A Picture May Be Worth 1,000 Words, but Is It Worth a Letter? Examining Whether the Choice of Label Affects the Perception of Speech Sounds.

PURPOSE: Researchers often use identification or goodness rating tasks to assess speech perception for different populations. These tasks provide useful information about a listener's willingness to accept a range of acoustically variable stimuli as belonging to the same category and also about assessing how stimuli that are labeled the same may not be perceived as equally good versions of a particular speech sound. Many methodological aspects of these simple tasks have been tested, but one aspect that has not is the choice of label. In this study, we examine response patterns to images versus letters, as studies with different populations (children vs. adults) or different methods (typical behavioral study vs. visual world paradigm) may vary in the type of label used. METHOD: Eighty-one adult listeners completed phoneme identification and goodness ratings tasks with either images of response options (a picture of a bear and a picture of a pear) or with letter labels (a capital B and P). RESULTS: The results suggest that choice of label does not alter performance within the tasks studied here. In addition, the results did show the expected finding that the slope of the response curve is steeper in an identification task than in a goodness rating task. CONCLUSION: These results suggest that it is possible to compare across studies that use different response options, a benefit to research and practice because letter labels can be used for nonimageable words and nonwords, whereas images may be best used for participants who are younger or have poorer reading skills.

Examining the Relationship Between Multiple Tests of Receptive Vocabulary.

PURPOSE: Numerous tasks have been developed to measure receptive vocabulary, many of which were designed to be administered in person with a trained researcher or clinician. The purpose of the current study is to compare a common, in-person test of vocabulary with other vocabulary assessments that can be self-administered. METHOD: Fifty-three participants completed the Peabody Picture Vocabulary Test (PPVT) via online video call to mimic in-person administration, as well as four additional fully automated, self-administered measures of receptive vocabulary. Participants also completed three control tasks that do not measure receptive vocabulary. RESULTS: Pearson correlations indicated moderate correlations among most of the receptive vocabulary measures (approximately r = .50-.70). As expected, the control tasks revealed only weak correlations to the vocabulary measures. However, subsets of items of the four self-administered measures of receptive vocabulary achieved high correlations with the PPVT (r > .80). These subsets were found through a repeated resampling approach. CONCLUSIONS: Measures of receptive vocabulary differ in which items are included and in the assessment task (e.g., lexical decision, picture matching, synonym matching). The results of the current study suggest that several self-administered tasks are able to achieve high correlations with the PPVT when a subset of items are scored, rather than the full set of items. These data provide evidence that subsets of items on one behavioral assessment can more highly correlate to another measure. In practical terms, these data demonstrate that self-administered, automated measures of receptive vocabulary can be used as reasonable substitutes of at least one test (PPVT) that requires human interaction. That several of the fully automated measures resulted in high correlations with the PPVT suggests that different tasks could be selected depending on the needs of the researcher. It is important to note the aim was not to establish clinical relevance of these measures, but establish whether researchers could use an experimental task of receptive vocabulary that probes a similar construct to what is captured by the PPVT, and use these measures of individual differences.

Spectral analysis of strident fricatives in cisgender and transfeminine speakersa).

The spectral features of /s/ and /ʃ/ carry important sociophonetic information regarding a speaker's gender. Often, gender is misclassified as a binary of male or female, but this excludes people who may identify as transgender or nonbinary. In this study, we use a more expansive definition of gender to investigate the acoustics (duration and spectral moments) of /s/ and /ʃ/ across cisgender men, cisgender women, and transfeminine speakers in voiced and whispered speech and the relationship between spectral measures and transfeminine gender expression. We examined /s/ and /ʃ/ productions in words from 35 speakers (11 cisgender men, 17 cisgender women, 7 transfeminine speakers) and 34 speakers (11 cisgender men, 15 cisgender women, 8 transfeminine speakers), respectively. In general, /s/ and /ʃ/ center of gravity was highest in productions by cisgender women, followed by transfeminine speakers, and then cisgender men speakers. There were no other gender-related differences. Within transfeminine speakers, /s/ and /ʃ/ center of gravity and skewness were not related to the time proportion expressing their feminine spectrum gender or their Trans Women Voice Questionnaire scores. Taken together, the acoustics of /s/ and /ʃ/ may signal gender group identification but may not account for within-gender variation in transfeminine gender expression.

