Publications

Abstract

Language evolution can be viewed from two viewpoints: the development of a communicative system and the biological adaptations necessary for producing and perceiving said system. The communicative-system vantage point has enjoyed a wealth of mathematical models based on simple distributional properties of language, often formulated as empirical laws. However, be- yond vague psychological notions of “least effort”, no principled explanation has been proposed for the existence and success of such laws. Meanwhile, psychological and neurobiological mod- els have focused largely on the computational constraints presented by incremental, real-time processing. In the following, we show that information-theoretic entropy underpins successful models of both types and provides a more principled motivation for Zipf’s Law

Abstract

Experiments in Artificial Language Learn-
ing have revealed much about the cogni-
tive mechanisms underlying sequence and
language learning in human adults, in in-
fants and in non-human animals. This pa-
per focuses on their ability to generalize
to novel grammatical instances (i.e., in-
stances consistent with a familiarization
pattern). Notably, the propensity to gen-
eralize appears to be negatively correlated
with the amount of exposure to the artifi-
cial language, a fact that has been claimed
to be contrary to the predictions of statis-
tical models (Pe
̃
na et al. (2002); Endress
and Bonatti (2007)). In this paper, we pro-
pose to model generalization as a three-
step process, and we demonstrate that the
use of statistical models for the first two
steps, contrary to widespread intuitions in
the ALL-field, can explain the observed
decrease of the propensity to generalize
with exposure time.

Abstract

In an influential paper, Marcus et al. [1999] claimed that connectionist models
cannot account for human success at learning tasks that involved generalization
of abstract knowledge such as grammatical rules. This claim triggered a heated
debate, centered mostly around variants of the Simple Recurrent Network model
[Elman, 1990]. In our work, we revisit this unresolved debate and analyze the
underlying issues from a different perspective. We argue that, in order to simulate
human-like learning of grammatical rules, a neural network model should not be
used as a
tabula rasa
, but rather, the initial wiring of the neural connections and
the experience acquired prior to the actual task should be incorporated into the
model. We present two methods that aim to provide such initial state: a manipu-
lation of the initial connections of the network in a cognitively plausible manner
(concretely, by implementing a “delay-line” memory), and a pre-training algorithm
that incrementally challenges the network with novel stimuli. We implement such
techniques in an Echo State Network [Jaeger, 2001], and we show that only when
combining both techniques the ESN is able to learn truly general identity rules.

Abstract

Speakers use differential referring expressions in pragmatically appropriate ways to produce coherent narratives. Languages, however, differ in a) whether REs as arguments can be dropped and b) whether personal pronouns encode gender. We examine two languages that differ from each other in these two aspects and ask whether the co-reference context and the gender encoding options affect the use of REs differentially. We elicited narratives from Dutch and Turkish speakers about two types of three-person events, one including people of the same and the other of mixed-gender. Speakers re-introduced referents into the discourse with fuller forms (NPs) and maintained them with reduced forms (overt or null pronoun). Turkish speakers used pronouns mainly to mark emphasis and only Dutch speakers used pronouns differentially across the two types of videos. We argue that linguistic possibilities available in languages tune speakers into taking different principles into account to produce pragmatically coherent narratives

Abstract

Lexical statistics and a production experiment are used to gauge the extent to which the linguistic notion of morphological productivity is relevant for psycholinguistic theories of speech production in languages such as Dutch and English. Lexical statistics of productivity show that despite the relatively poor morphology of Dutch, new words are created often enough for the marginalisation of word formation in theories of speech production to be theoretically unattractive. This conclusion is supported by the results of a production experiment in which subjects freely created hundreds of productive, but only a handful of unproductive, neologisms. A tentative solution is proposed as to why the opposite pattern has been observed in the speech of jargonaphasics.

