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"Among the most common occupations, schooteachers are the ones who experience the most changes throughout their career. Considering this, the present study aims to verify whether dysphonia in three different degrees may compromise the speech intelligibility of schoolteachers in the classroom. Overall, 39 students, average age 10 years, randomly selected from a public school in the Federal District, Brazil (Distrito Federal, Brasil) performed a transcription task of 20 sentences spoken by four distinct female voices in a classroom, one with a control voice (normal), another with mild dysphonia, 1 with moderate dysphonia and another with severe dysphonia. None of the voices in the study presented changes, neither in fluency nor articulation nor neurological changes. The sentences were previously recorded in an acoustically treated booth, with a microphone on a pedestal 5 cm away from the speaker's mouth. For each sentence to be recorded, the speech model was provided by the speech therapist and then repeated by the speaker according to the model. Each voice recorded 5 different sentences, phonetically balanced and with equivalent number of words. The students included in the study underwent auditory, auditory processing, sequential memory for verbal sounds and sound source location tests, fulfilling the normality criteria. They also did not have neurological or motor disorders or learning, speech or language disorders. Academic success was also taken into account. For the experiment, a speaker was placed in front of the classroom, 1 m from the wall and 1 m from the floor, and students were randomly assigned to the classroom seats. After listening to each sentence, some time was assigned for its transcription by each student. The occurrence of errors was higher in voices with moderate and severe dysphonia, in which a significant difference was found (P ≤0.003) showing that voices with moderate and severe dysphonia were less intelligible than the normal voice (control voice). No difference was found between the normal voice and the mild dysphonic voice. Binary logistic regression analysis also showed that students had a 2.55 times higher chance of making mistakes with moderate dysphonic voice (P ≤0.011), and that this chance was 3.06 times greater for severe dysphonic voice (P ≤0.002) when compared to the normal voice (control voice). Conclusion: Moderate and severe dysphonia in the voices of schoolteachers interferes with the intelligibility of students, and the greater the degree of dysphonia of the teacher, the greater the chance that the student will make intelligibility errors." [ABSTRACT FROM AUTHOR]

Canteens usually have critical acoustic conditions resulting from the need to maximize the number of occupants while minimizing volume. Thus, in the absence of specific sound absorbing treatments, very high sound pressure levels are usually observed resulting in significant impairment of communication (with increased vocal effort of speakers and reduced speech intelligibility), and dangerously high exposure levels for workers. The present paper reports acoustic measurements carried out in a nursery school canteen having a volume of 212 m3 and seating about 50 children, and two primary school canteens having volumes of 656 m3 (seating 150 children) and 367 m3 (seating 107 children). Reverberation time was measured in each room as well as sound pressure levels during peak occupation (averaged over 15-minute intervals), resulting in A-weighted sound pressure levels spanning between 81 dB (in the nursery school) and 90 dB in the primary schools. Starting from the observed values, considerations about the group-size of the occupants as a function of age were made, and recommendations were finally given to guide the acoustic correction of similar spaces. • Nursery and primary school canteens may be very noisy due to Lombard effect. • Reduced volume and room height are critical issues. • Exposure levels suggest possible risks for long-term occupants. • Existing models to predict noise level as a function of occupancy were applied. • Alternative formula to design acoustic treatments is proposed. [ABSTRACT FROM AUTHOR]

• The impact of visual cues on the intelligibility of foreign-accented speech for native listeners is studied. • The audiovisual benefit of visually salient cues varies across vowel features and speaker L1. • Lip-rounding in French productions of /ɔː/ and /ə/ have a smaller, or negative AV benefit, compared to English speakers. • French productions showed inappropriate visual cues for L2 contrasts (/æ ʌ ɑː/) not present in the L1. • The influence of L1 visual gestures on L2 production may negatively affect intelligibility. This study examines how visual cues impact the intelligibility of foreign-accented speech for native listeners. English CVC words with vowels involving salient (e.g., lip-spreading for /iː/) and non-salient visual cues (neutral lips for /ɪ/) produced by two French speakers and a native English control, were presented to native English listeners who identified the word heard. Tokens were presented in both auditory-only and audiovisual (AV) mode in cafeteria noise at −15 dB SNR. The visual cues analysed were lip spreading, lip rounding, jaw opening and tongue frontness in vowels, as well as lip-rounding in schwa. Visually salient cues improved vowel intelligibility, compared to non-visual cues, but the audiovisual benefit varied across vowel features and speaker groups. The presence of lip-spreading for /iː/ (vs /ɪ/) and jaw-opening for /æ/ (vs /ɪ/) enhanced intelligibility (i.e., larger AV benefit) for both speaker groups. However, compared to the English speaker, lip-rounding in /ɔː/ and /ə/ produced by French speakers (likely accompanied by lip protrusion) had a smaller, or negative AV benefit. These results suggest that the influence of L1 gestures on L2 production may reduce or negatively affect intelligibility. Furthermore, French productions of /ɑː/ exhibited unusually high AV benefits, suggesting an extreme jaw-opening for this vowel in an attempt to distinguish between L2 contrasts (/æ ʌ ɑː/) not present in the L1. [ABSTRACT FROM AUTHOR]

• Intelligibility quantified with percent words correct and fuzzy string matching. • Two pronunciation distance metrics predicted intelligibility for nine accents. • Stronger pronunciation distance effects for more difficult listening conditions. Unfamiliar accents can cause word recognition challenges, particularly in noisy environments, but few studies have incorporated quantitative pronunciation distance metrics to explain intelligibility differences across accents. To address this gap, intelligibility was measured for 18 talkers -- two from each of three first-language, one bilingual, and five second-language accents -- in quiet and two noise conditions. The relations between two edit distance metrics, which quantify phonetic differences from a reference accent, and intelligibility scores were assessed. Intelligibility was quantified through both fuzzy string matching and percent words correct. Both edit distance metrics were significantly related to intelligibility scores; a heuristic edit distance metric was the best predictor of intelligibility for both scoring methods. Further, there were stronger effects of edit distance as the listening condition increased in difficulty. Talker accent also contributed substantially to intelligibility models, but relations between accent and edit distance did not consistently pattern for the two talkers representing each accent. Frequency of production differences in vowels and consonants was negatively correlated with intelligibility, particularly for consonants. Together, these results suggest that significant amounts of variability in intelligibility across accents can be predicted by phonetic differences from the listener's home accent. However, talker- and accent-specific pronunciation features, including suprasegmental characteristics, must be quantified to fully explain intelligibility across talkers and listening conditions. [ABSTRACT FROM AUTHOR]

The potential for misunderstanding is ever-present in interaction, making it necessary that interactants have means for identifying and remediating troubles in understanding should they appear. These include not only practices for remediating others' misunderstandings, but also for remediating one's own misunderstandings. Using English and Dutch data, we analyse a practice that participants use for remediating misapprehensions on their part of some prior talk or given state-of-affairs, where the speaker first indexes a change-of-state and then explicates their misapprehension with "I thought (that) X" or "ik dacht dat X". In doing so the speakers disclose themselves to have misapprehended some talk or state-of-affairs and by so doing 're-apprehended' the 'actual' talk or 'correct' state-of-affairs, while also accounting for any action or conduct predicated on that misapprehension. • We investigate a remedial practice used in Dutch and English-speaking settings. • The practice is composed of a change-of-state followed by an " ik dacht/I thought "-turn. • The practice works by disclosing a misapprehension of a prior trouble-source. • The disclosure accounts for any next action predicated on the misapprehension. • The practice shows its speaker to have re-apprehended the trouble-source. [ABSTRACT FROM AUTHOR]

