Alexander L Francis

Alexander L Francis
Purdue University | Purdue · Department of Speech, Language and Hearing Sciences

Ph.D.

About

111
Publications
17,189
Reads
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3,116
Citations
Citations since 2017
24 Research Items
1533 Citations
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Introduction
I am interested in the relationship between attention, effort, and stress when speech perception becomes difficult. We use behavioral and psychophysiological techniques to assess these factors in younger and older adults with and without hearing impairment when listening to speech in various types of background noise or when distorted or produced with an unfamiliar foreign accent.
Additional affiliations
January 2008 - present
Purdue University
Position
  • Effects of cognitive and auditory aging on speech perception
August 2002 - present
Purdue University
Position
  • Effects of auditory and linguistic experience on speech perception
August 1999 - August 2002
The University of Hong Kong
Position
  • Perception, production and perceptual learning of lexical tones
Description
  • Still an interest of mine, and something I work on when I have the opportunity!
Education
August 1999 - August 2002
The University of Hong Kong
Field of study
  • Speech and Hearing Sciences
October 1991 - August 1999
University of Chicago
Field of study
  • Linguistics and Cognitive Psychology

Publications

Publications (111)
Article
No PDF available ABSTRACT We have previously shown that individual personality traits, including noise sensitivity, can influence listeners’ assessment of effort and frustration related to noise that interferes with a listening task. Here, we extend our previous research to employ stimuli from a commonly used speech-in-noise task, the coordinate re...
Article
Full-text available
Exposure to noise—or unwanted sound—is considered a major public health issue in the United States and internationally. Previous work has shown that even acute noise exposure can influence physiological response in humans and that individuals differ markedly in their susceptibility to noise. Recent research also suggests that specific acoustic prop...
Article
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Background Differences in non-social attentional functions have been identified as among the earliest features that distinguish infants later diagnosed with autism spectrum disorder (ASD), and may contribute to the emergence of core ASD symptoms. Specifically, slowed attentional disengagement and difficulty reorienting attention have been found acr...
Article
Background: Hearing loss is associated with a greater risk of death in older adults. This relationship has been attributed to an increased risk of injury, particularly due to falling, in individuals with hearing loss. However, the link between hearing loss and mortality across the lifespan is less clear. Methods: We used structural equation mode...
Chapter
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...
Article
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Listeners vary in their ability to understand speech in adverse conditions. Differences in both cognitive and linguistic capacities play a role, but increasing evidence suggests that such factors may contribute differentially depending on the listening challenge. Here, we used multilevel modeling to evaluate contributions of individual differences...
Conference Paper
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This paper presents a proof-of-concept for contactless and nonintrusive estimation of electrodermal activity (EDA) correlates using a camera. RGB video of the palm under three different lighting conditions showed that for a suitably chosen illumination strategy the data from the camera is sufficient to estimate EDA correlates which agree with the m...
Article
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Dysregulation of the autonomic nervous system (ANS), which can be indexed by heart rate variability (HRV), has been posited to contribute to core features of autism spectrum disorder (ASD). However, the relationship between ASD and HRV remains uncertain. We assessed tonic and phasic HRV of 21 children with ASD and 21 age- and IQ-matched typically d...
Article
Bilinguals’ attitudes toward their languages can be a major source of linguistic variability. However, the effect of attitudes on crosslinguistic phonetic interactions in bilinguals remains largely unexplored. This study investigated the possibility of such effects in Cantonese-English bilinguals in Hong Kong ( n = 26). Participants produced near-h...
Article
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Despite early differences in orienting to sounds, no study to date has investigated whether children with ASD demonstrate impairments in attentional disengagement in the auditory modality. Twenty-one 9–15-year-old children with ASD and 20 age- and IQ-matched TD children were presented with an auditory gap–overlap paradigm. Evidence of impaired dise...
Article
No PDF available ABSTRACT Listening to speech in background noise is cognitively demanding and has been shown to engage frontal cortical regions associated with selective attention and cognitive control. However, especially for noise-sensitive individuals, the presence of interfering or distracting noise may also provoke anxiety or frustration, and...
