Ann R Bradlow

• PhD, Cornell University, 1993
• Head of Faculty at Northwestern University

Researchers have generally assumed that listeners perceive speech compositionally, based on the combined processing of local acoustic–phonetic cues associated with individual linguistic units. Yet, these cue-based approaches have failed to fully account for variation in listeners’ identification of the words produced by a talker (i.e., variation in...

Bilingualism and the study of speech sounds are two of the largest areas of inquiry in linguistics. This Handbook sits at the intersection of these fields, providing a comprehensive overview of the most recent, cutting-edge work on the sound systems of adult and child bilinguals. Bringing together contributions from an international team of world-l...

Speech recognition by both humans and machines frequently fails in non-optimal yet common situations. For example, word recognition error rates for second-language (L2) speech can be high, especially under conditions involving background noise. At the same time, both human and machine speech recognition sometimes shows remarkable robustness against...

High-frequency speech information is susceptible to inaccurate perception in even mild to moderate forms of hearing loss. Some hearing aids employ frequency-lowering methods such as nonlinear frequency compression (NFC) to help hearing-impaired individuals access high-frequency speech information in more accessible lower-frequency regions. As such...

Hearing aid prescription protocols rely on estimates of speech spectra. One such estimate, the International Long-Term Average Speech Spectrum (ILTASS), is a common reference for the distribution of spectral energy within speech signals. However, recent research has suggested differences in speech spectra between some languages and the ILTASS stand...

Listeners can use lexical information to drive adaptation to talker-specific speech characteristics with a small amount of exposure. This suggests that adaptation may be strongest when listeners are initially exposed to speech in a condition that facilitates word recognition. This was tested by examining the intelligibility of second-language (L2)...

Measuring how well human listeners recognize speech under varying environmental conditions (speech intelligibility) is a challenge for theoretical, technological, and clinical approaches to speech communication. The current gold standard—human transcription—is time- and resource-intensive. Recent advances in automatic speech recognition (ASR) syste...

Recent work on perceptual learning for speech has suggested that while high-variability training typically results in generalization, low-variability exposure can sometimes be sufficient for cross-talker generalization. We tested predictions of a similarity-based account, according to which, generalization depends on training-test talker similarity...

Two independent lines of research have revealed a somewhat surprising convergence between clear speech and second-language (L2) speech. Specifically, relative to conversational L1 speech, both clear speech and L2 speech typically exhibit slower speaking rates (fewer syllables per second), longer and more frequent inter-word pauses, and less segment...

No PDF available ABSTRACT Northwestern University has a vibrant and interdisciplinary community of acousticians. Of the 13 ASA technical areas, 3 have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of departments inclu...

No PDF available ABSTRACT This talk will present the rationale and empirical foundation for an “asset-” rather than “deficit-based” framework for understanding bilingual speech communication. In this framework, first-language (L1) and second-language (L2) speech are viewed as distinct speech styles each of which is shaped by four interacting source...

No PDF available ABSTRACT Speech phonemes in higher frequencies have varying acoustic characteristics in different languages. For example, /s/ and /ʃ/, fricatives commonly used in English, have spectral peaks at higher frequencies than /ʂ/ and /x/, fricatives commonly used in Mandarin. Data on the relationship between the acoustic characteristics o...

Objectives: The role of subcortical synchrony in speech-in-noise (SIN) recognition and the frequency-following response (FFR) was examined in multiple listeners with auditory neuropathy. Although an absent FFR has been documented in one listener with idiopathic neuropathy who has severe difficulty recognizing SIN, several etiologies cause the neur...

Inspired by information theoretic analyses of L1 speech and language, this study proposes that L1 and L2 speech exhibit distinct information encoding and transmission profiles in the temporal domain. Both the number and average duration of acoustic syllables (i.e., intensity peaks in the temporal envelope) were automatically measured from L1 and L2...