• Degree of foreign accent and intelligibility are weakly related. • A segmental analysis provides an explanatory basis. • Some strongly-accented segments, but not all, lead to a drop in intelligibility. • Intelligibility loss is linked to the segments' status in the native language. The relationship between strength of foreign accent and intelligibility is not straightforward. This relationship resists a simple characterisation due in part to the multiplicity of cues that carry accent in the word- and sentence-level materials typically used in the study of accent. One of the principal conveyors of accent is the phonetic segment. The current study attempts to isolate this segmental contribution to foreign accent and consequently measure the relationship between segmental accent and intelligibility for listeners with differing linguistic correspondence to the target and accented language. English, Spanish and Czech listeners identified English words in which the initial consonant was either intact, or had been replaced by a Spanish-accented counterpart; in a second task, they rated the accent strength of the same tokens. All speech material was produced by an English-Spanish bilingual talker. Overall, Spanish listeners displayed a smaller loss of intelligibility due to the accented segment than native English listeners, while the Czech cohort experienced the largest intelligibility loss. However, the relationship between accent strength and intelligibility loss was not linear, varying with phoneme identity and its role in a listener's first language. These findings suggest that how accented and intelligible a sound is depends strongly on the interactions between the phonological systems of speakers and listeners. [ABSTRACT FROM AUTHOR]

• We compared native English and non-native (Dutch) Lombard and plain speech. • Canadian, Dutch and Spanish listeners participated in an intelligibility experiment. • Both native and non-native Lombard speech resulted in a Lombard benefit. • A Lombard benefit was evident for both native and non-native listeners. • Energetic masking release partially accounted for the Lombard benefit. Speech produced in noise (Lombard speech) is more intelligible than speech produced in quiet (plain speech). Previous research on the Lombard intelligibility benefit focused almost entirely on how native speakers produce and perceive Lombard speech. In this study, we investigate the size of the Lombard intelligibility benefit of both native (American-English) and non-native (native Dutch) English for native and non-native listeners (Dutch and Spanish). We used a glimpsing metric to measure the energetic masking potential of speech, which predicted that both native and non-native Lombard speech could withstand greater amounts of masking to a similar extent, compared to plain speech. In an intelligibility experiment, native English, Spanish, and Dutch listeners listened to the same words, mixed with noise. While the non-native listeners appeared to benefit more from Lombard speech than the native listeners did, each listener group experienced a similar benefit for native and non-native Lombard speech. Energetic masking, as captured by the glimpsing metric, only accounted for part of the Lombard benefit, indicating that the Lombard intelligibility benefit does not only result from a shift in spectral distribution. Despite subtle native language influences on non-native Lombard speech, both native and non-native speech provides a Lombard benefit. [ABSTRACT FROM AUTHOR]

This study focuses on identifying effective features for controlling speech to increase speech intelligibility under adverse conditions. Previous approaches either cancel noise throughout speech presentation or preprocess speech by controlling its intensity and/or spectra. Among them, a method based on modulation transfer function theory, inverting the environmental effects to anticipate attenuation of speech modulation spectrum, shows excellent potential due to its systematic and explicit derivation of intelligibility enhancement against environmental smears. However, strictly following the inverse modulation transfer function is dangerous and inefficient as important speech features can be damaged, and it costs lots of energy to boost all smeared regions. This study takes a different approach: analyzing the relations of smeared modulation spectra by the environments for intelligibility to extract effective modifying features. First, we conduct listening tests for intelligibility in noise with different types of enhanced speech. Next, we extract acoustic and modulation frequency components in the smeared modulation spectra by noise showing high correlation with intelligibility scores. Finally, we examine the intelligibility benefits of modifying these components by performing listening tests. The results show that these components effectively increase intelligibility by at most 18%, which demonstrates that our concept is valid. • Our method increases intelligibility and preserves naturalness of speech in adverse environments. • It is based on modulation spectrum (MS) and modulation transfer function (MTF) concepts. • Our MS and MTF are two dimensional spectra with the axes of acoustic and modulation frequencies. • MS of plain speech are modified by optimal two-dimensional filters (2-D filters) to obtain intelligible and natural speech in any environment. • The 2-D filters are constructed from analyzing MS of enhanced speech, MTF of environments and subjective experiment results. • We could increase intelligibility for plain speech under different noisy reverberant conditions by about 18%. [ABSTRACT FROM AUTHOR]

Computational modeling plays an increasingly important role in neuroscience, highlighting the philosophical question of how computational models explain. In the particular case of neural network models, concerns have been raised about their intelligibility, and how these models relate (if at all) to what is found in the brain. We claim that what makes a system intelligible is an understanding of the dependencies between its behavior and the factors that are responsible for that behavior. In biology, many of these dependencies are naturally "top-down", as ethological imperatives interact with evolutionary and developmental constraints under natural selection to produce systems with capabilities and behaviors appropriate to their evolutionary needs. We describe how the optimization techniques used to construct neural network models capture some key aspects of these dependencies, and thus help explain why brain systems are as they are — because when a challenging ecologically-relevant goal is shared by a neural network and the brain, it places constraints on the possible mechanisms exhibited in both kinds of systems. The presence and strength of these constraints explain why some outcomes are more likely than others. By combining two familiar modes of explanation — one based on bottom-up mechanistic description (whose relation to neural network models we address in a companion paper) and the other based on top-down constraints, these models have the potential to illuminate brain function. [ABSTRACT FROM AUTHOR]

• Audience Response System (ARS)-based scores of acceptability are valid. • Listeners react more often to disruption of acceptability than to unintelligibility. • Panels of 6-10-year-old children provide valid and reliable scores of acceptability. • SLPs and other adults provide similar scores; children react less frequently. • ARS-based evaluations may be useful also in other areas of speech research. We explore the validity and reliability of an Audience Response Systems (ARS)-based measure of acceptability, applied to speech produced by children with speech sound disorder (SSD). We further explore how the suggested measure relates to an ARS-based measure of intelligibility. Finally, we explore potential differences between speech-language pathologists (SLPs), untrained adults, and children in their assessments. Fifty-three listeners participated in ARS-based assessments of acceptability and intelligibility: 19 SLPs, 18 untrained adults, and 16 children (aged 6-10 years). The listeners assessed speech samples collected from 14 children with SSD and 2 children with typical speech. The validity of the ARS-based acceptability measure was investigated through correlation analyses with reference to rating-based acceptability, as well as to measures of intelligibility and speech proficiency. The ARS-based acceptability measure correlated strongly with all assumed related measures. Listeners reacted more often to affected acceptability than to unintelligibility. Child listeners reacted less frequently to acceptability disruption than the SLPs and untrained adults. ARS-based assessment of acceptability provides a valid and reliable measure of acceptability. The ARS-based methodology captures an anticipated pattern where listeners react more often to disruptions of acceptability than to unintelligibility. Children appear less sensitive to traits signaling SSD than SLPs and other adults are; however, replication is required to establish this for sure. [ABSTRACT FROM AUTHOR]

