Janet F. Werker

Janet F. Werker
University of British Columbia | UBC ·  Department of Psychology

PhD

About

256
Publications
104,372
Reads
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26,427
Citations
Additional affiliations
July 1994 - present
University of British Columbia
Position
  • Professor (Full)

Publications

Publications (256)
Poster
Full-text available
Background/Theory Tested: This study investigates the auditory processing abilities of 10-12 month-old English monolingual infants, specifically their ability to detect pitch changes in both music and speech. Previous research has shown that 6-month-old Japanese infants can detect pitch changes in Japanese speech but not in music, while 10-month-ol...
Poster
This research investigates the auditory processing of pitch contour in music and speech among 10-12 month-old English-learning infants. Utilizing a habituation-switch paradigm, infants were exposed to five-note melodies and five-syllable Japanese non-words to assess their sensitivity to pitch changes. Our primary hypothesis predicted that infants w...
Article
Full-text available
Growing evidence is demonstrating the connection between the microbiota gut-brain axis and neurodevelopment. Microbiota colonization occurs before the maturation of many neural systems and is linked to brain health. Because of this it has been hypothesized that the early microbiome interactions along the gut-brain axis evolved to promote advanced c...
Article
The perceptual system for speech is highly organized from early infancy. This organization bootstraps young human learners' ability to acquire their native speech and language from speech input. Here, we review behavioral and neuroimaging evidence that perceptual systems beyond the auditory modality are also specialized for speech in infancy, and t...
Article
Full-text available
Young infants are attuned to the indexical properties of speech: they can recognize highly familiar voices and distinguish them from unfamiliar voices. Less is known about how and when infants start to recognize unfamiliar voices, and to map them to faces. This skill is particularly challenging when portions of the speaker’s face are occluded, as i...
Article
Full-text available
A key question in studies of cognitive development is whether bilingual environments impact higher-cognitive functions. Inconclusive evidence in search of a “bilingual cognitive advantage” has sparked debates on the reliability of these findings. Few studies with infants have examined this question, but most of them include small samples. The curre...
Article
A growing body of work suggests that speaker-race influences how infants and toddlers interpret the meanings of words. In two experiments, we explored the role of speaker-race on whether newly learned word-object pairs are generalized to new speakers. Seventy-two 20-month-olds were taught two word-object pairs from a familiar race speaker, and two...
Article
The Annual Review of Developmental Psychology presents a conversation with Professor Sir Michael Rutter, held remotely in the time of COVID but nonetheless wonderfully revealing of who this incredible scholar is and how he thinks. The contributions he has made to our understanding of child development are so vast and varied as to almost defy descri...
Preprint
Full-text available
A bstract Infants start developing rudimentary language skills and can start understanding simple words well before their first birthday [Bergelson and Swingley, 2012]. This development has also been shown primarily using Event Related Potential (ERP) techniques to find evidence of word comprehension in the infant brain [Parise and Csibra, 2012, Fr...
Article
No PDF available ABSTRACT The speech that infants perceive and learn from is highly multisensory. Preverbal infants show multisensory speech sensitivities prior to direct associative experience, for instance, even to non-native speech that they have not experienced before. Sensorimotor influences on auditory perception are of increasing interest in...
Article
Full-text available
A bilingual environment is associated with changes in the brain's structure and function. Some suggest that bilingualism also improves higher-cognitive functions in infants as young as 6-months, yet whether this effect is associated with changes in the infant brain remains unknown. In the present study, we measured brain activity using functional n...
Article
Previous work indicates mutual exclusivity in word learning in monolingual, but not bilingual toddlers. We asked whether this difference indicates distinct conceptual biases, or instead reflects best-guess heuristic use in the absence of context. We altered word-learning contexts by manipulating whether a familiar- or unfamiliar-race speaker introd...
Article
The ability to identify individuals by voice is fundamental for communication. However, little is known about the expectations that infants hold when learning unfamiliar voices. Here, the voice‐learning skills of 4‐ and 8‐month‐olds (N = 53; 29 girls, 14 boys of various ethnicities) were tested using a preferential‐looking task that involved audiov...