Recordings of Spanish and English sentences by switched-dominance bilingual (SDB) Spanish (i.e., L2-dominant Spanish-English bilinguals) and by L1-dominant Spanish and English controls were presented to L1-dominant Spanish and English listeners, respectively. At –4 dB signal-to-noise ratio (SNR), Spanish and English productions by SDBs were equally...

Including contributions from a team of world-renowned international scholars, this volume is a state-of-the-art survey of second language speech research, showcasing new empirical studies alongside critical reviews of existing influential speech learning models. It presents a revised version of Flege's Speech Learning Model (SLM-r) for the first ti...

Both the timing (i.e., when) and amount (i.e., how much) of language exposure affect language-learning outcomes. We compared speech recognition accuracy across three listener groups for whom the order (first versus second) and dominance (dominant versus non-dominant) of two languages, English and Spanish, varied: one group of Spanish heritage speak...

No PDF available ABSTRACT Northwestern University has a vibrant and highly interdisciplinary community of acousticians. Of the 13 ASA technical areas, 3 have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of department...

No PDF available ABSTRACT Recognition of foreign-accented speech by older listeners with hearing loss has typically been examined with linguistically simple materials (words and short sentences), which may not capture the complexity of realistic speech experiences. In this study, older listeners with varying degrees of hearing acuity recognized sim...

Objective: The goal of this study was to assess recognition of foreign-accented speech of varying intelligibility and linguistic complexity in older adults. It is important to understand the factors that influence the recognition of this commonly encountered type of speech, in a population that remains understudied in this regard. Design: A repe...

Foreign-accented speech recognition is typically tested with linguistically simple materials, which offer a limited window into realistic speech processing. The present study examined the relationship between linguistic structure and talker intelligibility in several sentence-in-noise recognition experiments. Listeners transcribed simple/short and...

Memory for speech benefits from linguistic structure. Recall is better for sentences than for random strings of words (the “sentence superiority effect”; SSE), and evidence suggests that ongoing speech may be organized advantageously as clauses in memory (recall by word position shows within-clause U shape). In this study, we examined the SSE and c...

I will describe the “progressive co-authorship cycle” as a strategy for promoting student publishing success. Crucial points in this progression are: (1) an initial phase in which the advisor is the lead author on a co-authored publication, (2) a middle phase in which the student and advisor are both in transition, and (3) a final phase in which th...

The present study provides evidence of a positive correlation between L1 and L2 intelligibility for bilingual talkers. Each talker in a group of Mandarin-English and Korean-English bilinguals was recorded producing simple sentences in each of their languages. The recordings were then presented to native listeners of the language-being-spoken in a t...

The bulk of the work on non-native speech has focused on average differences between L1 and L2 speakers. However there is growing evidence that variability also plays an important role in distinguishing L1 from L2 speech. While some studies have demonstrated greater variability for non-native than native speech (e.g., Baese-Berk & Morrill, 2015; Wa...

How does linguistic knowledge influence speech production, perception, and learning? In this presentation, I will review three sources of empirical evidence for language specificity in some of the most basic processes of speech communication. Each line of evidence will highlight the contributions of the remarkable Jongman-Sereno collaboration—the h...

In adverse communicative contexts, speakers will modify their speech style to enhance intelligibility, which can involve a range of acoustic and articulatory adjustments. Prior work has focused on the influence of speaking style on spectral (e.g., vowel space expansion) and temporal distinctions (e.g., voice-onset time). Thus, this study investigat...

The current study investigated the phonetic adjustment mechanisms that underlie perceptual adaptation in first and second language (Dutch-English) listeners by exposing them to a novel English accent containing controlled deviations from the standard accent (e.g. /i/-to-/ɪ/ yielding /krɪm/ instead of /krim/ for 'cream'). These deviations involved c...

Foreign-accented speech recognition is typically tested with linguistically simple sentences, which offer a limited window into speech processing. In this study, participants transcribed simple (i.e. mono-clausal, canonical declarative syntax) and complex (i.e. multi-clausal, non-canonical syntax, and/or passive voice) sentences in noise at two sig...