To analyze the performance of cochlear implants in French patients aged 65 and over, implanted between 2012 and 2016, using data from the French national registry for cochlear implants (EPIIC). The French national registry incorporates patient data from before implantation and for three years after implantation, stratified in different age groups (18–39, 40–64 years, 65–74 years and > 75 years). Here, we assessed the latter two categories. Hearing was assessed using mono- and disyllabic words in a silent background. The Category of Auditory Performance (CAP) scale was also implemented and subjects took the Abbreviated Profile of Hearing Aid Benefit (Aphab) questionnaire. The population aged over 65 accounted for 38% (n = 1193) of the 3178 adult implanted patients. The performance for mono- and disyllabic words in silence, the CAP scores and the APHAB questionnaire answers for ease of communication, background noise and reverberation were dramatically improved at one year post-implantation (P < 0.0001 for each score) and remained stable between one and three years thereafter. The percentage improvement was similar across all age groups. The scores for loud-noise intolerance did not change after cochlear implantation in any age group. Cochlear implants improve hearing and communication in subjects aged 65 and over, with comparable efficiency to that achieved in younger subjects. Cochlear implantation should thus be proposed whenever hearing aids provide only limited benefit. However, between 2012 and 2016, cochlear implantation was given to less than 1% of the French population aged 65 and over with profound deafness. [ABSTRACT FROM AUTHOR]

Communicating in noisy settings can be difficult due to interference and environmental noise, which can impact intelligibility for those with hearing impairments and those with normal hearing threshold. Speech intelligibility is commonly assessed in audiology through speech audiometry in quiet environments. Nevertheless, this test may not effectively assess hearing challenges in noisy environments, as total silence is rare in daily activities. A recently patented method, known as the SRT50 FAST, has been developed for conducting speech audiometry in noise. This new method enables the acceleration and simplification of free field speech audiometry tests involving competition noise. This study aims to establish normative scores and standardize the SRT50 FAST method as a test for evaluating speech perception in noise in pediatric patients. The study included 30 participants with normal hearing, consisting of 11 females and 19 males, ranging in age from 6 to 11 years. A series of speech audiometry tests were conducted to determine the speech reception threshold 50% (SRT50) in competing conditions. This included testing both the fast mode (SRT50 FAST) currently being studied and the traditional method (SRT50 CLASSIC). The SRT50, or Signal to Noise Ratio (SNR) at which 50% of speech recognition occurred, was investigated for both methods. The mean SRT50 FAST test score was −2.69 (SD = 3.15). The dataset exhibited a normal distribution with values ranging from 3.60 to −8.60. Since the scores are expressed in SRT, higher scores indicate poorer performance. We have established a threshold of 3.60 as the upper limit of the normal range, therefore, patients with scores above this threshold are considered to have abnormal results. This study aimed to establish normative data for the evaluation of free field speech in noise recognition using the SRT50 FAST method in the pediatric population. This method accurately investigates the necessary signal-to-noise ratio for achieving 50% recognition scores with bisyllabic words in a quick manner. The ultimate objective is to employ this test to identify the optimal configuration of hearing rehabilitation devices, particularly for pediatric patients with hearing aids and/or cochlear implants. Additionally, it can be used to assess pediatric patients with unilateral hearing loss. [ABSTRACT FROM AUTHOR]

• Higher speech intensity and lower speech rates improve automatic speech recognition accuracy. • Arab ESL teachers and students give more attention to pronunciation errors that do not affect intelligibility. • Arabic-influenced ESL pronunciation errors affecting automatic speech recognition are related to consonant clusters and sounds with adjacent places of articulation that are likely to appear in minimal pairs (as in temper vs. temple). The present study examines the impact of Arab speakers' phonological and prosodic features on the accuracy of automatic speech recognition (ASR) of non-native English speech. The authors first investigated the perceptions of 30 Egyptian ESL teachers and 70 Egyptian university students towards the L1 (Arabic)-based errors affecting intelligibility and then carried out a data analysis of the ASR of the students' English speech to find out whether the errors investigated resulted in intelligibility breakdowns in an ASR setting. In terms of the phonological features of non-native speech, the results showed that the teachers gave more weight to pronunciation features of accented speech that did not actually hinder recognition, that the students were mostly oblivious to the L2 errors they made and their impact on intelligibility, and that L2 errors which were not perceived as serious by both teachers and students had negative impacts on ASR accuracy levels. In regard to the prosodic features of non-native speech, it was found that lower speech rates resulted in more accurate speech recognition levels, higher speech intensity led to less deletion errors, and voice pitch did not seem to have any impact on ASR accuracy levels. The study, accordingly, recommends training ASR systems with more non-native data to increase their accuracy levels as well as paying more attention to remedying non-native speakers' L1-based errors that are more likely to impact non-native automatic speech recognition. [ABSTRACT FROM AUTHOR]

• Disciplined body refers to bodily movements designed and shaped for the machine. • Disciplining the body involves recipient-designing movements for the machine. • Participants endogenously display a sensitivity towards machine's recognition. • Participants attribute the abilities to see and recognize to the machine. • Players need to discipline their bodies and produce machine-designed movements. This study examines disciplined body in video game playing activities in which players produce their game moves with their bodies. Disciplined body refers to particularly designed bodily movements, orienting to their recognizability by the machine. Drawing on ethnomethodology and conversation analysis, this study demonstrates that participants endogenously display a sensitivity towards machine's recognition, through which they point to a need for players to discipline their bodies and produce machine-designed movements. Disciplining the body involves producing the game movements in particular forms required by the machine, calibrating the movements to the constraints of the machine, and timing the movements in coordination with the unfolding games. The analysis provides insights for reflecting on the relations between humans and machines and in particular how the former adapts to the latter. Participants attribute a specific form of agency to the machine to see and recognize the player movements. This necessitates the players to perform their game movements with specific qualities, which deviates from the "natural" human body, arguably leading to dehumanization. This study is based on video-recorded data in which participants speak Turkish. [ABSTRACT FROM AUTHOR]

Literature to date describes people with Profound and Multiple Learning Disabilities (PMLD) as pre-linguistic. In contrast, this study explores the existence and use of meaningful sub vocal (SV) language by twenty PMLD participants. The SV utterances of 20 PMLD participants were recorded and amplified. Recordings were investigated for evidence of language content and structure, listener intelligibility, and acoustic and phonetic features relative to normal speech and whisper. Language content and structure was identified. Listener intelligibility was demonstrated. Acoustic and phonetic features relative to normal speech and whisper were evident. Twenty PMLD participants produced meaningful SV language intelligible to listeners. This study requires further robust research to fully confirm its findings but highlights implications for clinical practice and for understanding of PMLD communication competencies. This paper is accompanied by audio samples and transcriptions of recorded utterances to demonstrate the SV language produced by the participants. The quality of the samples varies due to the difficulties in recording SV utterances and the difficulties for participants in articulating clearly. This is not normal speech, but it is normal language. The listener may need to replay samples where the quality of the recording is poor. [ABSTRACT FROM AUTHOR]