Abstract

The Headturn Preference Procedure (HPP) is a frequently used method (e.g., Jusczyk & Aslin; and subsequent studies) to investigate linguistic abilities in infants. In this paradigm infants are usually first familiarised with words and then tested for a listening preference for passages containing those words in comparison to unrelated passages. Listening preference is defined as the time an infant spends attending to those passages with his or her head turned towards a flashing light and the speech stimuli. The knowledge and abilities inferred from the results of HPP studies have been used to reason about and formally model early linguistic skills and language acquisition. However, the actual cause of infants' behaviour in HPP experiments has been subject to numerous assumptions as there are no means to directly tap into cognitive processes. To make these assumptions explicit, and more crucially, to understand how infants' behaviour emerges if only general learning mechanisms are assumed, we introduce a computational model of the HPP. Simulations with the computational HPP model show that the difference in infant behaviour between familiarised and unfamiliar words in passages can be explained by a general learning mechanism and that many assumptions underlying the HPP are not necessarily warranted. We discuss the implications for conventional interpretations of the outcomes of HPP experiments.

Abstract

How does a naive language learner deal with speaker variation irrelevant to distinguishing word meanings? Experimental data is contradictory, and incompatible models have been proposed. Here, we examine basic assumptions regarding the acoustic signal the learner deals with: Is speaker variability a hurdle in discriminating sounds or can it easily be ignored? To this end, we summarize existing infant data. We then present machine-based discriminability scores of sound pairs obtained without any language knowledge. Our results show that speaker variability decreases sound contrast discriminability, and that some contrasts are affected more than others. However, chance performance is rare; most contrasts remain discriminable in the face of speaker variation. We take our results to mean that speaker variation is not a uniform hurdle to discriminating sound contrasts, and careful examination is necessary when planning and interpreting studies testing whether and to what extent infants (and adults) are sensitive to speaker differences.

Abstract

During conversation, spoken utterances occur in rich acoustic contexts, including speech produced by our interlocutor(s) and speech we produced ourselves. Prosodic characteristics of the acoustic context have been known to influence speech perception in a contrastive fashion: for instance, a vowel presented in a fast context is perceived to have a longer duration than the same vowel in a slow context. Given the ubiquity of the sound of our own voice, it may be that our own speech rate - a common source of acoustic context - also influences our perception of the speech of others. Two experiments were designed to test this hypothesis. Experiment 1 replicated earlier contextual rate effects by showing that hearing pre-recorded fast or slow context sentences alters the perception of ambiguous Dutch target words. Experiment 2 then extended this finding by showing that talking at a fast or slow rate prior to the presentation of the target words also altered the perception of those words. These results suggest that between-talker variation in speech rate production may induce between-talker variation in speech perception, thus potentially explaining why interlocutors tend to converge on speech rate in dialogue settings.

Abstract

The notion of relational grammar is extented to ternary relations and illustrated by a fragment of English. Some of Peirce's terms for ternary relations are shown to be incorrect and corrected.

Abstract

(From the chapter) the first section considers very briefly the kinds of processes that can be inferred to underlie errors that do not set in until after a period of correct usage acquisition often seems to be a more extended process than we have envisioned summarize a currently influential model of how linguistic forms, meaning, and communication are interrelated in the acquisition of language, point out some challenging problems for this model, and suggest that the notion of "meaning" in language must be reconceptualized before we can hope to solve these problems evidence from several types of late errors is marshalled in support of these arguments (From the preface) provides many examples of new errors that children introduce at relatively advanced stages of mastery of semantics and syntax Bowerman views these seemingly backwards steps as indications of definite steps forward by the child achieving reflective, flexible and integrated systems of semantics and syntax (

Abstract

Narrow focus refers to accent placement that forces one interpretation of a sentence, which is then often perceived contrastively. Narrow focus is formalised in terms of alternative sets, i.e. contextually or situationally salient alternatives. In this paper, we investigate whether this model is valid also in human utterance processing. We present an eye-tracking experiment to study listeners’ expectations (i.e. eye-movements) with respect to upcoming referents. Some of the objects contrast in colour with objects that were previously referred to, others do not; the objects are referred to with either a narrow focus on the colour adjective or with broad focus on the noun. Results show that narrow focus on the adjective increases early fixations to contrastive referents. Narrow focus hence activates alternative referents in human utterance processing

Abstract

This is an encyclopedia entry surveying research and theoretical approaches to politeness phenomena in language usage.