Article
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Listening effort is increasingly recognized as a factor in communication, particularly for and with nonnative speakers, for the elderly, for individuals with hearing impairment and/or for those working in noise. However, as highlighted by McGarrigle et al., International Journal of Audiology, 2014, 53, 433-445, the term "listening effort" encompass...
Article
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Objective The purpose of this study was to explore the hypothesis that the relationship between hearing problems and cardiovascular disease (CVD) includes a connection to psychological distress. Design We used generalized structural equation modeling to assess relationships between self-reported measures of hearing problems, psychological distress...
Article
Workplace noise may cause stress that has long-term implications for health. Employees in open-plan offices typically identify intermittently occurring background sounds as significant sources of stress, possibly because they distract attention away from intended tasks. Thus, individual differences in attention and noise sensitivity may explain ind...
Article
Unexpected sounds are distracting and can be annoying but individuals may differ in susceptibility to them. Irrelevant sounds occurring at sparse temporal intervals induce a psychophysiological orienting response reflecting involuntary capture of attention away from the primary task. We hypothesize that the frequency and/or magnitude of individual...
Article
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When people make decisions about listening, such as whether to continue attending to a particular conversation or whether to wear their hearing aids to a particular restaurant, they do so on the basis of more than just their estimated performance. Recent research has highlighted the vital role of more subjective qualities such as effort, motivation...
Article
Purpose The purpose of this study was to investigate the effects of 2nd language proficiency and linguistic uncertainty on performance and listening effort in mixed language contexts. Method Thirteen native speakers of Dutch with varying degrees of fluency in English listened to and repeated sentences produced in both Dutch and English and present...
Article
People who work in noisy environments are at greater risk for stress-related diseases, including hypertension and stroke, even when noise levels are too low to damage hearing. Such noise may be harmful, especially to noise-sensitive individuals, because the psychological annoyance that it causes induces physiological stress responses that are damag...
Conference Paper
Unexpected sounds are distracting and can be annoying but individuals may differ in susceptibility to them. Irrelevant sounds occurring at sparse temporal intervals induce a psychophysiological orienting response reflecting involuntary capture of attention. We hypothesize that the frequency and/or magnitude of individual listeners’ orienting respon...
Article
Full-text available
In recent years, there has been increasing interest in studying listening effort. Research on listening effort intersects with the development of active theories of speech perception and contributes to the broader endeavor of understanding speech perception within the context of neuroscientific theories of perception, attention, and effort. Due to...
Article
Physiological responses linked to listening effort may differ depending on whether the increased effort is due to masking vs. distortion of the speech signal (Francis, et al. 2016; Zekveld, et al. 2014), suggesting that listeners may engage different cognitive strategies to compensate for different sources of reduced intelligibility. Here, we asses...
Article
Two-tone suppression reduces gain in the cochlea nearly instantaneously in a frequency-dependent manner. In speech perception, suppression may enhance spectral contrasts between regions of higher and lower energy. A few previous studies have investigated the effects of aging on suppression and correlations with speech perception in noise, but none...
Article
Listening to speech in noise can be effortful, and the presence of background noise may in itself provoke physiologically measurable stress. Typical laboratory tests of speech perception in noise often present masked stimuli in trials separated by silence, in effect starting and stopping an otherwise constant background noise multiple times over th...
Article
Native speakers of Spanish with different amounts of experience with English classified stop-consonant voicing (/b/ versus /p/) across different speech accents: English-accented Spanish, native Spanish, and native English. While listeners with little experience with English classified target voicing with an English- or Spanish-like voice onset time...
Article
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Typically, understanding speech seems effortless and automatic. However, a variety of factors may, independently or interactively, make listening more effortful. Physiological measures may help to distinguish between the application of different cognitive mechanisms whose operation is perceived as effortful. In the present study, physiological and...
Article
Bilingual speakers’ speech varies phonetically according to many factors such as age of arrival and of acquisition of the second language (L2) (e.g., Flege et al., 1999). However, such temporal factors may not be as relevant to populations with more uniform language experience, as in pervasively multilingual societies. In such diglossic situations,...
Article
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The notion of listening effort has enjoyed a resurgence in recent years, with new work appearing in both theoretically and clinically oriented venues, and researchers pursuing this topic with an increasingly inventive suite of methods. Listening effort is often associated with perceptual and/or cognitive processing demands for understanding speech,...