Abstract A crucial stage in unsupervised speech enhancement algorithm is the estimation of noise related parameters which usually needs prior models for noise. However, estimation of such parameters is a challenging task at low signal-to-noise ratios or in nonstationary noisy environments. In this paper, without knowing the prior models, an unsupervised and iterative speech enhancement algorithm is proposed which assumes speech spectrogram and its temporal gradient as sparse components. The quasi-harmonic description of the speech signals justifies this assumption. The speech enhancement is performed by decomposing the spectrogram of noisy speech into sparse matrix, enforcing the sparsity and temporal gradient regularizations. The Kullback–Leibler divergence is incorporated to minimize the distance between the observation and reconstructed components with nonnegativity constraints. Alternating direction method of multipliers is used to optimize the algorithm. The proposed algorithm is different from many speech enhancement approaches as it reduces background noise in an uncomplicated manner without need of a noise estimation algorithm to find noise-only excerpt. In addition, the proposed algorithm obtains an improved performance in adverse environments without knowing the exact distribution of noise. The experimental results demonstrate that the proposed algorithm outperforms the competing algorithms in terms of the speech quality and intelligibility. Moreover, the composite objective measure reinforced better performance in terms of residual noise and speech distortion in strong noise. [ABSTRACT FROM AUTHOR]

Abstract The global spread of English as the world lingua franca has an impact on the goals of teaching pronunciation, where 'comfortable intelligibility' should be the goal rather than native-like pronunciation. Jenkins (2000) proposed the Lingua Franca Core (LFC), a syllabus that includes a list of phonological features that are, arguably, the minimum required to result in intelligible communication among non-native speakers of English (NNSs). This study has rethought the contents of this list for Arab learners. To this end, the intelligibility of 50 L1 Arabic learners of English at post-secondary level was evaluated by 18 non-Arab speakers using the buzzer technique, and an index has been developed for unintelligible utterances in the speakers' speech samples. The findings support most of the core features in the LFC except for the quality of the long vowel /ɜː/, rhotic /r/, and word stress in words of more than two syllables. These findings are used to propose a revised version of the LFC syllabus for Arab learners. [ABSTRACT FROM AUTHOR]

Abstract This study investigated the relation between the intelligibility of conversational and clear speech produced by older and younger adults and (a) the acoustic profile of their speech (b) communication effectiveness. Speech samples from 30 talkers from the elderLUCID corpus were used: 10 young adults (YA), 10 older adults with normal hearing (OANH) and 10 older adults with presbycusis (OAHL). Samples were extracted from recordings made while participants completed a problem-solving cooperative task (diapix) with a conversational partner who could either hear them easily (NORM) or via a simulated hearing loss (HLS), which led talkers to naturally adopt a clear speaking style. In speech-in-noise listening experiments involving 21 young adult listeners, speech samples by OANH and OAHL were rated and perceived as less intelligible than those of YA talkers. HLS samples were more intelligible than NORM samples, with greater improvements in intelligibility across conditions seen for OA speech. The presence of presbycusis affected (a) the clear speech strategies adopted by OAHL talkers and (b) task effectiveness: OAHL talkers showed some adaptations consistent with an increase in vocal effort, and it took them significantly longer than the YA group to complete the diapix task. The relative energy in the 1–3 kHz frequency region of the long-term average spectrum was the feature that best predicted: (a) the intelligibility of speech samples, and (b) task transaction time in the HLS condition. Overall, our study suggests that spontaneous speech produced by older adults is less intelligible in babble noise, probably due to less energy present in the 1–3 kHz frequency range rich in acoustic cues. Even mild presbycusis in 'healthy aged' adults can affect the dynamic adaptations in speech that are beneficial for effective communication. Highlights • Spontaneous speech by older adults is less intelligible than young adult speech. • Presbycusis affected clear speech strategies and task effectiveness. • ME1-3 kHz measure best predicted speech intelligibility and task effectiveness. [ABSTRACT FROM AUTHOR]

With the development of information and communications technology, conferences and remote education using teleconference systems have become common. When a teleconference system is used, the sound heard in a receiving room includes the acoustic characteristics of both the utterance and receiving rooms, in addition to the characteristics of the transmission via the teleconference system and Internet. Even today, when the digital technology is widely used, quality problems related to sound transmission remain; in particular, the influence of the reverberation of the conference room causes deterioration of the sound quality. Studies aiming to improve the quality of the signal transmission have been conducted; however, there are no acoustic countermeasure methods considering the acoustic characteristics of the two rooms connected by a teleconference system and performing the sound quality evaluation. In this study, focusing on a teleconference system sharing video and audio between two separate rooms, we evaluated the improvement in the sound transmission performance due to the addition of sound absorption to the conference room by examining the correspondence between the subjective assessment results and acoustical physical indexes. Additionally, the acoustical physical indexes that allow evaluating the quality of the sound transmitted via the teleconference system were also examined by comparing with the result of a subjective assessment. Intelligibility tests were conducted, listening difficulty ratings were evaluated, and the impulse response, STI, Clarity (C 50 ), and reverberation time were measured in an actual teleconference system. We observed that, before the addition of sound absorption, the sound was difficult to listen to due to the acoustic characteristics of both of the utterance and receiving rooms. However, by suppressing reverberation in both the utterance and receiving rooms by using sound-absorbing panels, the difficulties in listening was improved. By examination of the correspondence between the subjective assessment results and acoustical physical indexes, we proved that STI and Clarity (C 50 ) are highly correlated with intelligibility. On the other hand, reverberation time was found to be uncorrelated with the intelligibility of the rooms of teleconference systems. [ABSTRACT FROM AUTHOR]

We examined the frequency specificity of amplitude envelope patterns in 4 frequency bands, which universally appeared through factor analyses applied to power fluctuations of critical-band filtered speech sounds in 8 different languages/dialects [Ueda and Nakajima (2017). Sci. Rep., 7 (42468)]. A series of 3 perceptual experiments with noise-vocoded speech of Japanese sentences was conducted. Nearly perfect (92–94%) mora recognition was achieved, without any extensive training, in a control condition in which 4-band noise-vocoded speech was employed (Experiments 1–3). Blending amplitude envelope patterns of the frequency bands, which resulted in reducing the number of amplitude envelope patterns while keeping the average spectral levels unchanged, revealed a clear deteriorating effect on intelligibility (Experiment 1). Exchanging amplitude envelope patterns brought generally detrimental effects on intelligibility, especially when involving the 2 lowest bands ( ≲ 1850 Hz; Experiment 2). Exchanging spectral levels averaged in time had a small but significant deteriorating effect on intelligibility in a few conditions (Experiment 3). Frequency specificity in low-frequency-band envelope patterns thus turned out to be conspicuous in speech perception. [ABSTRACT FROM AUTHOR]