Comprehension of foreign-accented speech improves with exposure. Previous work demonstrates that listeners who adapt to accented talkers generalize that adaptation to other accented talkers—exposure to multiple talkers of the same accent facilitates comprehension of a novel talker of that accent (e.g. Bradlow and Bent, 2008) and exposure to multipl...

Prior research has demonstrated that listeners are sensitive to changes in the indexical (talker-specific) characteristics of speech input, suggesting that these signal-intrinsic features are integrally encoded in memory for spoken words. Given that listeners frequently must contend with concurrent environmental noise, to what extent do they also e...

Northwestern University has a vibrant and highly interdisciplinary community of acousticians. Of the 13 ASA technical areas, 3 have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of departments including Linguistics (i...

Second-language (L2) speech is consistently slower than first-language (L1) speech, and L1 speaking rate varies within- and across-talkers depending on many individual, situational, linguistic, and sociolinguistic factors. It is asked whether speaking rate is also determined by a language-independent talker-specific trait such that, across a group...

In this study, we consider how native status and signal degradation influence French listeners’ segmentation of an incoming speech stream containing 'liaison', a phonological process that misaligns word and syllable boundaries. In particular, we investigate how both first language (L1) and second language (L2) French listeners compensate for the sy...

Adaptation to foreign-accented sentences can be guided by knowledge of the lexical content of those sentences, which, being an exact match for the target, provides feedback on all linguistic levels. The extent to which this feedback needs to match the accented sentence was examined by manipulating the degree of match on different linguistic dimensi...

While indexical information is implicated in many levels of language processing, little is known about the internal structure of the system of indexical dimensions, particularly in bilinguals. A series of three experiments using the speeded classification paradigm investigated the relationship between various indexical and non-linguistic dimensions...

This study examined the temporal dynamics of spoken word recognition in noise and background speech. In two visual-world experiments, English participants listened to target words while looking at four pictures on the screen: a target (e.g. candle), an onset competitor (e.g. candy), a rhyme competitor (e.g. sandal), and an unrelated distractor (e.g...

Bilinguals are known to perform worse than monolinguals on speech-in-noise tests. However, the mechanisms underlying this difference are unclear. By varying the amount of linguistic information available in the target stimulus across five auditory-perception-in-noise tasks, we tested if differences in language-independent (sensory/cognitive) or lan...

When talkers are aware of listeners’ speech perception difficulties due to hearing loss, noise, or a language barrier, they typically adopt an intelligibility-enhancing speaking style known as “clear speech.” To the extent that clear speech is more intelligible than “conversational speech,” a cross-style acoustic-phonetic comparison provides inform...

Native and non-native speech differ in many ways, including overall speech rate, which tends to be substantially slower for non-native speakers (Guion et al., 2000). Recent work has suggested that non-native speech may be not only slower, but also more variable when non-natives are reading aloud (Baese-Berk and Morrill, 2015). Speaking rate also in...

Coda neutralization in Korean induces a wide range of homophony. It thus makes Korean an ideal language of research for whether neutralization is phonetically complete or not. However, only one relatively small-scale study documented that manner neutralization of codas (one of 3 types of coda neutralization in Korean) is phonetically complete in pr...

Language acquisition typically involves periods when the learner speaks and listens to the new language, and others when the learner is exposed to the language without consciously speaking or listening to it. Adaptation to variants of a native language occurs under similar conditions. Here, speech learning by adults was assessed following a trainin...

Learning to read is a fundamental developmental milestone, and achieving reading competency has lifelong consequences. Although literacy development proceeds smoothly for many children, a subset struggle with this learning process, creating a need to identify reliable biomarkers of a child's future literacy that could facilitate early diagnosis and...

The phonetic manifestation of phonological contrast neutralization is of long-standing interest for our understanding of the phonetic realization of phonological structure. Korean phonology is particularly interesting in this regard with three dimensions of coda contrast neutralization: laryngeal, manner, and palatal. Extending previous work (Kim &...