Intelligibility as a measure of speech perception: Current approaches, challenges, and recommendations.

Intelligibility measures, which assess the number of words or phonemes a listener correctly transcribes or repeats, are commonly used metrics for speech perception research. While these measures have many benefits for researchers, they also come with a number of limitations. By pointing out the strengths and limitations of this approach, including how it fails to capture aspects of perception such as listening effort, this article argues that the role of intelligibility measures must be reconsidered in fields such as linguistics, communication disorders, and psychology. Recommendations for future work in this area are presented.

Teaching acoustic phonetics to undergraduates in communication sciences and disorders: Course structure and sample projects.

Virtually all undergraduate communication sciences and disorders programs require a course that covers acoustic phonetics. Students typically have a separate phonetics (transcription) course prior to taking the acoustic phonetics course. This paper describes a way to structure an acoustic phonetics course into two halves: a first half that focuses on the source, including basic acoustics (simple harmonic motion, harmonics), vocal fold vibration, modes of phonation, and intonation, and a second half that focuses on the filter, including resonance and tube models, vowel formants, and consonant acoustics. Thus, basic acoustic properties are interwoven with specific examples of speech-related acoustics. In addition, two projects that illustrate concepts from the two halves of the course (one on fundamental frequency and the other on vowel formants) are presented.

Phonotactic and lexical factors in talker discrimination and identification.

Previous research has shown that listeners are better at processing talker information in their native language compared to an unfamiliar language, a phenomenon known as the language familiarity effect. Several studies have explored two mechanisms that support this effect: lexical status and phonological familiarity. Further support for the importance of phonological knowledge comes from studies showing that participants with poorer reading skills perform worse on talker processing tasks. Previous research also suggested that speech perception in individuals with poor reading skills may be task dependent, with poorer performance on identification tasks compared to discrimination tasks. In the current study, we explore talker perception while manipulating lexicality (words, nonwords) and phonotactic probability (high, low) in participants who differ in reading ability and phonological working memory using a talker discrimination task (Experiment 1) and a talker identification task (Experiment 2). Results from these experiments revealed an effect of lexical status and phonotactic probability in both the discrimination and the identification tasks. Effects of phonological working memory were found only for the identification task, where participants with higher scores identified more talkers correctly. These results suggest that listeners use both phonological and lexical information when processing talker information. The task-modulated results show that listeners with poorer phonological working memory perform worse on talker identification tasks that tap into long-term memory representations, but not on discrimination tasks that can be completed with more peripheral processing. This may suggest a more general link between phonological working memory and learning talker categories.

Effect of Anchor Term on Auditory-Perceptual Ratings of Feminine and Masculine Speakers.

BACKGROUND: Studies investigating auditory perception of gender expression vary greatly in the specific terms applied to gender expression in rating scales. PURPOSE: This study examined the effects of different anchor terms on listeners' auditory perceptions of gender expression in phonated and whispered speech. Additionally, token and speaker cues were examined to identify predictors of the auditory-perceptual ratings. METHOD: Inexperienced listeners (n = 105) completed an online rating study in which they were asked to use one of five visual analog scales (VASs) to rate cis men, cis women, and transfeminine speakers in both phonated and whispered speech. The VASs varied by anchor term (very female/very male, feminine/masculine, feminine female/masculine male, very feminine/not at all feminine, and not at all masculine/very masculine). RESULTS: Linear mixed-effects models revealed significant two-way interactions of gender expression by anchor term and gender expression by condition. In general, the feminine female/masculine male scale resulted in the most extreme ratings (closest to the end points), and the feminine/masculine scale resulted in the most central ratings. As expected, for all speakers, whispered speech was rated more centrally than phonated speech. Additionally, ratings of phonated speech were predicted by mean fundamental frequency (f o) within each speaker group and by smoothed cepstral peak prominence in cisgender speakers. In contrast, ratings of whispered speech, which lacks an f o, were predicted by indicators of vocal tract resonance (second formant and speaker height). CONCLUSIONS: The current results indicate that differences in the terms applied to rating scales limit generalization of results across studies. Identifying the patterns across listener ratings of gender expression provide a rationale for researchers and clinicians when making choices about terms. Additionally, beyond f o and vocal tract resonance, predictors of listener ratings vary based on the anchor terms used to describe gender expression. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.19617564.