When producing speech in noisy backgrounds talkers reflexively adapt their speaking style in ways that increase speech-in-noise intelligibility. This adaptation, known as the Lombard effect, is likely to have an adverse effect on the performance of automatic speech recognition systems that have not been designed to anticipate it. However, previous studies of this impact have used very small amounts of data and recognition systems that lack modern adaptation strategies. This paper aims to rectify this by using a new audio-visual Lombard corpus containing speech from 54 different speakers – significantly larger than any previously available – and modern state-of-the-art speech recognition techniques. The paper is organised as three speech-in-noise recognition studies. The first examines the case in which a system is presented with Lombard speech having been exclusively trained on normal speech. It was found that the Lombard mismatch caused a significant decrease in performance even if the level of the Lombard speech was normalised to match the level of normal speech. However, the size of the mismatch was highly speaker-dependent thus explaining conflicting results presented in previous smaller studies. The second study compares systems trained in matched conditions (i.e., training and testing with the same speaking style). Here the Lombard speech affords a large increase in recognition performance. Part of this is due to the greater energy leading to a reduction in noise masking, but performance improvements persist even after the effect of signal-to-noise level difference is compensated. An analysis across speakers shows that the Lombard speech energy is spectro-temporally distributed in a way that reduces energetic masking, and this reduction in masking is associated with an increase in recognition performance. The final study repeats the first two using a recognition system training on visual speech. In the visual domain, performance differences are not confounded by differences in noise masking. It was found that in matched-conditions Lombard speech supports better recognition performance than normal speech. The benefit was consistently present across all speakers but to a varying degree. Surprisingly, the Lombard benefit was observed to a small degree even when training on mismatched non-Lombard visual speech, i.e., the increased clarity of the Lombard speech outweighed the impact of the mismatch. The paper presents two generally applicable conclusions: i) systems that are designed to operate in noise will benefit from being trained on well-matched Lombard speech data, ii) the results of speech recognition evaluations that employ artificial speech and noise mixing need to be treated with caution: they are overly-optimistic to the extent that they ignore a significant source of mismatch but at the same time overly-pessimistic in that they do not anticipate the potential increased intelligibility of the Lombard speaking style. [ABSTRACT FROM AUTHOR]

Purpose Perceived listening effort is a perceptual dimension used to identify the amount of work necessary to understand disordered speech. The purpose of this study was to investigate the utility of perceived listening effort to provide unique information about disordered speech. The relationships between perceived listening effort and two current outcome measures (speech acceptability, intelligibility) were examined for listeners rating electrolaryngeal speech, along with their reliability and intra-rater agreement. Methods Ten healthy male speakers read low-context sentences using an electrolarynx. Twenty-five inexperienced listeners orthographically transcribed and rated the stimuli for perceived listening effort and speech acceptability using a visual analog scale. Strict reliability and agreement criteria were set. Results Perceived listening effort was moderately to strongly correlated with intelligibility ( r  = −0.76) and acceptability ( r  = −0.80), each of which contributed uniquely to ratings of perceived listening effort. However, only 17 listeners met stringent reliability and agreement criteria. Conclusions Ratings of perceived listening effort may provide unique information about the communicative success of individuals with communication disorders. There is great variability, however, among inexperienced listeners’ perceptual ratings of electrolaryngeal speech. Future research should investigate variables that may affect perceived listening effort specifically and auditory-perceptual ratings in general. [ABSTRACT FROM AUTHOR]

The information we obtain from how speakers sound—for example their accent—affects how we interpret the messages they convey. A clear example is foreign accented speech, where reduced intelligibility and speaker's social categorization (out-group member) affect memory and the credibility of the message (e.g., less trustworthiness). In the present study, we go one step further and ask whether evaluations of messages are also affected by regional accents—accents from a different region than the listener. In the current study, we report results from three experiments on immediate memory recognition and immediate credibility assessments as well as the illusory truth effect. These revealed no differences between messages conveyed in local—from the same region as the participant—and regional accents—from native speakers of a different country than the participants. Our results suggest that when the accent of a speaker has high intelligibility, social categorization by accent does not seem to negatively affect how we treat the speakers' messages. [ABSTRACT FROM AUTHOR]

• Focus on authentic and spontaneous speech produced outside the laboratory. • Importance of acquiring and consolidating multidialectal listening skills. • The strength of a speaker's accent significantly affected comprehensibility ratings. • Intelligibility was not always divided along Inner and non-Inner Circle boundaries. • No correlation between comprehensibility and intelligibility was detected. This study investigates how well English as a Foreign Language (EFL) learners report understanding (i.e. comprehensibility) and actually understand (i.e. intelligibility) native and non-native accents of English, and how EFL learners' self-reported ease of understanding and actual understanding of these accents are aligned. Thirty-three Dutch-speaking EFL learners performed a comprehensibility and accentedness judgement task, followed by an orthographic transcription task. The judgement task elicited listeners' scalar ratings of authentic speech from eight speakers with traditional Inner, Outer and Expanding Circle accents. The transcription task assessed listeners' actual understanding of 40 sentences produced by the same eight speakers. Speakers with Inner Circle accents were reported to be more comprehensible than speakers with non-Inner Circle accents, with Expanding Circle speakers being easier to understand than Outer Circle speakers. The strength of a speaker's accent significantly affected listeners' comprehensibility ratings. Most speakers were highly intelligible, with transcription accuracy ranging between 79% and 95%. Listeners' self-reported ease of understanding the speakers in our study generally matched their actual understanding of those speakers, but no correlation between comprehensibility and intelligibility was detected. The study foregrounds the effect of native and non-native accents on comprehensibility and intelligibility, and highlights the importance of multidialectal listening skills. [ABSTRACT FROM AUTHOR]

Intelligibility research has substantially advanced our understanding of how second-language (L2) English intelligibility is influenced by characteristics of the L2 speaker's pronunciation and experience and by listener-related variables. Comparatively few studies, however, have investigated the influence of contextual factors on intelligibility. This study aims to address this lack with an analysis of how one Thai learner of L2 English increasingly utilized context for constructing L2 English intelligibility in interactions. The focal participant was a Thai college student attending an eight-week business English course at a Thai university. The data for this study came from a series of one-on-one conversations, alternating among six instructors with diverse first language backgrounds and discussions during regular office hours. Applying the methodology of membership categorization analysis (MCA) and conversation analysis (CA), the analysis revealed that the focal participant increasingly used sequential organization and descriptors in order to proactively construct an intelligible pronunciation of the job referent term that she used. The findings add to our understanding of how context supports the interactive construction of L2 English intelligibility. They also support the use of (M)CA as an innovative methodology for intelligibility research and, further, suggest teaching implications for ensuring L2 English intelligibility in interaction. [ABSTRACT FROM AUTHOR]

This qualitative study critically examines the intelligibility of the teacher talk of novice native speaker English language teachers. It focuses on difficulties teachers face in adjusting their own English so that their learners can understand them. The paper uses two data sources: learners’ perceptions of recorded teacher talk and analysis of the teacher talk itself. For the teacher talk analysis, the study develops an integrated framework based on key concepts from Systemic Functional Linguistics (SFL). This analysis showed the complex interplay between different levels of meaning, as well as the roles played by both the immediate situational context and the broader cultural context. In particular, the analysis illustrated the crucial roles that both textual meaning (e.g. coherence and cohesion) and context play in the intelligibility of teacher talk. The broader implications of the study for research and teaching relating to intercultural discourse both inside and outside the classroom are discussed. [ABSTRACT FROM AUTHOR]