Speech processing can often take place in adverse listening conditions that involve the mixing of speech and background noise. In this study, we investigated processing dependencies between background noise and indexical speech features, using a speeded classification paradigm (Garner, 1974; Exp. 1), and whether background noise is encoded and repr...

When a firm conducts business across borders to exploit location, scale or scope economies, it inevitably encounters nontrivial costs of language communication that can dissipate the value that it attempts to create through its international activities. As such, mitigating the detrimental influences of language distance has important performance im...

Northwestern University has a vibrant and highly interdisciplinary community of acousticians. Of the 13 ASA technical areas, three have strong representation at Northwestern: Speech Communication, Psychological and Physiological Acoustics, and Musical Acoustics. Sound-related work is conducted across a wide range of departments including Linguistic...

Speech recognition is highly sensitive to adverse conditions at all stages of the speech chain, i.e., the sequence of events that transmits a message from the mind/brain of a speaker through the acoustic medium to the mind/brain of a listener. Adverse conditions can originate from source degradations (e.g., disordered or foreign-accented speech), e...

Switched dominance bilinguals (i.e., “heritage speakers,” HS, with L2 rather than L1 dominance) have exhibited native-like heritage language (L1) sound perception (e.g., Korean three-way VOT contrast discrimination by Korean HS; Oh, Jun, Knightly, & Au, 2003) and sound production (e.g., Spanish VOT productions by Spanish HS; Au, Knightly, Jun, & Oh...

This study examined the influence of background language variation on speech recognition. English listeners performed an English sentence recognition task in either "pure" background conditions in which all trials had either English or Dutch background babble or in mixed background conditions in which the background language varied across trials (i...

This study examined whether language specific properties may lead to cross-language differences in the degree of phonetic reduction. Rates of syllabic reduction (defined here as reduction in which the number of syllables pronounced is less than expected based on canonical form) in English and Mandarin were compared. The rate of syllabic reduction w...

Background: Masking release for an English sentence-recognition task in the presence of foreign-accented English speech compared with native-accented English speech was reported in Calandruccio et al (2010a). The masking release appeared to increase as the masker intelligibility decreased. However, it could not be ruled out that spectral differenc...

Speech processing can often take place in listening conditions that involve the mixing of speech and background noise. This study used a speeded classification paradigm to investigate whether background noise is perceptually integrated with indexical (Exp. 1) and phonetic (Exp. 2) dimensions of the speech signal. In each experiment, English listene...

When a firm conducts business across borders to exploit location, scale or scope economies, it inevitably encounters nontrivial costs of language communication that can dissipate the value that it attempts to create through its international activities. As such, mitigating the detrimental influences of language distance has important performance im...

Talker familiarity can facilitate the extraction of linguistic content from speech signals embedded in broadband noise; however, relatively little research has investigated the impact of talker familiarity with competing speech in the background. This study explores the effects of familiarity with the target or competing talker in speech-in-speech...

Previous research suggests that accuracy (i.e., distance to the average location of native productions) has less effect on adaption to non-native speech than category variability [e.g., Wade et al., Phonetica 64, 122-144 (2007)]. Here we investigate the relationship between overall intelligibility of Mandarin-accented English for native English lis...

Nonnative talkers tend to exhibit slower speech rates than native talkers at the group level. Here we ask whether individual variation in rate is language-general to the extent that L1 rate is a significant predictor of L2 rate within bilinguals. 62 nonnative English talkers participated in three speech production tasks in both their L1 (14 Cantone...

Purpose To investigate masking release for speech maskers for linguistically and phonetically close (English and Dutch) and distant (English and Mandarin) language pairs. Method Thirty-two monolingual speakers of English with normal audiometric thresholds participated in the study. Data are reported for an English sentence recognition task in Engl...

While the relationship of speaking style to intelligibility under challenging conditions has been established, it is a common observation that some speakers seem to be more intelligible than others for most listeners. In previous work, we have reported that automatic measures based on the technique of Landmark Detection appear to track differences...

