind van deze leeftijd maakt het in zekere zin niet gemakkelijk, bijvoorbeeld doordat de meeste woorden niet in isolatie voorkomen. Toch wordt het kind ook wel houvast geboden, onder andere doordat het woordgebruik beperkt is.

Abstract

Dutch listeners were slower to make judgements about the semantic relatedness between a spoken target word (e.g. atLEET, 'athlete') and a previously presented visual prime word (e.g. SPORT 'sport') when the spoken word was mis-stressed. The adverse effect of mis-stressing confirms the role of stress information in lexical recognition in Dutch. However, although the erroneous stress pattern was always initially compatible with a competing word (e.g. ATlas, 'atlas'), mis-stressed words did not produced high false alarm rates in unrelated pairs (e.g. SPORT - atLAS). This suggests that stress information did not completely rule out segmentally matching but suprasegmentally mismatching words, a finding consistent with spoken-word recognition models involving multiple activation and inter-word competition.

Abstract

Simulations explored the inability of the TRACE model of spoken-word recognition to model the effects on human listening of acoustic-phonetic mismatches in word forms. The source of TRACE's failure lay not in its interactive connectivity, not in the presence of interword competition, and not in the use of phonemic representations, but in the need for continuously optimised interpretation of the input. When an analogue of TRACE was allowed to cycle to asymptote on every slice of input, an acceptable simulation of the subcategorical mismatch data was achieved. Even then, however, the simulation was not as close as that produced by the Merge model.

Abstract

Dutch-learning and English-learning 9-month-olds were tested, using the Headturn Preference Procedure, for their ability to segment Dutch words with strong/weak stress patterns from fluent Dutch speech. This prosodic pattern is highly typical for words of both languages. The infants were familiarized with pairs of words and then tested on four passages, two that included the familiarized words and two that did not. Both the Dutch- and the English-learning infants gave evidence of segmenting the targets from the passages, to an equivalent degree. Thus, English-learning infants are able to extract words from fluent speech in a language that is phonetically different from English. We discuss the possibility that this cross-language segmentation ability is aided by the similarity of the typical rhythmic structure of Dutch and English words.

Abstract

Lexical knowledge influences how human listeners make decisions about speech sounds. Positive lexical effects (faster responses to target sounds in words than in nonwords) are robust across several laboratory tasks, while negative effects (slower responses to targets in more word-like nonwords than in less word-like nonwords) have been found in phonetic decision tasks but not phoneme monitoring tasks. The present experiments tested whether negative lexical effects are therefore a task-specific consequence of the forced choice required in phonetic decision. We compared phoneme monitoring and phonetic decision performance using the same Dutch materials in each task. In both experiments there were positive lexical effects, but no negative lexical effects. We observe that in all studies showing negative lexical effects, the materials were made by cross-splicing, which meant that they contained perceptual evidence supporting the lexically-consistent phonemes. Lexical knowledge seems to influence phonemic decision-making only when there is evidence for the lexically-consistent phoneme in the speech signal.

Abstract

We briefly describe the Merge model of phonemic decision-making, and, in the light of general arguments about the possible role of feedback in spoken-word recognition, defend Merge's feedforward structure. Merge not only accounts adequately for the data, without invoking feedback connections, but does so in a parsimonious manner.

Abstract

The central thesis of the target article was that feedback is never necessary in spoken word recognition. The commentaries present no new data and no new theoretical arguments which lead us to revise this position. In this response we begin by clarifying some terminological issues which have lead to a number of significant misunderstandings. We provide some new arguments to support our case that the feedforward model Merge is indeed more parsimonious than the interactive alternatives, and that it provides a more convincing account of the data than alternative models. Finally, we extend the arguments to deal with new issues raised by the commentators such as infant speech perception and neural architecture.