Many international students at U.S. universities study in intensive English courses to improve their language skills before taking content-oriented courses toward their degrees. English for Academic Purposes (EAP) instructors in intensive courses and university faculty in content courses both listen to international student speech, but it is unclear whether they perceive it similarly or differently. In the present study, two groups (Content Faculty and EAP Instructors) provided comprehensibility ratings and transcribed an excerpt of speech from international students. Both groups of participants answered questions about their experience with the English of international students and other non-native speakers and their attitudes towards the English proficiency of international students. Comprehensibility ratings and intelligibility scores for both groups were similar, but EAP Instructors were able to transcribe more accurately for less-intelligible speakers. Content Faculty with negative attitudes towards international students' language abilities gave lower comprehensibility ratings than those with positive attitudes, even though their transcription accuracy was equivalent. These results strengthen our understanding of the relationship between comprehensibility and intelligibility and have implications for university EAP curricula. [ABSTRACT FROM AUTHOR]

Bone conduction and in-ear microphones pick up the Bone-conducted (BC) speech, which has traveled through bones and soft tissues. This BC speech is less sensitive to surrounding noise than Air-conducted (AC) speech. Therefore, there is an interest in recording this signal. However, the intelligibility and quality of these microphones are known to be a limit to their use. Previous work has noted confusion between vowel sounds in terms of intelligibility. To evaluate the quality and intelligibility, studies rely on subjective and objective tests. This paper aims to determine if the standard objective methods for rating speech quality and intelligibility can be applied to BC speech recorded through these microphones. In order to estimate intelligibility, a subjective test based on vowel recognition was compared to STOI and to a new criterion based on second formant frequencies of oral vowels. For speech quality estimation, MUSHRA and PESQ tests were compared. Results show difficulties in using objective methods instead of subjective ones. Therefore, for ongoing studies, it is suggested to use subjective methods to evaluate speech quality and intelligibility. • Objective and subjective evaluation of speech quality do not correlate. • Introduction of a new objective metric to evaluate vowel recognition. • The new objective metric for vowel recognition works only for in-ear microphones. • Objective and subjective evaluation of intelligibility do not correlate. [ABSTRACT FROM AUTHOR]

• Nonnative comprehension advantage for nonnative listeners over native listeners. • Nonnative comprehension advantage for nonnative speech over native speech. • Gradience in ISIB-L and -T effects modulated by speaker and listener proficiency. • Benefit for common- over unique-phoneme words for strongly accented speech. Previous research on the Interlanguage Speech Intelligibility Benefit (ISIB) indicates nonnative listeners may have an advantage at understanding nonnative speech of talkers with the same first language (L1) due to shared interlanguage knowledge. The present study offers a comprehensive analysis of various factors that may modulate this advantage, including the proficiency of both the listeners and the talkers, the mapping of phonemes between the L1 and second language (L2), and the acoustic properties of the phones. Accuracy scores on a lexical decision task were used to investigate both native English listeners' and native Mandarin learners' of English perception of native English and Mandarin-accented English speech. Results show clear ISIB-L and ISIB-T effects and demonstrate the dynamic nature of ISIB effects, with both being modulated by speaker and listener proficiency. More striking ISIB effects typically occur at the most extreme ends of accentedness. Additionally, an advantage for common-phoneme over unique-phoneme words in nonnative speech was observed. While nonnative productions of common-phoneme words are more accurate than those of unique-phoneme words, for the most accented productions, nonnative listeners are faster to respond to these unique, often mispronounced, productions. The nonnative listener advantage at perceiving nonnative speech depends on various factors, including listener proficiency, speaker proficiency, phoneme characteristics, and the acoustics of specific speech tokens. [ABSTRACT FROM AUTHOR]

Although several studies have investigated neural oscillations in response to acoustically degraded speech, it is still a matter of debate which neural frequencies reflect speech intelligibility. Part of the problem is that effects of acoustics and intelligibility have so far not been considered independently. In the current electroencephalography (EEG) study the amount of acoustic periodicity (i.e. the amount of time the stimulus sentences were voiced) was manipulated, while using the listeners’ spoken responses to control for differences in intelligibility. Firstly, the total EEG power changes in response to completely aperiodic (noise-vocoded) speech and speech with a natural mix of periodicity and aperiodicity were almost identical, while an increase in theta power (5–6.3 Hz) and a trend for less beta power (11–18 Hz) were observed in response to completely periodic speech. These two effects are taken to indicate an information processing conflict caused by the unnatural acoustic properties of the stimuli, and that the subjects may have internally rehearsed the sentences as a result of this. Secondly, we separately investigated effects of intelligibility by sorting the trials in the periodic condition according to the listeners’ spoken responses. The comparison of intelligible and largely unintelligible trials revealed that the total EEG power in the delta band (1.7–2.7 Hz) was markedly increased during the second half of the intelligible trials, which suggests that delta oscillations are an indicator of successful speech understanding. [ABSTRACT FROM AUTHOR]

Time-reversed speech has been known to effectively mask information for speech privacy applications. However, the annoyance and distraction caused by the time-reversed speech-like masking sound is higher than other masking sound. This study investigates the effects of adding artificial reverberation to the time-reversed speech. Subjective listening tests have been conducted to measure the intelligibility of target speech, annoyance and distraction caused by the masking sound. The experimental results suggest that adding artificial reverberation to a speech-like masking sound has a significant effect to reduce the annoyance level while maintaining the masking effectiveness of the original masking sound. A trend was also observed that the addition of artificial reverberation could reduce the level of distraction caused by the masking sound. [ABSTRACT FROM AUTHOR]

This research investigates how deviance in focus marking by means of pitch accent distributions by native and non-native speakers affects native speaker perceptions. It shows that non-native speech is rated as less nativelike, more foreign accented and more difficult to understand than native speech, with speakers’ proficiency as a modulating factor. Even when controlling for segmental deviance, native listeners could distinguish between two utterances that only differed in whether their focus distribution matched their original elicitation context or not, and found the matched utterance more nativelike than the mismatched utterance, based solely on prosodic cues. However, a reaction times experiment reveals that this preference did not influence the processing time of native Dutch utterances with or without prosodic deviance by native listeners. There was a significant difference between reaction times for non-native and native stimuli, but this is most likely due to the slower speech rate of non-native speech. [ABSTRACT FROM AUTHOR]

It has consistently been shown that among the three mainland Scandinavian languages, Danish is most difficult to understand for fellow Scandinavians. Recent research suggests that Danish is spoken significantly faster than Norwegian and Swedish. This finding might partly explain the asymmetric intelligibility among Scandinavian languages. However, since fast speech goes hand in hand with a high amount of speech reduction, the question arises whether the high speech rate as such impairs intelligibility, or the high amount of reduction. In this paper we tear apart these two factors by auditorily presenting 168 Norwegian- and Swedish-speaking participants with 50 monotonised nonsense sentences in four conditions (quick and unclear, slow and clear, quick and clear, slow and unclear) in a translation task. Our results suggest that speech rate has a larger impact on the intelligibility of monotonised speech than naturally occurring reduction. [ABSTRACT FROM AUTHOR]