Differences in perceptual assimilation following training.

Learning to perceive non-native speech sounds is difficult for adults. One method to improve perception of non-native contrasts is through a distributional learning paradigm. Three groups of native-English listeners completed a perceptual assimilation task in which they mapped French vowels onto English vowel categories: Two groups (bimodal, unimodal distribution) completed a perceptual learning task for the French /œ/-/o/ contrast and a third completed no training. Both trained groups differed from the untrained group, but participants in the bimodal group showed a different perceptual mapping for the targeted /œ/ vowel, suggesting that the bimodal condition may maximize perception of non-native contrasts.

Effect of Phonation on Perception of Femininity/Masculinity in Transgender and Cisgender Speakers.

Many transwomen seek voice and communication therapy to support their transition from their gender assigned at birth to their gender identity. This has led to an increased need to examine the perception of gender and femininity/masculinity to develop evidence-based intervention practices. In this study, we explore the auditory perception of femininity/masculinity in normally phonated and whispered speech. Transwomen, ciswomen, and cismen were recorded producing /hVd/ words. Naïve listeners rated femininity/masculinity of a speaker's voice using a visual analog scale, rather than completing a binary gender identification task. The results revealed that listeners rated speakers more ambiguously in whispered speech than normally phonated speech. An analysis of speaker and token characteristics revealed that in the normally phonated condition listeners consistently use f0 to rate femininity/masculinity. In addition, some evidence was found for possible contributions of formant frequencies, particularly F2, and duration. Taken together, this provides additional evidence for the salience of f0 and F2 for voice and communication intervention among transwomen.

Acoustic differences between voiced and whispered speech in gender diverse speakers.

Whispered speech is a naturally produced mode of communication that lacks a fundamental frequency. Several other acoustic differences exist between whispered and voiced speech, such as speaking rate (measured as segment duration) and formant frequencies. Previous research has shown that listeners are less accurate at identifying linguistic information (e.g., identifying a speech sound) and speaker information (e.g., reporting speaker gender) from whispered speech. To further explore differences between voiced and whispered speech, acoustic differences were examined across three datasets (hVd, sVd, and ʃVd) and three speaker groups (ciswomen, transwomen, cismen). Consistent with previous studies, vowel duration was generally longer in whispered speech and formant frequencies were shifted higher, although the magnitude of these differences depended on vowel and gender. Despite the increase in duration, the acoustic vowel space area (measured either with a vowel quadrilateral or with a convex hull) was smaller in the whispered speech, suggesting that larger vowel space areas are not an automatic consequence of a lengthened articulation. Overall, these findings are consistent with previous literature showing acoustic differences between voiced and whispered speech beyond the articulatory change of eliminating fundamental frequency.

Re-Examining the Effect of Top-Down Linguistic Information on Speaker-Voice Discrimination.

The current study replicated and extended the results from a study conducted by Narayan, Mak, and Bialystok (2017) that found effects of top-down linguistic information on a speaker discrimination task by examining four conditions: rhymes (day-bay), compounds (day-dream), reverse compounds (dream-day), and unrelated words (day-bee). The original study found that participants were more likely to judge two words to be spoken by the same speaker if the words cohered lexically (created lexical compounds such as day-dream) or were phonologically related (rhymes, such as day-bay), but their study contained two limitations: (a) Same- and different-speaker trials were analyzed separately, which obscures effects of response bias, and (b) cross-gender pairs were used in the different-speaker trials, potentially inflating performance. The current study addresses these limitations by including only within-gender trials and by examining sensitivity and bias using signal detection theory. Our results not only provide support of the original study but also provide clear evidence that listeners are biased to judge two words as being produced by the same person when they share either phonological information (rhymes) or lexical-semantic coherence (compounds). Thus, the current study provides an important modified replication of previous research.

Training a non-native vowel contrast with a distributional learning paradigm results in improved perception and production.