Article
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The covariation of onset f0 with voice onset time (VOT) was examined across and within phonological voicing categories in two languages, English and Spanish. The results showed a significant co-dependency between onset f0 and VOT across phonological voicing categories but not within categories, in both languages. Thus, English short lag and long la...
Article
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Both long-term native language experience and immediate linguistic expectations can affect listeners' use of acoustic information when making a phonetic decision. In this study, a Garner selective attention task was used to investigate differences in attention to consonants and tones by American English-speaking listeners (N = 20) and Mandarin Chin...
Article
Researchers tend to quantify degree of bilingualism according to age-related factors such as age of acquisition (Flege, et al. 1999, Yeni-Komshian, et al. 2000). However, previous research suggests that bilinguals may also show different degrees of accent and patterns of phonetic interaction between their first language (L1) and second language (L2...
Article
Non-native accented speech is typically less intelligible and less fluent than native speech, but it is unclear how these factors interact to influence perceived speech quality. To investigate this question, the speech of 20 non-native speakers of English varying in proficiency and native language was evaluated. Subjective measures of speech qualit...
Article
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The role of secondary cues in voicing categorization was investigated in three listener groups: Monolingual English (n = 20) and Spanish speakers (n = 20), and Spanish speakers with significant English experience (n = 16). Results showed that, in all three groups, participants used onset f0 in making voicing decisions only in the positive voice ons...
Article
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This study addresses whether there is a threshold, some particular length of silent gap between two speakers' turns, at which negative social attributions emerge. The effect of such inter-turn silence was tested by constructing dialogues where responses to requests were identical and affirmative so that study participants' (n = 380) ratings about "...
Article
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This study examines English speakers' relative weighting of two voicing cues in production and perception. Participants repeated words differing in initial consonant voicing ([b] or [p]) and labeled synthesized tokens ranging between [ba] and [pa] orthogonally according to voice onset time (VOT) and onset f0. Discriminant function analysis and logi...
Article
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Learning new phonetic categories in a second language may be thought of in terms of learning to focus one’s attention on those parts of the acoustic-phonetic structure of speech that are phonologically relevant in any given context. As yet, however, no study has demonstrated directly that training can shift listeners’ attention between acoustic cue...
Article
Previous research has shown that the perceptual categorization of a target lexical tone depends on its surrounding tonal context ("tone normalization"). Native speakers have been shown to take into account both preceding and following tonal context in order to carry out the normalization process. The present study focused on the effects of the dura...
Article
A current theoretical view proposes that infants converge on the speech categories of their native language by attending to frequency distributions that occur in the acoustic input. To date, the only empirical support for this statistical learning hypothesis comes from studies where a single, salient dimension was manipulated. Additional evidence i...
Article
Increasing the spatial separation of target and masking speech improves speech recognition but this benefit tends to decline with age. Previous research suggests that perceived spatial separation of targets and maskers facilitates selective attention, a mechanism that depends in part on the availability of working memory capacity. Thus, age?related...
Chapter
Full-text available
Features serve two main purposes in the phonology of languages: First, they delimit sets of sounds that participate in phonological processes and patterns (the classificatory function); and, second, they encode the distinction between pairs of contrastive phonemes (the distinctive function). In this chapter, we summarize evidence from a variety of...
Article
This study investigates the role of two processes, cue enhancement (learning to attend to acoustic cues which characterize a speech contrast for native listeners) and cue inhibition (learning to ignore cues that do not), in the acquisition of the American English tense and lax ([i] vs.[I]) vowels by native Spanish listeners. This contrast is acoust...
Article
Although vowel quality is an important cue to the perception of English lexical stress, few studies have examined the role this cue plays for non-native speakers. Previous research found that Mandarin speakers had problems using vowel reduction as a cue in English lexical stress production. Assuming native-like perception is a prerequisite to nativ...
Article
Full-text available
Perception of speech in competing speech is facilitated by spatial separation of the target and distracting speech, but this benefit may arise at either a perceptual or a cognitive level of processing. Load theory predicts different effects of perceptual and cognitive (working memory) load on selective attention in flanker task contexts, suggesting...