Abstract

The systematic study of kinesics, gaze, and gestural aspects of communication in Central American cultures is a recent phenomenon, most of it focussing on the Mayan cultures of southern Mexico, Guatemala, and Belize. This article surveys ethnographic observations and research reports on bodily aspects of speaking in three domains: gaze and kinesics in social interaction, indexical pointing in adult and caregiver-child interactions, and co-speech gestures associated with “absolute” (geographically-based) systems of spatial reference. In addition, it reports how the indigenous co-speech gesture repertoire has provided the basis for developing village sign languages in the region. It is argued that studies of the embodied aspects of speech in the Mayan areas of Mexico and Central America have contributed to the typology of gestures and of spatial frames of reference. They have refined our understanding of how spatial frames of reference are invoked, communicated, and switched in conversational interaction and of the importance of co-speech gestures in understanding language use, language acquisition, and the transmission of culture-specific cognitive styles.

Abstract

How do children isolate the semantic package contained in verb roots in the Mayan language Tzeltal? One might imagine that the canonical CVC shape of roots characteristic of Mayan languages would make the job simple, but the root is normally preceded and followed by affixes which mask its identity. Pye (1983) demonstrated that, in Kiche' Mayan, prosodic salience overrides semantic salience, and children's first words in Kiche' are often composed of only the final (stressed) syllable constituted by the final consonant of the CVC root and a 'meaningless' termination suffix. Intonation thus plays a crucial role in early Kiche' morphological development. Tzeltal presents a rather different picture: The first words of children around the age of 1;6 are bare roots, children strip off all prefixes and suffixes which are obligatory in adult speech. They gradually add them, starting with the suffixes (which receive the main stress), but person prefixes are omitted in some contexts past a child's third birthday, and one obligatory aspectual prefix (x-) is systematically omitted by the four children in my longitudinal study even after they are four years old. Tzeltal children's first verbs generally show faultless isolation of the root. An account in terms of intonation or stress cannot explain this ability (the prefixes are not all syllables; the roots are not always stressed). This paper suggests that probable clues include the fact that the CVC root stays constant across contexts (with some exceptions) whereas the affixes vary, that there are some linguistic contexts where the root occurs without any prefixes (relatively frequent in the input), and that the Tzeltal discourse convention of responding by repeating with appropriate deictic alternation (e.g., "I see it." "Oh, you see it.") highlights the root.

Abstract

This paper addresses the theories of Eve Clark about how children learn word meanings in western middle-class interactional contexts by examining child language data from a Tzeltal Maya society in southern Mexico where interaction patterns are radically different. Through examples of caregiver interactions with children 12-30 months old, I ask what lessons we can learn from how the details of these interactions unfold in this non-child-centered cultural context, and specifically, what aspects of the Tzeltal linguistic and interactional context might help to focus children’s attention on the meanings and the conventional forms of words being used around them.

Abstract

A key part of learning to speak with others is figuring out when to start talking and how to hold the floor in conversation. For young children, the challenge of planning a linguistic response can slow down their response latencies, making misunderstanding, repair, and loss of the floor more likely. Like adults, children can mitigate their delays by using fillers (e.g., uh and um) at the start of their turns. In this chapter I analyze the onset and development of fillers in five children’s spontaneous speech from ages 1;6–3;6. My findings suggest that children start using fillers by 2;0, and use them to effectively mitigate delay in making a response.