Previous distributional learning research suggests that adults can improve perception of a non-native contrast more efficiently when exposed to a bimodal than a unimodal distribution. Studies have also suggested that perceptual learning can transfer to production. The current study tested whether the addition of visual images to reinforce the contrast and active learning with feedback would result in lcearning in both conditions and would transfer to gains in production. Native English-speaking adults heard stimuli from a bimodal or unimodal /o/-/œ/ continuum. No group differences were found on a discrimination task, possibly suggesting that the supports eliminated previously documented group differences. On an identification task, listeners in the bimodal group showed better performance than the unimodal group on the endpoint stimuli. Production results indicated that both groups showed increased Euclidean distance between the target vowels after training, suggesting that perceptual training improved production skills in both conditions. Contrary to expectations, degree of perception and production learning were not correlated. Together, these results suggest that a bimodal distribution may aid learning, but that adding images to reinforce the contrast and active learning to the training paradigm could mitigate disadvantages found previously for participants exposed to a unimodal distribution.

Language Ability and the Familiar Talker Advantage: Generalizing to Unfamiliar Talkers Is What Matters.

Purpose Previous studies with children and adults have demonstrated a familiar talker advantage-better word recognition for familiar talkers. The goal of the current study was to test whether this phenomenon is modulated by a child's language ability. Method Sixty children with a range of language ability were trained to learn the voices of 3 foreign-accented, German-English bilingual talkers and received feedback about their performance. Both before and after this talker voice training, children completed a spoken word recognition task in which they heard consonant-vowel-consonant words mixed with noise that were spoken by the 3 familiarized talkers and by 3 unfamiliar German-English bilinguals. Results Two findings emerged from this study: First, children with both higher and lower language ability performed similarly on the familiarized talkers. Second, children with higher language scores performed similarly on both the familiarized and unfamiliar talkers, whereas children with lower language scores performed worse on the unfamiliar talkers compared to familiar talkers, suggesting an inability to generalize to novel, unfamiliar talkers who spoke with a similar accent. Discussion Together, these findings indicate that children with higher language scores are able to generalize knowledge about foreign-accented talkers to help spoken word recognition for novel talkers with the same accent. In contrast, children with lower language skills did not exhibit the same magnitude of generalization. This lack of generalization to similar talkers may mean that children with lower language skills are at a disadvantage in spoken language tasks because they are unable to process speech as well when listening to unfamiliar talkers.

Methodological considerations for interpreting the Language Familiarity Effect in talker processing.

The Language Familiarity Effect (LFE)-where listeners are better at processing talker-voice information in their native language than in an unfamiliar language-has received renewed attention in the past 10 years. Numerous studies have sought to probe the underlying causes of this advantage by cleverly manipulating aspects of the stimuli (using phonologically related languages, backwards speech, nonwords) and by examining individual differences across listeners (testing reading ability and pitch perception). Most of these studies find evidence for the importance of phonological information or phonological processing as a supporting mechanism for the LFE. What has not been carefully examined, however, are how other methodological considerations such as task effects and stimulus length can change performance on talker-voice processing tasks. In this review, I provide an overview of the literature on the LFE and examine how methodological decisions affect the presence or absence of the LFE. This article is categorized under: Linguistics > Language in Mind and Brain Psychology > Language.

Does Implicit Voice Learning Improve Spoken Language Processing? Implications for Clinical Practice.

Purpose: In typical interactions with other speakers, including a clinical environment, listeners become familiar with voices through implicit learning. Previous studies have found evidence for a Familiar Talker Advantage (better speech perception and spoken language processing for familiar voices) following explicit voice learning. The current study examined whether a Familiar Talker Advantage would result from implicit voice learning. Method: Thirty-three adults and 16 second graders were familiarized with 1 of 2 talkers' voices over 2 days through live interactions as 1 of 2 experimenters administered standardized tests and interacted with the listeners. To assess whether this implicit voice learning would generate a Familiar Talker Advantage, listeners completed a baseline sentence recognition task and a post-learning sentence recognition task with both the familiar talker and the unfamiliar talker. Results: No significant effect of voice familiarity was found for either the children or the adults following implicit voice learning. Effect size estimates suggest that familiarity with the voice may benefit some listeners, despite the lack of an overall effect of familiarity. Discussion: We discuss possible clinical implications of this finding and directions for future research.