Article
Research on the acquisition of non‐native speech sounds is frequently conducted within the framework of theories that were originally developed to account for aspects of cross‐language speech perception (e.g., PAM, NLM, and the SLM). Such theories typically focus on the influence of native phonetic categories on the perception of non‐native speech,...
Article
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Understanding low-intelligibility speech is effortful. In three experiments, we examined the effects of intelligibility on working memory (WM) demands imposed by perception of synthetic speech. In all three experiments, a primary speeded word recognition task was paired with a secondary WM-load task designed to vary the availability of WM capacity...
Article
This paper reviews some current research exploring the role that capacity limitations play in recognizing speech, particularly in the presence of competing speech. Load theory [Lavie, Trends Cogn Sci 92 (2005)] suggests that perceptual capacity limits the number of objects (or features) that can be processed simultaneously, while cognitive capacity...
Article
This study investigates the role of two processes, cue enhancement (learning to attend to acoustic cues which characterize a speech contrast for native listeners) and cue inhibition (learning to ignore cues that do not), in the acquisition of the American English tense and lax ([i] and [I]) vowels by native Spanish listeners. This contrast is acous...
Article
Full-text available
Information-processing limitations have been associated with language problems in children with specific language impairment (SLI). These processing limitations may be associated with limitations in attentional capacity, even in the absence of clinically significant attention deficits. In this study, the authors examined the performance of 4- to 6-...
Article
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Two studies explored the role of native language use of an acoustic cue, vowel duration, in both native and non-native contexts in order to test the hypothesis that non-native listeners' reliance on vowel duration instead of vowel quality to distinguish the English tense/lax vowel contrast could be explained by the role of duration as a cue in nati...
Article
Previous work suggests that learning to perceive speech categories in infancy may be influenced by the distributions of acoustic cues that underlie them. However, studies on this topic have focused on distributions of single cues, especially voice onset time (VOT), whereas natural phonetic categories are typically defined according to multiple cues...
Article
Acoustically, English lexical stress is multidimensional, involving F0, duration, intensity, and vowel quality. Previous research found that Mandarin speakers had problems using vowel reduction in English lexical stress production. Assuming nativelike perception is a prerequisite to nativelike production for non-native speech, the weight of vowel q...
Article
Full-text available
In English, voiced and voiceless syllable-initial stop consonants differ in both fundamental frequency at the onset of voicing (onset F0) and voice onset time (VOT). Although both correlates, alone, can cue the voicing contrast, listeners weight VOT more heavily when both are available. Such differential weighting may arise from differences in the...
Article
Full-text available
The aim of this study was to examine processing interactions between segmental (consonant, vowel) and suprasegmental (tone) dimensions of Mandarin Chinese. Using a speeded classification paradigm, processing interactions were examined between each pair of dimensions. Listeners were asked to attend to one dimension while ignoring the variation along...
Article
Full-text available
Native speakers of Mandarin Chinese have difficulty producing native-like English stress contrasts. Acoustically, English lexical stress is multidimensional, involving manipulation of fundamental frequency (F0), duration, intensity and vowel quality. Errors in any or all of these correlates could interfere with perception of the stress contrast, bu...
Article
Two groups of listeners, one of native speakers of a tone language (Mandarin Chinese) and one of native speakers of a non-tone language (English) were trained to recognize Cantonese lexical tones. Performance before and after training was measured using closed response-set identification and pairwise difference rating tasks. Difference ratings were...
Article
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Investigate training-related changes in acoustic-phonetic representation of consonants produced by a text-to-speech (TTS) computer speech synthesizer. Forty-eight adult listeners were trained to better recognize words produced by a TTS system. Nine additional untrained participants served as controls. Before and after training, participants were te...
Article
Listeners? ability to attend to a specific talker while ignoring simultaneous speech from another talker (the ??cocktail party?? problem) is not yet well understood. Lavie?s load theory [Trends Cogn. Sci. 9(2), 2005], originally developed in the visual modality, conceptualizes selective attention as a limited?capacity resource and provides a method...
Article
The word attention is beginning to appear more frequently in speech research, but closer examination suggests that this term can refer to a variety of potentially unrelated phenomena. The goal of this talk is to begin a discussion of these various phenomena, in the form of a preliminary, and subjective, overview of some areas of speech perception r...