Abstract

Conversation is a structured, joint action for which children need to learn a specialized set skills and conventions. Because conversation is a primary source of linguistic input, we can better grasp how children become active agents in their own linguistic development by studying their acquisition of conversational skills. In this chapter I review research on children’s turn-taking. This fundamental skill of human interaction allows children to gain feedback, make clarifications, and test hypotheses at every stage of development. I broadly review children’s conversational experiences, the types of turn-based contingency they must acquire, how they ask and answer questions, and when they manage to make timely responses

Abstract

Sentence production is the process we use to create language-specific sentences that convey particular meanings. In production, there are complex interactions between meaning, words, and syntax at different points in sentences. Computational models can make these interactions explicit and connectionist learning algorithms have been useful for building such models. Connectionist models use domaingeneral mechanisms to learn internal representations and these mechanisms can also explain evidence of long-term syntactic adaptation in adult speakers. This paper will review work showing that these models can generalize words in novel ways and learn typologically-different languages like English and Japanese. It will also present modeling work which shows that connectionist learning algorithms can account for complex sentence production in children and adult production phenomena like structural priming, heavy NP shift, and conceptual/lexical accessibility.

Abstract

The present study set out to pin down the role of four pitch accents, fall (H*L), rise-fall (L*HL), rise (L*H), fall-rise (H*LH), as well as deaccentuation, in interpreting new vs. given information in British English by the eyetracking paradigm. The pitch accents in question were claimed to convey information status in theories of English intonational meaning. There is, however, no consensus on the postulated roles of these pitch accents. Results clearly show that pitch accent type can and does matter when interpreting information status. The effects can be reflected in the mean proportions of fixations to the competitor in a selected time window. These patterns are also present in proportions of fixations to the target but to a lesser extent. Interestingly, the effects of pitch accent types are also reflected in how fast the participants could adjust their decision as to which picture to move before the name of the picture was fully revealed. For example, when the competitor was a given entity, the proportion of fixations to the competitor increased initially in most accent conditions in the first as a result of subjects' bias towards a given entity, but started to decrease substantially earlier in the H*L condition than in the L*H and deaccentuation conditions.

Abstract

This study investigates how Mandarin-speaking children interpret state-change verbs. In Mandarin, state-change is typically encoded with resultative verb compounds (RVCs), in which the first verb (V1) specifies an action and the second (V2) a result, for example, zhai-xia 'pick-descend' (= pick, pick off/down). Unlike English state-change verb such as pick, smash, mix and fill, the action verb (V1) may imply a state-change but it does not entail it; the state-change is specified by the additional result verb (V2). Previous studies have shown that children learning English and German tend to neglect the state-change meaning in monomorphemic state-change verbs like mix and fill (Gentner, 1978; Gropen et al, 1991) and verb-particle constructions like abplücken 'pick off' (Wittek, 1999, 2000) - they do not realize that this meaning is entailed. This study examines how Mandarin-speaking children interpret resultative verb compounds and the first verb of an RVC. Four groups of Mandarin-speaking children (mean ages 2;6, 3;6, 4;6, 6;1) and an adult group participated in a judgment task. The results show that Mandarin-speaking children know from a very young age that RVCs entail a state-change; ironically, however, they make a mistake that is just the opposite to that made by the learners of English and German: they often incorrectly interpret the action verb (V1) of an RVC as if it, in itself, also entails a state-change, even though it does not. This result suggests that children do not have a uniform strategy for interpreting verb meaning, but are influenced by the language-specific lexicalization patterns they encounter in their language.

Abstract

Previous work based on different groups of children has shown that four- to five-year-old children are similar to adults in both producing and comprehending the focus-toaccentuation mapping in Dutch, contra the alleged productionprecedes- comprehension asymmetry in earlier studies. In the current study, we addressed the question of whether there are individual differences in the production-comprehension (a)symmetricity. To this end, we examined the use of prosody in focus marking in production and the processing of focusrelated prosody in online language comprehension in the same group of 4- to 5-year-olds. We have found that the relationship between comprehension and production can be rather diverse at an individual level. This result suggests some degree of independence in learning to use prosody to mark focus in production and learning to process focus-related prosodic information in online language comprehension, and implies influences of other linguistic and non-linguistic factors on the production-comprehension (a)symmetricity