Objectives: Assessment of long-term objective and subjective voice, speech, articulation, and quality of life in patients with head and neck cancer (HNC) treated with concurrent chemoradiotherapy (CRT) for advanced, stage IV disease.Materials and Methods: Twenty-two disease-free survivors, treated with cisplatin-based CRT for inoperable HNC (1999-2004), were evaluated at 10-years post-treatment. A standard Dutch text was recorded. Perceptual analysis of voice, speech, and articulation was conducted by two expert listeners (SLPs). Also an experimental expert system based on automatic speech recognition was used. Patients' perception of voice and speech and related quality of life was assessed with the Voice Handicap Index (VHI) and Speech Handicap Index (SHI) questionnaires.Results: At a median follow-up of 11-years, perceptual evaluation showed abnormal scores in up to 64% of cases, depending on the outcome parameter analyzed. Automatic assessment of voice and speech parameters correlated moderate to strong with perceptual outcome scores. Patient-reported problems with voice (VHI>15) and speech (SHI>6) in daily life were present in 68% and 77% of patients, respectively. Patients treated with IMRT showed significantly less impairment compared to those treated with conventional radiotherapy.Conclusion: More than 10-years after organ-preservation treatment, voice and speech problems are common in this patient cohort, as assessed with perceptual evaluation, automatic speech recognition, and with validated structured questionnaires. There were fewer complaints in patients treated with IMRT than with conventional radiotherapy. [ABSTRACT FROM AUTHOR]

• Automatic landmark detection by using energy derivatives. • Automatic landmark detection by speech mark toolbox. • Manual landmark detection by praat software. • Comparing these three landmark detection methods. Dysarthria is a disease of motor speech that affects millions of individuals. This impairment induces wrongly pronounced phonemes, variable speech amplitude, low articulation, etc resulting in poor intelligibility. Significant time instants known as landmarks are detected for modifications in the distorted dysarthric speech. The difficulty in accurately locating the regions for modification in an automated fashion is one of the most predominant challenges. Hence it is important to detect the landmarks accurately and modifications have to be carried out for the segment of interest based on estimates. This work aims at identifying the stop consonants in dysarthric speech accurately, in particular, closure onset and burst onset landmarks for stops and, also comparing landmark detection by automatic and manual procedures to improve the intelligibility of dysarthric speech. Automatic landmark detection by using energy derivatives gives more accurate landmark detection than Manual landmark detection. Praat software and Speechmark toolbox are used to detect landmarks. [ABSTRACT FROM AUTHOR]

• Six types of background noise were used as maskers: Pink, Babble, Time-reversed speech with randomly re-ordered frames (T-rev), T-rev with artificial reverberation (Trev + Reverb), Time-reversed speech using overlap-and-add (OLaW), and OLaW with artificial reverberation (OLaW + Reverb). • Some maskers showed clear differences in their effectiveness of masking speech towards native and non-native listeners. • Within the non-native listeners, higher proficiency did not result in lower masking effects in masked speech. • Maskers generated using randomly re-ordered frames (T-rev and T-rev + Reverb) had higher masking effects but were also rated as more annoying. • Considering the balance of tradeoff between intelligibility and annoyance, OLaW and OLaW + Reverb maskers appear to be the most effective maskers for both native and nonnative listeners out of the six maskers. Speech masking is a technique used for protecting speech confidentiality, which is realised by adding maskers to cover target speech. Numerous studies have demonstrated the native and non-native differences in perceiving masked speech, but few have compared the effect of masker types from the perspective of effectiveness of speech privacy and their annoyance levels. This paper reports on the result of an English word perception task by native and non-native listeners where six types of maskers, both speech-like and non-speech-like, are implemented, as well as the annoyance levels of each masker. Natives, non-natives residing in an English-speaking country, and non-natives residing in a non-English-speaking country were tasked to write down sentences when masking sound was present, and also to rate the annoyance levels of the maskers. Results showed that language background significantly affected the performance of unmasked speech, the difference between the two non-native listeners became minimal in the presence of maskers, and maskers annoyed the listener groups differently, calling for a discussion in the selection of a universally effective masker to increase speech privacy. [ABSTRACT FROM AUTHOR]

The sensitivity of intelligibility to ambient noise modulation is analyzed in this paper by means of two laboratory tests. The first one consists of measuring release from masking using acoustic samples composed of speech noise synthesized in the laboratory, but also real signals measured in two open plan offices. The Speech Reception Threshold values obtained from the experiment for the synthetic signals are compared with the literature. Those obtained for the real samples show significant differences as a function of the open-plane office. Secondly, a new indicator based on the calculation of the speech transmission index (IEC 60268-16, 2011) is proposed, by taking into account the modulation of the ambient noise in the 4 Hz octave band. Simultaneously, a second intelligibility experiment is performed, resulting in a very good correlation between the intelligibility scores and the new indicator. To complete the evaluation, the sound samples of the first test are reused to demonstrate that the indicator is a good descriptor of release from masking due to the modulation of ambient noise for the synthetic signals and that it is capable of classifying work spaces in terms of level of distraction. [ABSTRACT FROM AUTHOR]

Purpose Most studies on treatment of prosody in individuals with dysarthria due to Parkinson's disease are based on intensive treatment of loudness. The present study investigates the effect of intensive treatment of speech rate and intonation on the intelligibility of individuals with dysarthria due to Parkinson's disease. Methods A one group pretest–posttest design was used to compare intelligibility, speech rate, and intonation before and after treatment. Participants included eleven Dutch-speaking individuals with predominantly moderate dysarthria due to Parkinson's disease, who received five one-hour treatment sessions per week during three weeks. Treatment focused on lowering speech rate and magnifying the phrase final intonation contrast between statements and questions. Intelligibility was perceptually assessed using a standardized sentence intelligibility test. Speech rate was automatically assessed during the sentence intelligibility test as well as during a passage reading task and a storytelling task. Intonation was perceptually assessed using a sentence reading task and a sentence repetition task, and also acoustically analyzed in terms of maximum fundamental frequency. Results After treatment, there was a significant improvement of sentence intelligibility (effect size .83), a significant increase of pause frequency during the passage reading task, a significant improvement of correct listener identification of statements and questions, and a significant increase of the maximum fundamental frequency in the final syllable of questions during both intonation tasks. Conclusion The findings suggest that participants were more intelligible and more able to manipulate pause frequency and statement-question intonation after treatment. However, the relationship between the change in intelligibility on the one hand and the changes in speech rate and intonation on the other hand is not yet fully understood. Results are nuanced in the light of the operated research design. Learning outcomes: The reader will be able to: (1) describe the effect of intensive speech rate and intonation treatment on intelligibility of speakers with dysarthria due to PD, (2) describe the effect of intensive speech rate treatment on rate manipulation by speakers with dysarthria due to PD, and (3) describe the effect of intensive intonation treatment on manipulation of the phrase final intonation contrast between statements and questions by speakers with dysarthria due to PD. [ABSTRACT FROM AUTHOR]

In this paper a perceptual subspace speech enhancement method using masking property of human auditory system with variance normalization is presented. The masking property of the human auditory system is used while deciding the gain parameters for the algorithm. Spectral Domain Constrained estimator was employed in determining the filter coefficients and colored noise was handled by replacing the noise variance by Rayleigh quotient. Variance normalization is further done to remove the spikes in the values so as to avoid abrupt increase or decrease in power of the output samples making the output more intelligible. The objective measures SNR Loss and SNR LESC were chosen for performance evaluation based on their efficiency in determining the intelligibility of the output. The results show an improved performance of the proposed method over some of the existing speech enhancement methods in terms of intelligibility. [ABSTRACT FROM AUTHOR]