Article
Full-text available
Significance In the adult brain, multimodal speech perception that interfaces with a bidirectional interaction of perception and production speech systems is increasingly accepted. Speech perception in infancy is already highly multisensory, suggesting an early emerging representation for speech across sensory modalities. We provide electrophysiolo...
Article
Perceptual attunement to the native phonetic repertoire occurs over the first year of life: an infant's discrimination of non-native phonetic contrasts declines while their discrimination of native phonetic contrasts improves, with the timing of change consistent with sensitive periods. The statistics of speech sound distributions is one source of...
Article
Full-text available
Three experiments examined the role of audiovisual speech on 24-month-old monolingual and bilinguals’ performance in a fast-mapping task. In all three experiments, toddlers were exposed to familiar trials which tested their knowledge of known word–referent pairs, disambiguation trials in which novel word–referent pairs were indirectly learned, and...
Article
Full-text available
From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) compared with adult-directed speech (ADS). Yet IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multisite study used the diversity of bilingual infant experiences to...
Article
The discovery of words in continuous speech is one of the first challenges faced by infants during language acquisition. This process is partially facilitated by statistical learning, the ability to discover and encode relevant patterns in the environment. Here, we used an electroencephalogram (EEG) index of neural entrainment to track 6-month-olds...
Preprint
The ability to identify individuals by voice is a fundamental communicative ability. However, little is known about the expectations that infants hold when learning the voices of unfamiliar people. Here, the voice-learning skills of 4- and 8-month-old infants (N=53) were tested using a preferential looking task that involved audio-visual stimuli of...
Article
Full-text available
Brain plasticity is dynamically regulated across the life span, peaking during windows of early life. Typically assessed in the physiological range of milliseconds (real time), these trajectories are also influenced on the longer timescales of developmental time (nurture) and evolutionary time (nature), which shape neural architectures that support...
Preprint
The first steps toward bilingual language acquisition have already begun at birth. When tested on their preference for English versus Tagalog, newborns whose mothers spoke only English during pregnancy showed a robust preference for English. In contrast, newborns whose mothers spoke both English and Tagalog regularly during pregnancy showed equal p...
Article
Significance The perceptual validity of synesthesia has been established by behavioral and neuroimaging evidence; however, its developmental origins remain unclear. Here we tested the hypothesis that synesthesia arises when there is less experience-dependent pruning during development. We did so by comparing adults with and without synesthesia on a...
Article
Full-text available
Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant...
Preprint
Full-text available
From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) than adult-directed speech (ADS). Yet, IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multi-site study used the diversity of bilingual infant experiences to explor...
Preprint
The discovery of words in continuous speech is one of the first challenges faced by infants during language acquisition. This process is partially facilitated by statistical learning, the ability to discover and encode relevant patterns in the environment. Here, we used an EEG index of neural entrainment in 6-month-olds (n=25) to track their segmen...
Article
Full-text available
The input contains perceptually available cues, which might allow young infants to discover abstract properties of the target language. Thus, word frequency and prosodic prominence correlate systematically with basic word order in natural languages. Prelexical infants are sensitive to these frequency-based and prosodic cues, and use them to parse n...
Article
Full-text available
The acoustic realization of phrasal prominence is proposed to correlate with the order of V(erbs) and O(bjects) in natural languages. The present production study with 15 talkers of Japanese (OV) and English (VO) investigates whether the speech signal contains coverbal visual information that covaries with auditory prosody, in Infant- and Adult-Dir...
Article
Full-text available
Background Prenatal maternal depression (PMD) and selective serotonin reuptake inhibitor (SSRI) antidepressants are associated with increased developmental risk in infants. Reports suggest that PMD is associated with hyperconnectivity of the insula and the amygdala, while SSRI exposure is associated with hyperconnectivity of the auditory network in...
Article
Research demonstrates that young infants attend to the indexical characteristics of speakers, including age, gender, and ethnicity, and that the relationship between language and ethnicity is intuitive among older children. However, little research has examined whether infants, within the first year, are sensitive to the co‐occurrences of ethnicity...
Article
Full-text available
The audiovisual speech signal contains multimodal information to phrase boundaries. In three artificial language learning studies with 12 groups of adult participants we investigated whether English monolinguals and bilingual speakers of English and a language with opposite basic word order (i.e., in which objects precede verbs) can use word freque...