Abstract

Despite of the different functions of pitch in tone and nontone languages, rises and falls are common pitch patterns across different languages. In the current study, we ask what is the language specific phonetic realization of rises and falls. Chinese and Dutch speakers participated in a production experiment. We used contexts composed for conveying specific communicative purposes to elicit rises and falls. We measured both tonal alignment and tonal scaling for both patterns. For the alignment measurements, we found language specific patterns for the rises, but for falls. For rises, both peak and valley were aligned later among Chinese speakers compared to Dutch speakers. For all the scaling measurements (maximum pitch, minimum pitch, and pitch range), no language specific patterns were found for either the rises or the falls

Abstract

“Gesture-first” theories dismiss ancestral great apes’ vocalization as a substrate for language evolution based on the claim that extant apes exhibit minimal learning and volitional control of vocalization. Contrary to this claim, we present data of novel learned and voluntarily controlled vocal behaviors produced by a human-fostered gorilla (G. gorilla gorilla). These behaviors demonstrate varying degrees of flexibility in the vocal apparatus (including diaphragm, lungs, larynx, and supralaryngeal articulators), and are predominantly performed in coordination with manual behaviors and gestures. Instead of a gesture-first theory, we suggest that these findings support multimodal theories of language evolution in which vocal and gestural forms are coordinated and supplement one another

Abstract

This paper discusses some improvements in recent and planned versions of the multimodal annotation tool ELAN, which are targeted at improving the usability of annotated files. Increased support for multilingual documents is provided, by allowing for multilingual vocabularies and by specifying a language per document, annotation layer (tier) or annotation. In addition, improvements in the search possibilities and the display of the results have been implemented, which are especially relevant in the interpretation of the results of complex multi-tier searches.

Abstract

Collocations generated by concordancers are a standard instrument in the exploitation of text corpora for the analysis of language use. Multimodal corpora show similar types of patterns, activities that frequently occur together, but there is no tool that offers facilities for visualising such patterns. Examples include timing of eye contact with respect to speech, and the alignment of activities of the two hands in signed languages. This paper describes recent enhancements to the standard CLARIN tools ELAN and TROVA for multimodal annotation to address these needs: first of all the query and concordancing functions were improved, and secondly the tools now generate visualisations of multilayer collocations that allow for intuitive explorations and analyses of multimodal data. This will provide a boost to the linguistic fields of gesture and sign language studies, as it will improve the exploitation of multimodal corpora.

Abstract

Although people are poor at naming odors, naming a smell helps to remember that odor. Previous studies show wine experts have better memory for smells, and they also name smells differently than novices. Is wine experts’ odor memory is verbally mediated? And is the odor memory advantage that experts have over novices restricted to odors in their domain of expertise, or does it generalize? Twenty-four wine experts and 24 novices smelled wines, wine-related odors and common odors, and remembered these. Half the participants also named the smells. Wine experts had better memory for wines, but not for the other odors, indicating their memory advantage is restricted to wine. Wine experts named odors better than novices, but there was no relationship between experts’ ability to name odors and their memory for odors. This suggests experts’ odor memory advantage is not linguistically mediated, but may be the result of differential perceptual learning

Abstract

The lexicon, considered as a component of the process of recognizing speech, is a device that accepts a sound image as input and outputs meaning. Lexical access is the process of formulating an appropriate input and mapping it onto an entry in the lexicon's store of sound images matched with their meanings. This chapter addresses the problems of auditory lexical access from continuous speech. The central argument to be proposed is that utterance prosody plays a crucial role in the access process. Continuous listening faces problems that are not present in visual recognition (reading) or in noncontinuous recognition (understanding isolated words). Aspects of utterance prosody offer a solution to these particular problems.

