Lexical Diversity, Lexical Sophistication, and Predictability for Speech in Multiple Listening Conditions

When talkers anticipate that a listener may have difficulty understanding their speech, they adopt a speaking style typically described as “clear speech.” This speaking style includes a variety of acoustic modifications and has perceptual benefits for listeners. In the present study, we examine whether clear speaking styles also include modulation of lexical items selected and produced during naturalistic conversations. Our results demonstrate that talkers do, indeed, modulate their lexical selection, as measured by a variety of lexical diversity and lexical sophistication indices. Further, the results demonstrate that clear speech is not a monolithic construct. Talkers modulate their speech differently depending on the communication situation. We suggest that clear speech should be conceptualized as a set of speaking styles, in which talkers take the listener and communication situation into consideration

Multidimensional signals and analytic flexibility: Estimating degrees of freedom in human speech analyses

Recent empirical studies have highlighted the large degree of analytic flexibility in data analysis which can lead to substantially different conclusions based on the same data set. Thus, researchers have expressed their concerns that these researcher degrees of freedom might facilitate bias and can lead to claims that do not stand the test of time. Even greater flexibility is to be expected in fields in which the primary data lend themselves to a variety of possible operationalizations. The multidimensional, temporally extended nature of speech constitutes an ideal testing ground for assessing the variability in analytic approaches, which derives not only from aspects of statistical modeling, but also from decisions regarding the quantification of the measured behavior. In the present study, we gave the same speech production data set to 46 teams of researchers and asked them to answer the same research question, resulting insubstantial variability in reported effect sizes and their interpretation. Using Bayesian meta-analytic tools, we further find little to no evidence that the observed variability can be explained by analysts’ prior beliefs, expertise or the perceived quality of their analyses. In light of this idiosyncratic variability, we recommend that researchers more transparently share details of their analysis, strengthen the link between theoretical construct and quantitative system and calibrate their (un)certainty in their conclusions

Listeners beware: Speech production may be bad for learning speech sounds

Available online 14 November 2015Spoken language requires individuals to both perceive and produce speech. Because both processes access lexical and sublexical representations, it is commonly assumed that perception and production involve cooperative processes. However, few studies have directly examined the nature of the relationship between the two modalities, particularly how producing speech influences speech perception. In a series of experiments, we examine the counter-intuitive finding that learning perceptual representations can be disrupted by producing tokens during training. We investigate whether this disruption can be alleviated by prior experience with the speech sounds, and whether the cause of the disruption is production of the particular sound being learned, or is a more general conflict between the production system and the system that develops new perceptual representations. Our results paint a more competitive relationship between perception and production than might be assumed and suggest that both demands inherent to production and cognitive demands modulate this relationship

Just give it time: Differential effects of disruption and delay on perceptual learning

Published online: 11 March 2022Speech perception and production are critical skills when acquiring a new language. However, the nature of the relationship between these two processes is unclear, particularly for non-native speech sound contrasts. Although it has been assumed that perception and production are supportive, recent evidence has demonstrated that, under some circumstances, production can disrupt perceptual learning. Specifically, producing the to-be-learned contrast on each trial can disrupt perceptual learning of that contrast. Here, we treat speech perception and speech production as separate tasks. From this perspective, perceptual learning studies that include a production component on each trial create a task switch. We report two experiments that test how task switching can disrupt perceptual learning. One experiment demonstrates that the disruption caused by switching to production is sensitive to time delays: Increasing the delay between perception and production on a trial can reduce and even eliminate disruption of perceptual learning. The second experiment shows that if a task other than producing the to-be-learned contrast is imposed, the task-switching component of disruption is not influenced by a delay. These experiments provide a new understanding of the relationship between speech perception and speech production, and clarify conditions under which the two cooperate or compete.This work was supported by the National Science Foundation Grants BCS-1734166, BCS-1941739, by Economic and Social Research Council (UK) Grant #ES/R006288/1, Ministerio de Ciencia E Inovacion (Spain) Grant # PSI2017-82563-P, by Ayuda Centro de Excelencia Severo Ochoa (Spain) SEV-2015-0490, and by Grant PIBA18-29 from the Basque Governmen