Short-term implicit voice-learning leads to a Familiar Talker Advantage: The role of encoding specificity.

Whereas previous research has found that a Familiar Talker Advantage-better spoken language perception for familiar voices-occurs following explicit voice-learning, Case, Seyfarth, and Levi [(2018). J. Speech, Lang., Hear. Res. 61(5), 1251-1260] failed to find this effect after implicit voice-learning. To test whether the advantage is limited to explicit voice-learning, a follow-up experiment evaluated implicit voice-learning under more similar encoding (training) and retrieval (test) conditions. Sentence recognition in noise improved significantly more for familiar than unfamiliar talkers, suggesting that short-term implicit voice-learning can lead to a Familiar Talker Advantage. This paper explores how similarity in encoding and retrieval conditions might affect the acquired processing advantage.

Generalization of Phonetic Detail: Cross-Segmental, Within-Category Priming of VOT.

The current study examined whether fine-grained phonetic detail (voice onset time (VOT)) of one segment (/p/ or /k/) generalizes to a different segment (/t/) within the same natural class. Two primes were constructed to exploit the natural variation of VOT: a velar stop followed by a high vowel (keen) resulting in a naturally long VOT and a labial stop followed by a low vowel (pan) resulting in a naturally shorter VOT. Two experiments were conducted, one in which the speakers produced both the prime and the target, and a second in which the speakers heard the primes and then produced the targets. In Experiment 1, VOTs for initial /t/ were shorter following pan than following keen. In Experiment 2 where participants heard the primes, priming was found only when the primes had unexpected relative VOT values (short for keen and long for pan). These results provide evidence for cross-segmental generalization of phonetic detail and also suggest that natural, within-category variability is encoded during language processing.

Talker familiarity and spoken word recognition in school-age children.

Research with adults has shown that spoken language processing is improved when listeners are familiar with talkers' voices, known as the familiar talker advantage. The current study explored whether this ability extends to school-age children, who are still acquiring language. Children were familiarized with the voices of three German-English bilingual talkers and were tested on the speech of six bilinguals, three of whom were familiar. Results revealed that children do show improved spoken language processing when they are familiar with the talkers, but this improvement was limited to highly familiar lexical items. This restriction of the familiar talker advantage is attributed to differences in the representation of highly familiar and less familiar lexical items. In addition, children did not exhibit accent-general learning; despite having been exposed to German-accented talkers during training, there was no improvement for novel German-accented talkers.

Individual differences in learning talker categories: the role of working memory.

The current study explores the question of how an auditory category is learned by having school-age listeners learn to categorize speech not in terms of linguistic categories, but instead in terms of talker categories (i.e., who is talking). Findings from visual-category learning indicate that working memory skills affect learning, but the literature is equivocal: sometimes better working memory is advantageous, and sometimes not. The current study examined the role of different components of working memory to test which component skills benefit, and which hinder, learning talker categories. Results revealed that the short-term storage component positively predicted learning, but that the Central Executive and Episodic Buffer negatively predicted learning. As with visual categories, better working memory is not always an advantage.

The development of language-specific and language-independent talker processing.

PURPOSE: In this study, the authors aimed to investigate how differences in language ability relate to differences in processing talker information in the native language and an unfamiliar language by comparing performance for different ages and for groups with impaired language. METHOD: Three groups of native English listeners with typical language development (TLD; ages 7-9, ages 10-12, adults) and 2 groups with specific language impairment (SLI; ages 7-9, ages 10-12) participated in the study. Listeners heard pairs of words in both English and German (unfamiliar language) and were asked to determine whether the words were produced by the same or different talkers. RESULTS: In English, talker discrimination improved with age. In German, performance improved with age for the school-age children but was worse for adult listeners. No differences were found between TLD and SLI children. CONCLUSION: These results show that as listeners' language skills develop, there is a trade-off between more general perceptual abilities useful for processing talker information in any language and those that are relevant to their everyday language experiences and, thus, tied to the phonology. The lack of differences between the children with and without language impairments suggests that general auditory processing may be intact in at least some children with SLI.