Abstract

To examine the relative roles of language-specific and language-universal mechanisms in the production of prosodic focus, we compared production of five different types of focus by native speakers of English and Mandarin. Two comparable dialogues were constructed for each language, with the same words appearing in focused and unfocused position; 24 speakers recorded each dialogue in each language. Duration, F0 (mean, maximum, range), and rms-intensity (mean, maximum) of all critical word tokens were measured. Across the different types of focus, cross-language differences were observed in the degree to which English versus Mandarin speakers use the different prosodic parameters to mark focus, suggesting that while prosody may be universally available for expressing focus, the means of its employment may be considerably language-specific

Abstract

Speech signals originate as a sequence of linguistic units selected by speakers, but these units are necessarily realised in the suprasegmental dimensions of time, frequency and amplitude. For this reason prosodic structure has been viewed as a mandatory target of language processing by both speakers and listeners. In apparent contradiction, however, prosody has also been argued to be ancillary rather than core linguistic structure, making processing of prosodic structure essentially optional. In the present tribute to one of the luminaries of prosodic research for the past quarter century, we review evidence from studies of the processing of lexical stress and focal accent which reconciles these views and shows that both claims are, each in their own way, fully true.

Abstract

One of a listener's major tasks in understanding continuous speech is segmenting the speech signal into separate words. When listening conditions are difficult, speakers can help listeners by deliberately speaking more clearly. In three experiments, we examined how word boundaries are produced in deliberately clear speech. We found that speakers do indeed attempt to mark word boundaries; moreover, they differentiate between word boundaries in a way which suggests they are sensitive to listener needs. Application of heuristic segmentation strategies makes word boundaries before strong syllables easiest for listeners to perceive; but under difficult listening conditions speakers pay more attention to marking word boundaries before weak syllables, i.e. they mark those boundaries which are otherwise particularly hard to perceive.

Abstract

Recently, there has been an explosion in the availability of large, good-quality cross-linguistic databases such as WALS (Dryer & Haspelmath, 2013), Glottolog (Hammarstrom et al., 2015) and Phoible (Moran & McCloy, 2014). Databases such as Phoible contain the actual segments used by various languages as they are given in the primary language descriptions. However, this segment-level representation cannot be used directly for analyses that require generalizations over classes of segments that share theoretically interesting features. Here we present a method and the associated R (R Core Team, 2014) code that allows the exible denition of such meaningful classes and that can identify the sets of segments falling into such a class for any language inventory. The method and its results are important for those interested in exploring cross-linguistic patterns of phonetic and phonological diversity and their relationship to extra-linguistic factors and processes such as climate, economics, history or human genetics.

Abstract

The current paper presents results for data on click learning obtained from a larger imaging study (using MRI and 3D intraoral scanning) designed to quantify and characterize intra- and inter-population variation of vocal tract structures and the relation of this to speech production. The aim of the click study was to ascertain whether and to what extent vocal tract morphology influences (1) the ability to learn to produce clicks and (2) the productions of those that successfully learn to produce these sounds. The results indicate that the presence of an alveolar ridge certainly does not prevent an individual from learning to produce click sounds (1). However, the subtle details of how clicks are produced may indeed be driven by palate shape (2).

Abstract

This article surveys what is currently known about the complex interplay between genetics and the language sciences. It focuses not only on the genetic architecture of language and speech, but also on their interactions on the cultural and evolutionary timescales. Given the complexity of these issues and their current state of flux and high dynamism, this article surveys the main findings and topics of interest while also briefly introducing the main relevant methods, thus allowing the interested reader to fully appreciate and understand them in their proper context. Of course, not all the relevant publications and resources are mentioned, but this article aims to select the most relevant, promising, or accessible for nonspecialists.

Abstract

Under what circumstances do languages die? Why has their “mortality rate” increased dramatically in the recent past? What “causes of death” can be identified for historical cases, to what extent are these generalizable, and how can they be captured in an explanatory theory? In pursuing these questions, it becomes apparent that in typical cases of language death various causes tend to interact in multiple ways. Speakers’ attitudes towards their language play a critical role in all of this. Existing categorial taxonomies do not succeed in modeling the complex relationships between these factors. Therefore, an alternative, dimensional approach is called for to more adequately address (and counter) the causes of language death in a given scenario.