Article
The relationship between speech perception and production is central to understanding language processing, yet remains under debate, particularly in early development. Recent research suggests that in infants aged 6 months, when the native phonological system is still being established, sensorimotor information from the articulators influences spee...
Article
Background: Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression during pregnancy. SSRIs cross the placenta, inhibit serotonin reuptake, and thereby are thought to alter central fetal serotonin signaling. Both prenatal maternal mood disturbances and in utero SSRI exposure have been associated with altered fetal and...
Article
Speech perception, word learning, and language acquisition in infancy: The voyage continues - Volume 39 Issue 4 - Janet F. WERKER
Article
In this article, I present a selective review of research on speech perception development and its relation to reference, word learning, and other aspects of language acquisition, focusing on the empirical and theoretical contributions that have come from my laboratory over the years. Discussed are the biases infants have at birth for processing sp...
Article
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Article
Mayberry and Kluender (2017) present an important and compelling argument that in order to understand critical periods (CPs) in language acquisition, it is essential to disentangle studies of late first language (L1) acquisition from those of second language (L2) acquisition. Their primary thesis is that timely exposure to an L1 is crucial for esta...
Article
Over the first weeks and months following birth, infants' initial, broad-based perceptual sensitivities become honed to the characteristics of their native language. In this article, we review this process of emerging specialization within the context of a cascading “critical period” (CP) framework, in which periods of maximal openness to experienc...
Chapter
This chapter discusses how the brain becomes specialized for supporting higher cognitive and language functions. We review behavioral milestones in several content areas, highlighting the interplay among them and their underlying neural foundations. We emphasize how the complex and lengthy process of brain development raises additional questions ab...
Article
At the end of the target article, Keven & Akins (K&A) put forward a challenge to the developmental psychology community to consider the development of complex psychological processes – in particular, intermodal infant perception – across different levels of analysis. We take up that challenge and consider the possibility that early emerging stereot...
Article
Full-text available
In this work we ask whether at birth, the human brain responds uniquely to speech, or if similar activation also occurs to a non-speech surrogate 'language'. We compare neural activation in newborn infants to the language heard in utero (English), to an unfamiliar language (Spanish), and to a whistled surrogate language (Silbo Gomero) that, while u...
Chapter
Language is a structured form of communication that is unique to humans. Within the first few years of life, typically developing children can understand and produce full sentences in their native language or languages. For centuries, philosophers, psychologists, and linguists have debated how we acquire language with such ease and speed. Central t...
Article
The period between six and 12 months is a sensitive period for language learning during which infants undergo auditory perceptual attunement, and recent results indicate that this sensitive period may exist across sensory modalities. We tested infants at three stages of perceptual attunement (six, nine, and 11 months) to determine (1) whether they...
Poster
Full-text available
The acoustic realization of phrasal prominence correlates systematically with the order of Verbs and Objects in natural languages. Prominence is realized as a durational contrast in V(erb)-O(bject) languages (English: short-long, to [Ro]me), and as a pitch/intensity contrast in O(bject)-V(erb) languages (Japanese: high-low, [‘To] kyo ni). Seven-mon...
Article
There is increasing interest in the link between early linguistic skills and later language development. In a longitudinal study, we investigated infants’ (a) ability to use speech sound categories to guide word learning in the habituation-based minimal pair switch task, and (b) early productive vocabulary, related to their concurrent and later lan...
Article
Full-text available
Visual information influences speech perception in both infants and adults. It is still unknown whether lexical representations are multisensory. To address this question, we exposed 18-month-old infants (n = 32) and adults (n = 32) to new word–object pairings: Participants either heard the acoustic form of the words or saw the talking face in sile...
Article
Mutual exclusivity is the assumption that each object has only one category label. Prior research suggests that bilingual infants, unlike monolingual infants, fail to adhere to this assumption to guide word learning. Yet previous work has not addressed whether bilingual infants systematically interpret a novel word for a familiar object (i.e. an ob...
Article
Sensory systems are thought to have evolved to efficiently represent the full range of sensory stimuli encountered in the natural world. The statistics of natural environmental sounds are characterized by scale-invariance: the property of exhibiting similar patterns at different levels of observation. The statistical structure of scale-invariant so...