Article
Full-text available
One production and one perception experiment were conducted to investigate the interaction of consonant voicing and fundamental frequency at the onset of voicing (onset f0) in Cantonese, a tonal language. Consonantal voicing in English can affect onset f0 up to 100 ms after voicing onset, but existing research provides inconclusive information rega...
Article
We examined the influence of listeners native phonology on the perception of American English tense and lax front unrounded vowels ([i] and [■]). These vowels are distinguishable according to both spectral quality and duration. Nineteen Russian, 18 Spanish, and 16 American English listeners identified stimuli from a beat‐bit continuum varying in ni...
Article
The learning of non‐native (Cantonese) tonal categories by native speakers of another tonal language (Mandarin) was investigated under two learning conditions. For listeners in the tonal context (TC) group, learning occurred by listening to target tones within various carrier phrases. Listeners in the no‐context group (NC) were trained using target...
Article
Native speakers of Mandarin Chinese have difficulty producing nativelike English stress contrasts. Acoustically, English lexical stress is multidimensional, involving manipulation of fundamental frequency (f0), duration, amplitude, and vowel quality. Errors in any or all of these correlates could result in poor realization of the stress contrast, b...
Article
Phonetic experience can change the perceptual distance between speech sounds, increasing both within‐category similarity and between‐category distinctiveness. Such warping of perceptual space is frequently characterized in terms of changes in selective attention: Listeners are assumed to attend more strongly to category‐differentiating features whi...
Article
This study combined behavioral and electrophysiological measurements to investigate interactions during speech perception between native phonemes and talker's voice. In a Garner selective attention task, participants either classified each sound as one of two native vowels ([epsilon] and [ae]), ignoring the talker, or as one of two male talkers, ig...
Article
We examined the effect of perceptual training on a well-established hemispheric asymmetry in speech processing. Eighteen listeners were trained to use a within-category difference in voice onset time (VOT) to cue talker identity. Successful learners (n=8) showed faster response times for stimuli presented only to the left ear than for those present...
Article
The forms, functions, and organization of sounds and utterances are generally the focus of speech communication research; little is known, however, about how the silence between speaker turns shades the meaning of the surrounding talk. We use an experimental protocol to test whether listeners’ perception of trouble in interaction (e.g., disagreemen...
Article
Full-text available
Whether or not categorical perception results from the operation of a special, language-specific, speech mode remains controversial. In this cross-language (Mandarin Chinese, English) study of the categorical nature of tone perception, we compared native Mandarin and English speakers' perception of a physical continuum of fundamental frequency cont...
Article
Full-text available
The present study explores the use of extrinsic context in perceptual normalization for the purpose of identifying lexical tones in Cantonese. In each of four experiments, listeners were presented with a target word embedded in a semantically neutral sentential context. The target word was produced with a mid level tone and it was never modified th...
Article
The present study examined the effect of native language background on the perception of American English tense and lax front unrounded vowels ([i] and [I]). These vowels are distinguishable according to both spectral (vowel quality) and temporal (vowel duration) properties. Nineteen native Russian and 12 native American English listeners identifie...
Article
Full-text available
Identification and discrimination of lexical tones in Cantonese were compared in the context of a traditional categorical perception paradigm. Three lexical tone continua were used: one ranging from low level to high level, one from high rising to high level, and one from low falling to high rising. Identification data showed steep slopes at catego...
Article
Full-text available
Listeners' auditory discrimination of vowel sounds depends in part on the order in which stimuli are presented. Such presentation order effects have been argued to be language independent, and to result from psychophysical (not speech- or language-specific) factors such as the decay of memory traces over time or increased weighting of later-occurri...
Article
Full-text available
The aim of this study was to determine if children with repaired cleft palate who demonstrate posterior placement of alveolar targets (e.g., /t(h)/ --> [k(h)]), known as Group P, differ from children with cleft palate without such an error pattern (Group NP) and from normally developing children without cleft palate (Group N) in the perception of /...
Article
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Five commonly used methods for determining the onset of voicing of syllable-initial stop consonants were compared. The speech and glottal activity of 16 native speakers of Cantonese with normal voice quality were investigated during the production of consonant vowel (CV) syllables in Cantonese. Syllables consisted of the initial consonants /ph/, /t...