Abstract

Numerous experiments show that space and musical pitch are
closely linked in people's minds. However, the exact nature of
space-pitch associations and their neuronal underpinnings are
not well understood. In an fMRI experiment we investigated
different types of spatial representations that may underlie
musical pitch. Participants judged stimuli that varied in
spatial height in both the visual and tactile modalities, as well
as auditory stimuli that varied in pitch height. In order to
distinguish between unimodal and multimodal spatial bases of
musical pitch, we examined whether pitch activations were
present in modality-specific (visual or tactile) versus
multimodal (visual and tactile) regions active during spatial
height processing. Judgments of musical pitch were found to
activate unimodal visual areas, suggesting that space-pitch
associations may involve modality-specific spatial
representations, supporting a key assumption of embodied
theories of metaphorical mental representation.

Abstract

Abstract mental representation is fundamental for human cognition. Forming such representations in time, especially from dynamic and noisy perceptual input, is a challenge for any processing modality, but perhaps none so acutely as for language processing. We show that LISA (Hummel & Holyaok, 1997) and DORA (Doumas, Hummel, & Sandhofer, 2008), models built to process and to learn structured (i.e., symbolic) rep resentations of conceptual properties and relations from unstructured inputs, show oscillatory activation during processing that is highly similar to the cortical activity elicited by the linguistic stimuli from Ding et al.(2016). We argue, as Ding et al.(2016), that this activation reflects formation of hierarchical linguistic representation, and furthermore, that the kind of computational mechanisms in LISA/DORA (e.g., temporal binding by systematic asynchrony of firing) may underlie formation of abstract linguistic representations in the human brain. It may be this repurposing that allowed for the generation or mergence of hierarchical linguistic structure, and therefore, human language, from extant cognitive and neural systems. We conclude that models of thinking and reasoning and models of language processing must be integrated —not only for increased plausiblity, but in order to advance both fields towards a larger integrative model of human cognition

Abstract

Previous studies have demonstrated that native listeners
modify their interpretation of a speech sound when a talker
produces an ambiguous sound in order to quickly tune into a
speaker, but there is hardly any evidence that non-native
listeners employ a similar mechanism when encountering
ambiguous pronunciations. So far, one study demonstrated
this lexically-guided perceptual learning effect for nonnatives,
using phoneme categories similar in the native
language of the listeners and the non-native language of the
stimulus materials. The present study investigates the question
whether phoneme category retuning is possible in a nonnative
language for a contrast, /l/-/r/, which is phonetically
differently embedded in the native (Dutch) and nonnative
(English) languages involved. Listening experiments indeed
showed a lexically-guided perceptual learning effect.
Assuming that Dutch listeners have different phoneme
categories for the native Dutch and non-native English /r/, as
marked differences between the languages exist for /r/, these
results, for the first time, seem to suggest that listeners are not
only able to retune their native phoneme categories but also
their non-native phoneme categories to include ambiguous
pronunciations.

Abstract

Listeners use their lexical knowledge to interpret ambiguous sounds, and retune their phonetic categories to include this ambiguous sound. Although there is ample evidence for lexically-guided retuning, the adaptation process is not fully understood. Using a lexical decision task with an embedded auditory semantic priming task, the present study investigates whether words containing an ambiguous sound are processed in the same way as “natural” words and whether adaptation to the ambiguous sound tends to equalize the processing of “ambiguous” and natural words. Analyses of the yes/no responses and reaction times to natural and “ambiguous” words showed that words containing an ambiguous sound were accepted as words less often and were processed slower than the same words without ambiguity. The difference in acceptance disappeared after exposure to approximately 15 ambiguous items. Interestingly, lower acceptance rates and slower processing did not have an effect on the processing of semantic information of the following word. However, lower acceptance rates of ambiguous primes predict slower reaction times of these primes, suggesting an important role of stimulus-specific characteristics in triggering lexically-guided perceptual learning.