Article
The influence of speech production on speech perception is well established in adults. However, because adults have a long history of both perceiving and producing speech, the extent to which the perception–production linkage is due to experience is unknown. We addressed this issue by asking whether articulatory configurations can influence infants...
Article
Some but not all neonates are affected by prenatal exposure to serotonin reuptake inhibitor antidepressants (SRI) and maternal mood disturbances. Distinguishing the impact of these two exposures is challenging and raises critical questions about whether pharmacological, genetic, or epigenetic factors can explain the spectrum of reported outcomes. U...
Article
Infants are able to match seen and heard speech even in non-native languages, and familiarization to audiovisual speech appears to affect subsequent auditory-only discrimination of non-native speech sounds (Danielson et al., 2013; 2014). However, the robustness of these behaviors appears to change rapidly within the first year of life. In this curr...
Article
Infants are sensitive to the correspondence between visual and auditory speech. Infants exhibit the McGurk effect, and matching audiovisual information may facilitate discrimination of similar consonant sounds in an infant’s native language (e.g., Teinonen et al., 2008). However, because most existing research in audiovisual speech perception has b...
Article
A continuing debate in language acquisition research is whether there are critical periods (CPs) in development during which the system is most responsive to environmental input. Recent advances in neurobiology provide a mechanistic explanation of CPs, with the balance between excitatory and inhibitory processes establishing the onset and molecular...
Article
Synaesthesia is a neurological condition in which input to one sense causes an automatic and consistent extra percept, often in another sense (e.g., C sharp elicits a pale yellow). Synaesthesia is hypothesized to arise, at least in part, from less-than-normal neural pruning of the exuberant connections in sensory cortical areas during infancy (revi...
Article
Full-text available
Increasing evidence suggests that the natural world has a special status for our sensory and cognitive functioning. The mammalian sensory system is hypothesized to have evolved to encode natural signals in an efficient manner. Exposure to natural stimuli, but not to artificial ones, improves learning and cognitive function. Scale-invariance, the pr...
Article
Forms that are nonlinguistic markers in one language (i.e., “tsk-tsk” in English) may be part of the phoneme inventory—and hence part of words—in another language. In the current paper, we demonstrate that infants' ability to learn words containing unfamiliar language sounds is influenced by the age and vocabulary size of the infant learner, as wel...
Article
Full-text available
A central component of language development is word learning. One characterization of this process is that language learners discover objects and then look for word forms to associate with these objects (Mcnamara, ; Smith, ). Another possibility is that word forms themselves are also important, such that once learned, hearing a familiar word form w...
Article
In this article, we begin with a summary of the evidence for perceptual narrowing for various aspects of language (e.g., vowel and consonant contrasts, tone languages, visual language, sign language) and of faces (e.g., own species, own race). We then consider possible reasons for the apparent differences in the timing of narrowing (e.g., apparentl...
Article
Full-text available
We have evaluated the use of phase synchronization to identify resting state functional connectivity (RSFC) in the language system in infants using functional near infrared spectroscopy (fNIRS). We used joint probability distribution of phase between fNIRS channels with a seed channel in the language area to estimate phase relations and to identify...
Data
We have evaluated the use of phase synchronization to identify resting state functional connectivity (RSFC) in the language system in infants using functional near infrared spectroscopy (fNIRS). We used joint probability distribution of phase between fNIRS channels with a seed channel in the language area to estimate phase relations and to identify...
Article
Full-text available
Absolute pitch, the ability to identify or produce the pitch of a sound without a reference point, has a critical period, i.e., it can only be acquired early in life. However, research has shown that histone-deacetylase inhibitors (HDAC inhibitors) enable adult mice to establish perceptual preferences that are otherwise impossible to acquire after...
Article
Full-text available
Adults as well as infants have the capacity to discriminate languages based on visual speech alone. Here, we investigated whether adults' ability to discriminate languages based on visual speech cues is influenced by the age of language acquisition. Adult participants who had all learned English (as a first or second language) but did not speak Fre...
Article
Significance Theories of language acquisition have typically assumed infants’ early perceptual capabilities influence the development of speech production. Here we show that the sensorimotor (production) system can also influence speech perception: Before infants are able to speak, their articulatory configurations affect the way they perceive spee...