Many English conversations across the globe today involve talkers with different language experiences. Here we show that, while language barriers challenge communicative efficiency, the detrimental effect of language distance may be mitigated by phonetic convergence. We analyzed a corpus of 42 conversations in which talker pairs solved a spot-the-d...

Nonnative talkers tend to exhibit slower speech rates than native talkers at the group level. Here we ask whether individual variation in rate is language-general to the extent that L1 rate is a significant predictor of L2 rate within bilinguals. 62 nonnative English talkers participated in three speech production tasks in both their L1 (14 Cantone...

Foreign-accented speech can be difficult to understand but listeners can adapt to novel talkers and accents with appropriate experience. Previous studies have demonstrated talker-independent but accent-dependent learning after training on multiple talkers from a single language background. Here, listeners instead were exposed to talkers from five l...

In most of the world, people have regular exposure to multiple accents. Therefore, learning to quickly process accented speech is a prerequisite to successful communication. In this paper, we examine work on the perception of accented speech across the lifespan, from early infancy to late adulthood. Unfamiliar accents initially impair linguistic pr...

Children with dyslexia often exhibit increased variability in sensory and cognitive aspects of hearing relative to typically developing peers. Assistive listening devices (classroom FM systems) may reduce auditory processing variability by enhancing acoustic clarity and attention. We assessed the impact of classroom FM system use for 1 year on audi...

This study asks whether speech recognition by bilingual listeners in each of their two languages follow complementary or supplementary patterns. Previous studies showed that early bilinguals are disproportionately affected by adverse listening conditions in L2 (Mayo et al., 1997; Shi et al, 2010; Bradlow & Alexander, 2007), but did not measure perf...

We investigated native English talkers' phonetic accommodation to a native or nonnative model talker in a passive auditory exposure setting. We performed a phonetic accommodation experiment, following the procedure of Goldinger & Azuma (2004). Specifically, the imitators read monosyllabic words, disyllabic words, and sentences before and after perc...

Previous research has shown that L1 speech intelligibility, as judged by native listeners, varies due to speaker-specific characteristics. Similarly, L2 speech intelligibility as judged by native listeners also varies across speakers. Given variability in L1 and L2 intelligibility, we hypothesize that, within bilinguals, some speaker-specific chara...

This study investigated variability in L2 speech intelligibility as a function of L1 speech intelligibility and of talker-listener L1 match. Non-native Korean talkers varying in their L2 proficiency were recorded reading simple English (L2) and Korean (L1) sentences. The intelligibility of these sentences was then assessed by Korean listeners (both...

This article presents a review of the effects of adverse conditions (ACs) on the perceptual, linguistic, cognitive, and neurophysiological mechanisms underlying speech recognition. The review starts with a classification of ACs based on their origin: Degradation at the source (production of a noncanonical signal), degradation during signal transmis...

This paper explores how theories on the relationship between language and domain-general cognitive capabilities might account for individual variation in second language learning. We investigated the acquisition of a morphophonological grammar paired with standardized tests of memory function. The language learned had simple and complex morphophono...

The concept of subliminal perception has been a subject of interest and controversy for decades. Of interest in the present investigation was whether a neurophysiologic index of stimulus change could be elicited to speech sound contrasts that were consciously indiscriminable. The stimuli were chosen on the basis of each individual subject’s discrim...

This study examined whether speech-on-speech masking is sensitive to variation in the degree of similarity between the target and the masker speech. Three experiments investigated whether speech-in-speech recognition varies across different background speech languages (English vs Dutch) for both English and Dutch targets, as well as across variatio...

This study investigated how native language background interacts with speaking style adaptations in determining levels of speech intelligibility. The aim was to explore whether native and high proficiency non-native listeners benefit similarly from native and non-native clear speech adjustments. The sentence-in-noise perception results revealed tha...

This special issue of the Journal contains a selection of papers developed from original presentations at the 2nd ASA Special Workshop on Speech with the theme of Cross-Language Speech Perception and Variations in Linguistics Experience. The papers represent major theoretical and empirical contributions that converge upon the common theme of how ou...