Listeners beware: Speech production may be bad for learning speech sounds

Available online 14 November 2015Spoken language requires individuals to both perceive and produce speech. Because both processes access lexical and sublexical representations, it is commonly assumed that perception and production involve cooperative processes. However, few studies have directly examined the nature of the relationship between the two modalities, particularly how producing speech influences speech perception. In a series of experiments, we examine the counter-intuitive finding that learning perceptual representations can be disrupted by producing tokens during training. We investigate whether this disruption can be alleviated by prior experience with the speech sounds, and whether the cause of the disruption is production of the particular sound being learned, or is a more general conflict between the production system and the system that develops new perceptual representations. Our results paint a more competitive relationship between perception and production than might be assumed and suggest that both demands inherent to production and cognitive demands modulate this relationship

The phonetics of vowel intrusion in Sgi Bara

We provide a phonetic examination of intrusive vowels in Sgi Bara [jil]. These vowels are inserted in predictable places, and their quality (either [i], [ɨ], or [u]) is also predictable, so they are not considered phonemic. We demonstrate that they differ from phonemic vowels in their duration, being shorter; and in their articulation, being more peripheral; but not in their intensity. We then demonstrate how this phonetic understanding of the difference between intrusive and phonemic vowels can be used to answer phonological questions about Sgi Bara. We offer two case studies: phonologically ambiguous sequences of high vowels, and frequent two-word combinations that may be univerbating. The results confirm the existence of a distinction between intrusive and phonemic vowels

Performance pay and non-native language comprehension: Can we learn to understand better when we’re paid to listen?

Non-native speech is difficult for native listeners to understand. While listeners can learn to understand non-native speech after exposure, it is unclear how to optimize this learning. Experimental subjects transcribed non-native speech and were paid either a flat rate or based on their performance. Participants who were paid based on performance demonstrated improved performance overall and faster learning than participants who were paid a flat rate. These results suggest that exposure alone is not sufficient to optimize learning of non-native speech and that current models of this process must be revised to account for the effects of motivation and incentive

How Good Does This Sound? Examining Listeners’ Second Language Proficiency and Their Perception of Category Goodness in Their Native Language

Language learners often transfer the sounds and prosody of their native language into their second language, but this influence can also flow in the opposite direction, with the second language influencing the first. Among other variables, language proficiency is known to affect the degree and directionality of cross-linguistic influence. However, little is known about how second language learning affects listeners’ perception of their native language. To begin addressing this gap, we examined the relationship between learners’ second language proficiency and their category goodness ratings in their native language. Thirty-nine English-speaking learners of Spanish listened to English words that began with voiced and voiceless stop consonants and were asked to rate how well the word represented the intended word on a 5-point scale. To create a voicing continuum, we manipulated the voice onset time of the word-initial stop in each target item from 125 ms of prevoicing to 100 ms of aspiration, in 25 ms steps. Proficiency did not affect the perception of voiced targets, but both proficiency and L2 stop production affected the perception of voiceless targets

Exploring effects of brief daily exposure to unfamiliar accent on listening performance and cognitive load

Introduction: Listeners rapidly “tune” to unfamiliar accented speech, and some evidence also suggests that they may improve over multiple days of exposure. The present study aimed to measure accommodation of unfamiliar second language- (L2-) accented speech over a consecutive 5-day period using both a measure of listening performance (speech recognition accuracy) and a measure of cognitive load (a dual-task paradigm). Methods: All subjects completed a dual-task paradigm with L1 and L2 accent on Days 1 and 5, and were given brief exposure to either L1 (control group) or unfamiliar L2 (training groups) accent on Days 2–4. One training group was exposed to the L2 accent via a standard speech transcription task while the other was exposed to the L2 accent via a transcription task that included implicit feedback (i.e., showing the correct answer after each trial). Results: Although overall improvement in listening performance and reduction in cognitive load were observed from Days 1 to 5, our results indicated neither a larger benefit for the L2 accent training groups compared to the control group nor a difference based on the implicit feedback manipulation. Discussion: We conclude that the L2 accent trainings implemented in the present study did not successfully promote long-term learning benefits of a statistically meaningful magnitude, presenting our findings as a methodologically informative starting point for future research on this topic.</p

Rapid adaptation to non-native speech is impaired in cochlear implant users.

To examine difficulties experienced by cochlear implant (CI) users when perceiving non-native speech, intelligibility of non-native speech was compared in conditions with single and multiple alternating talkers. Compared to listeners with normal hearing, no rapid talker-dependent adaptation was observed and performance was approximately 40% lower for CI users following increased exposure in both talker conditions. Results suggest that lower performance for CI users may stem from combined effects of limited spectral resolution, which diminishes perceptible differences across accents, and limited access to talker-specific acoustic features of speech, which reduces the ability to adapt to non-native speech in a talker-dependent manner