Abstract

Top-down feedback does not benefit speech recognition; on the contrary, it can hinder it. No experimental data imply that feedback loops are required for speech recognition. Feedback is accordingly unnecessary and spoken word recognition is modular. To defend this thesis, we analyse lexical involvement in phonemic decision making. TRACE (McClelland & Elman 1986), a model with feedback from the lexicon to prelexical processes, is unable to account for all the available data on phonemic decision making. The modular Race model (Cutler & Norris 1979) is likewise challenged by some recent results, however. We therefore present a new modular model of phonemic decision making, the Merge model. In Merge, information flows from prelexical processes to the lexicon without feedback. Because phonemic decisions are based on the merging of prelexical and lexical information, Merge correctly predicts lexical involvement in phonemic decisions in both words and nonwords. Computer simulations show how Merge is able to account for the data through a process of competition between lexical hypotheses. We discuss the issue of feedback in other areas of language processing and conclude that modular models are particularly well suited to the problems and constraints of speech recognition.

Abstract

Two word-spotting experiments are reported that examine whether the Possible-Word Constraint (PWC) [1] is a language-specific or language-universal strategy for the segmentation of continuous speech. The PWC disfavours parses which leave an impossible residue between the end of a candidate word and a known boundary. The experiments examined cases where the residue was either a CV syllable with a lax vowel, or a CVC syllable with a schwa. Although neither syllable context is a possible word in English, word-spotting in both contexts was easier than with a context consisting of a single consonant. The PWC appears to be language-universal rather than language-specific.

Abstract

Simulations explored the inability of the TRACE model of spoken-word recognition to model the effects on human listening of subcategorical mismatch in word forms. The source of TRACE's failure lay not in interactive connectivity, not in the presence of inter-word competition, and not in the use of phonemic representations, but in the need for continuously optimised interpretation of the input. When an analogue of TRACE was allowed to cycle to asymptote on every slice of input, an acceptable simulation of the subcategorical mismatch data was achieved. Even then, however, the simulation was not as close as that produced by the Merge model, which has inter-word competition, phonemic representations and continuous optimisation (but no interactive connectivity).

Abstract

A database is presented of relative familiarity ratings for 24 sets of Japanese words, each set comprising words overlapping in the initial portions. These ratings are useful for the generation of material sets for research in the recognition of spoken words.

Abstract

Clashen proposes two distinct processing routes, for regularly and irregularly inflected forms, respectively, and thus is apparently making a psychological claim. We argue his position, which embodies a strictly linguistic perspective, does not constitute a psychological processing model.

Abstract

Language production and comprehension are intimately interrelated; and models of production and comprehension should, we argue, be constrained by common architectural guidelines. Levelt et al.'s target article adopts as guiding principle Ockham's razor: the best model of production is the simplest one. We recommend adoption of the same principle in comprehension, with consequent simplification of some well-known types of models.

Abstract

Three experiments addressed the question of whether pitch-accent information may be exploited in the process of recognizing spoken words in Tokyo Japanese. In a two-choice classification task, listeners judged from which of two words, differing in accentual structure, isolated syllables had been extracted ~e.g., ka from baka HL or gaka LH!; most judgments were correct, and listeners’ decisions were correlated with the fundamental frequency characteristics of the syllables. In a gating experiment, listeners heard initial fragments of words and guessed what the words were; their guesses overwhelmingly had the same initial accent structure as the gated word even when only the beginning CV of the stimulus ~e.g., na- from nagasa HLL or nagashi LHH! was presented. In addition, listeners were more confident in guesses with the same initial accent structure as the stimulus than in guesses with different accent. In a lexical decision experiment, responses to spoken words ~e.g., ame HL! were speeded by previous presentation of the same word ~e.g., ame HL! but not by previous presentation of a word differing only in accent ~e.g., ame LH!. Together these findings provide strong evidence that accentual information constrains the activation and selection of candidates for spoken-word recognition.

Abstract

Two lexical decision studies examined the effects of single-phoneme mismatches on lexical activation in spoken-word recognition. One study was carried out in English, and involved spoken primes and visually presented lexical decision targets. The other study was carried out in Dutch, and primes and targets were both presented auditorily. Facilitation was found only for spoken targets preceded immediately by spoken primes; no facilitation occurred when targets were presented visually, or when intervening input occurred between prime and target. The effects of vowel mismatches and consonant mismatches were equivalent.