Clear speech is an intelligibility-enhancing mode of communication often used when speakers have trouble being understood. Previous work has established that both native and non-native listeners can receive a clear speech perception benefit, though possibly to differing degrees (Bradlow and Bent, 2002). Few studies have looked at whether nonnative...

This study explores phonetic convergence during conversations between pairs of talkers with varying language distance. Specifically, we examined conversations within two native English talkers and within two native Korean talkers who had either the same or different regional dialects, and between native and nonnative talkers of English. To measure...

In this study, we compare the effects of English lexical features on word duration for native and non-native English speakers and for non-native speakers with different L1s and a range of L2 experience. We also examine whether non-native word durations lead to judgments of a stronger foreign accent. We measured word durations in English paragraphs...

We motivate and present a corpus of scripted and spontaneous speech in both the native and the non-native language of talkers from various language backgrounds. Using corpus recordings from 11 native English and 11 late Mandarin-English bilinguals we compared speech timing across native English, native Mandarin, and Mandarin-accented English. Findi...

Listeners' interactions often take place in auditorily challenging conditions. We examined how noise affects phonological competition during spoken word recognition. In a visual-world experiment, which allows us to examine the time-course of recognition, English participants listened to target words in quiet and in noise while they saw four picture...

In this paper, we consider what can be gained by aggregating smaller, individual recording collections into large, user-centric web-based archives. We review two web-based archiving projects, the Online Speech/Corpora Archive and Analysis Resource (OSCAAR) and the Sociolinguistic Archive and Analysis Project (SLAAP), both of which feature organizat...

This paper describes the development of the Wildcat Corpus of native- and foreign-accented English,a corpus containing scripted and spontaneous speech recordings from 24 native speakers of American English and 52 non-native speakers of English.The core element of this corpus is a set of spontaneous speech recordings, for which a new method of elici...

Purpose It is established that speaking clearly is an effective means of enhancing intelligibility. Because any signal-processing scheme modeled after known acoustic–phonetic features of clear speech will likely affect both target and competing speech, it is important to understand how speech recognition is affected when a competing speech signal i...

The goal of the present study was to devise a means of representing languages in a perceptual similarity space based on their overall phonetic similarity. In Experiment 1, native English listeners performed a free classification task in which they grouped 17 diverse languages based on their perceived phonetic similarity. A similarity matrix of the...

Previous research has shown that monolingual English listeners receive a release from informational masking if the competing speech is foreign-language versus native-language noise [e.g., Van Engen & Bradlow (2007)]. This study examines whether speech-in-speech recognition varies even across typologically close target and noise languages (English v...

It has been reported that listeners can benefit from a release in masking when the masker speech is spoken in a language that differs from the target speech compared to when the target and masker speech are spoken in the same language [Freyman, R. L. et al. (1999). J. Acoust. Soc. Am. 106, 3578-3588; Van Engen, K., and Bradlow, A. (2007), J. Acoust...

This guide accompanies the following article : Rajka Smiljanic and Ann Bradlow, ‘Speaking and Hearing Clearly: Talker and Listener Factors in Speaking Style Changes’, Langauge and Linguistics Compass 3/1 (2009): DOI: 10.1111/j.1749‐818X.2008.00112.x Author’s Introduction Clear speech is a listener‐oriented speech modification that talkers naturall...

This article examines how probability (lexical frequency and previous mention), speech style, and prosody affect word duration, and how these factors interact. Participants read controlled materials in clear and plain speech styles. As expected, more probable words (higher frequencies and clear speech second mentions) were significantly shorter tha...

Foreign‐accented speech presents an interesting challenge for native listeners due to its deviations from native accented speech along multiple acoustic‐phonetic dimensions. Nevertheless, since these deviations arise primarily from interactions of the native (L1) and target (L2) language sound systems, they are highly systematic both within individ...

Most second language acquisition research focuses on linguistic structures, and less research has examined the acquisition of sociolinguistic patterns. The current study explored the perceptual classification of regional dialects of American English by native and non-native listeners using a free classification task. Results revealed similar classi...