Article
All languages employ certain phonetic contrasts when distinguishing words. Infant speech perception is rapidly attuned to these contrasts before many words are learned, thus phonetic attunement is thought to proceed independently of lexical and referential knowledge. Here, evidence to the contrary is provided. Ninety-eight 9-month-old English-learn...
Article
In ambiguous word learning situations, infants can use systematic strategies to determine the referent of a novel word. One such heuristic is disambiguation. By age 16-18months, monolinguals infer that a novel noun refers to a novel object rather than a familiar one (Halberda, 2003), while at the same age bilinguals and trilinguals do not reliably...
Article
Full-text available
Talking silently to ourselves occupies much of our mental lives, yet the mechanisms underlying this experience remain unclear. The following experiments provide behavioral evidence that the auditory content of inner speech is provided by corollary discharge. Corollary discharge is the motor system's prediction of the sensory consequences of its act...
Article
Full-text available
Speech is robustly audiovisual from early in infancy. Here we show that audiovisual speech perception in 4.5-month-old infants is influenced by sensorimotor information related to the lip movements they make while chewing or sucking. Experiment 1 consisted of a classic audiovisual matching procedure, in which two simultaneously displayed talking fa...
Article
This volume synthesizes and integrates the broad literature in the subdisciplines of developmental psychology. The volume features an opening chapter by the volume editor outlining the organization of the field, as well as a concluding chapter in which the volume editor outlines future directions for developmental psychology. This volume synthesize...
Conference Paper
Infant speech perception: Biological beginnings and experiential influences The foundations for language acquisition, arguably our most quintessential human achievement, are in place by birth. As will be reviewed in this talk, there is specialization in the human brain from birth for processing language and for learning its properties. Yet alread...
Article
Full-text available
A central problem in language acquisition is how children effortlessly acquire the grammar of their native language even though speech provides no direct information about underlying structure. This learning problem is even more challenging for dual language learners, yet bilingual infants master their mother tongues as efficiently as monolinguals...
Article
Full-text available
Children growing up bilingual face a unique linguistic environment. The current study investigated whether early bilingual experience influences the developmental trajectory of associative word learning, a foundational mechanism for lexical acquisition. Monolingual and bilingual infants (N = 98) were tested on their ability to learn dissimilar-soun...
Article
Language acquisition reflects a complex interplay between biology and early experience. Psychotropic medication exposure has been shown to alter neural plasticity and shift sensitive periods in perceptual development. Notably, serotonin reuptake inhibitors (SRIs) are antidepressant agents increasingly prescribed to manage antenatal mood disorders,...
Article
Phonological development involves learning the organisation of the individual sound units, the syllable structure, the rhythm, and the phonotactics of the native language, and utilising these in both productive and receptive language. The initial work in phonological development focused exclusively on production, with detailed description of the on...
Article
Full-text available
Critical periods in language acquisition have been discussed primarily with reference to studies of people who are deaf or bilingual. Here, we provide evidence on the opening of sensitivity to the linguistic environment by studying the response to a change of phoneme at a native and nonnative phonetic boundary in full-term and preterm human infants...
Article
One important mechanism suggested to underlie the acquisition of grammar is rule learning. Indeed, infants aged 0 ; 7 are able to learn rules based on simple identity relations (adjacent repetitions, ABB: "wo fe fe" and non-adjacent repetitions, ABA: "wo fe wo", respectively; Marcus et al., 1999). One unexplored issue is whether young infants are a...
Article
Full-text available
Infants begin life ready to learn any of the world’s languages, but they quickly become speech-perception experts in their native language. Although this phenomenon has been well described, the mechanisms leading to native-language-listening expertise have not. In this article, we provide an in-depth review of one learning mechanism: distributional...
Article
The origins of the bilingual advantage in various cognitive tasks are largely unknown. We tested the hypothesis that bilinguals' early capacities to track their native languages separately and learn about the properties of each may be at the origin of such differences. Spanish-Catalan bilingual and Spanish or Catalan monolingual infants watched sil...
Article
: The acoustic change complex (ACC), an auditory evoked potential (AEP) comprises overlapping slow cortical responses, which reflects discrimination capacity in the absence of attention, has not yet been recorded in infants. Because the ACC is a large response, it may be useful as an index of discrimination for infants at both the individual and gr...