Abstract

In 5 experiments, listeners heard words and nonwords, some cross-spliced so that they contained acoustic-phonetic mismatches. Performance was worse on mismatching than on matching items. Words cross-spliced with words and words cross-spliced with nonwords produced parallel results. However, in lexical decision and 1 of 3 phonetic decision experiments, performance on nonwords cross-spliced with words was poorer than on nonwords cross-spliced with nonwords. A gating study confirmed that there were misleading coarticulatory cues in the cross-spliced items; a sixth experiment showed that the earlier results were not due to interitem differences in the strength of these cues. Three models of phonetic decision making (the Race model, the TRACE model, and a postlexical model) did not explain the data. A new bottom-up model is outlined that accounts for the findings in terms of lexical involvement at a dedicated decision-making stage.

Abstract

Two experiments examined the processing of Tokyo Japanese pitchaccent distinctions by native speakers of Japanese from two accentlessvariety areas. In both experiments, listeners were presented with Tokyo Japanese speech materials used in an earlier study with Tokyo Japanese listeners, who clearly exploited the pitch-accent information in spokenword recognition. In the "rst experiment, listeners judged from which of two words, di!ering in accentual structure, isolated syllables had been extracted. Both new groups were, overall, as successful at this task as Tokyo Japanese speakers had been, but their response patterns differed from those of the Tokyo Japanese, for instance in that a bias towards H judgments in the Tokyo Japanese responses was weakened in the present groups' responses. In a second experiment, listeners heard word fragments and guessed what the words were; in this task, the speakers from accentless areas again performed significantly above chance, but their responses showed less sensitivity to the information in the input, and greater bias towards vocabulary distribution frequencies, than had been observed with the Tokyo Japanese listeners. The results suggest that experience with a local accentless dialect affects the processing of accent for word recognition in Tokyo Japanese, even for listeners with extensive exposure to Tokyo Japanese.

Abstract

A corpus of digitized speech errors is used to compare the prosody of correction patterns for word-level vs. sound-level errors. Results for both peak F0 and perceived prosodic markedness confirm that speakers are more likely to mark corrections of word-level errors than corrections of sound-level errors, and that errors ambiguous between word-level and soundlevel (such as boat for moat) show correction patterns like those for sound level errors. This finding increases the plausibility of the claim that word-sound-ambiguous errors arise at the same level of processing as sound errors that do not form words.

Abstract

We report a series of experiments examining the effects on word processing of insertion of an optional epenthetic vowel in word-final consonant clusters in Dutch. Such epenthesis turns film, for instance, into film. In a word-reversal task listeners treated words with and without epenthesis alike, as monosyllables, suggesting that the variant forms both activate the same canonical representation, that of a monosyllabic word without epenthesis. In both lexical decision and word spotting, response times to recognize words were significantly faster when epenthesis was present than when the word was presented in its canonical form without epenthesis. It is argued that addition of the epenthetic vowel makes the liquid consonants constituting the first member of a cluster more perceptible; a final phoneme-detection experiment confirmed that this was the case. These findings show that a transformed variant of a word, although it contacts the lexicon via the representation of the canonical form, can be more easily perceptible than that canonical form.

Abstract

Recent research in speech production has shown that syntactic structure is reflected in segmental phonology--the application of certain phonological rules of English (e.g., palatalization and alveolar flapping) is inhibited across phrase boundaries. We examined whether such segmental effects can be used in speech perception as cues to syntactic structure, and the relation between the use of these segmental features as syntactic markers in production and perception. Speakers of American English (a dialect in which the above segmental effects occur) could indeed use the segmental cues in syntax perception; speakers of British English (in which the effects do not occur) were unable to make use of them, while speakers of British English who were long-term residents of the United States showed intermediate performance.