Acoustic parameters, including background-noise levels, reverberation time and intelligibility, were analyzed in 17 auditoria and multi-purpose conference rooms at the University of Extremadura. The study of intelligibility was performed by measuring the objective parameters and by using speech tests to study the subjective responses of listeners (speech intelligibility). Relationships between objective and subjective intelligibility parameters were studied, and the grouping of the experimental data was considered to reduce variability. It was concluded that the STI value is a good predictor of the intelligibility of rooms. Relationships between STI values with background-noise levels and reverberation time were also studied. Different proposals of recommended reverberation time were analyzed, taking into consideration the STI values of the studied rooms. Improvements in the slopes of the recommended equations were suggested. [ABSTRACT FROM AUTHOR]

The present study investigated how non-linguistic, indexical information about talker identity interacts with contributions to sentence intelligibility by the time-varying amplitude (temporal envelope) and fundamental frequency ( F 0 ). Young normal-hearing adults listened to sentences that preserved the original consonants but replaced the vowels with a single vowel production. This replacement vowel selectively preserved amplitude or F 0 cues of the original vowel, but replaced cues to phonetic identity. Original vowel duration was always preserved. Three experiments investigated indexical contributions by replacing vowels with productions from the same or different talker, or by acoustically morphing the original vowel. These stimulus conditions investigated how vowel suprasegmental and indexical properties interact and contribute to intelligibility independently from phonetic information. Results demonstrated that indexical properties influence the relative contribution of suprasegmental properties to sentence intelligibility. F 0 variations are particularly important in the presence of conflicting indexical information. Temporal envelope modulations significantly improve sentence intelligibility, but are enhanced when either indexical or F 0 cues are available. These findings suggest that F 0 and other indexical cues may facilitate perceptually grouping suprasegmental properties of vowels with the remainder of the sentence. Temporal envelope modulations of vowels may contribute to intelligibility once they are successfully integrated with the preserved signal. [ABSTRACT FROM AUTHOR]

This is a qualitative study of the relationship between consonant deletion, consonant insertion, and the pragmatic strategies that maintain mutual intelligibility in English as a Lingua Franca (hereafter, ELF) interactions among university and exchange students at a Japanese university ( Jenkins, 2000; Matsumoto, 2011; O’Neal, 2015 ). Some ELF research claims that consonant deletion attenuates mutual intelligibility in ELF interactions, especially if the consonant deletion occurs in word-initial and word-medial consonant clusters or in consonant clusters in syllable onsets and codas ( Jenkins, 2000, 2007; Deterding, 2013 ). This study assesses the effect of consonant deletion and consonant insertion on the mutual intelligibility of pronunciation in ELF interactions in Japan. Using conversation analytic methodology to examine a corpus of miscommunications among ELF speakers at a Japanese university, within which miscommunications are defined as repair sequences, this study claims that consonant deletion can attenuate mutual intelligibility, and that the insertion of a deleted consonant into a word can help restore mutual intelligibility. Furthermore, this is true regardless of deviance from or approximation to a native speaker pronunciation standard. This study concludes that segmental repair is an effective strategy with which English speakers can maintain mutual intelligibility. [ABSTRACT FROM AUTHOR]

Intelligibility, usually defined as the ability of the listener to recognize words and utterances, is an important consideration for international communication in English. Most research studies have focused on international intelligibility, involving speakers from different language backgrounds. However, there have been few studies of intranational intelligibility, and little is known about how well speakers from ‘the same’ language background understand one another. This study investigated the relationship between accent features and intranational intelligibility by providing 91 listeners in Hong Kong with a range of speech samples taken from Hong Kong media broadcasts in English. These samples contained different combinations of accent features, reflecting different kinds of Hong Kong English accents. Listeners were required to produce orthographic transcripts of the speech samples. Transcript analysis produced a list of words that were frequently mistranscribed, and identification of the accent features involved showed that consonantal modifications were often associated with intelligibility problems. The findings suggest that certain L1-related accent features are capable of reducing intranational intelligibility, as are other accent features and speech processes used by both L1 and L2 English speakers. The study has implications for pronunciation pedagogy, and for those involved with intranational and international communication in English. [ABSTRACT FROM AUTHOR]

A widely-cited study investigating effects of recognition difficulty on the phonetic realization of words ( Wright, 2004 ). Factors of lexical competition in vowel articulation. In J. Local, R. Ogden & R. Temple (Eds.), Papers in laboratory phonology , Vol. VI (pp. 26–50)) reported that vowel dispersion, i.e. distance from the center of the talker's F1/F2 space, was greater in words that represented difficult recognition targets (‘hard’ words) than in easy recognition targets (‘easy’ words). The goal of the current study was to test whether that effect persisted when controlling for known other determinants of F1 and F2. A second goal was to test whether the pattern observed in the recordings analysed in Wright (2004) extended to all monophthongs in the set of recordings of which the words analysed in Wright (2004) formed a subset. We find that the dispersion difference between ‘easy’ and ‘hard’ words vowel dispersion is expected, given previous observations about effects of phonetic environment on vowel formants. When segmental context is taken into account, recognition difficulty fails to be predictive of vowel dispersion, both in the subset and in the larger database. An analysis of the fitted values of models of F1 and F2 based on consonantal factors (but not recognition difficulty) shows that the formant values predicted by those models separate vowels in “easy” and “hard” words in the manner observed in W2004. We discuss the implications for the effect of phonological neighbourhood density on language production, and for the relationship between lexical retrieval, auditory recognition difficulty and pronunciation variation. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study is to document the longitudinal progress of speech intelligibility, speech acceptability, voice, resonance, articulation and oromyofunctional behavior in a male facial transplant patient 8 days, 15 days, 5 months, 12 months and, finally, 21 months after surgery. Method Identical objective (Dysphonia Severity Index, nasometry, acoustic analysis) and subjective (consensus perceptual evaluation, Dutch speech intelligibility test; flexible videolaryngostroboscopy/naso-endoscopy) assessment techniques and questionnaires (speech and voice handicap index, oral health impact profile, facial disability index) were used during each of the five postsurgical assessments. Results The pattern of results shows a longitudinal progress of speech intelligibility and acceptability and of the interactive processes underpinning overall speech intelligibility. Vocal quality is normal and resonance is characterized by hypernasality. The phonetic inventory is complete but four phonetic disorders remain. Outcomes pertaining to articulation (formant analysis) show evident progress over time. Lip functions are improving but still decreased. Conclusions Transplantation of the face in this patient has largely restored speech. To what extent resonance, articulation, and lip functions can be enhanced by the permanent use of a palatal obturator, by specialized facial and lip movement exercises in combination with motor-oriented speech therapy, is subject for further research. Learning outcomes Facial transplantation : Readers will be able to (1) describe the relationship between facial transplantation and the impact on speech and oromyofunctional behavior, (2) identify variables that influence the outcome after facial transplantation, (3) define an assessment protocol after facial transplantation, (4) define facial transplantation. [ABSTRACT FROM AUTHOR]

Acoustic-perceptual characteristics of a faster-than-habitual rate (Fast condition) were examined for speakers with Parkinson's disease (PD) and multiple sclerosis (MS). Judgments of intelligibility for sentences produced at a habitual rate (Habitual condition) and at a faster-than-habitual rate (Fast condition) by 46 speakers with PD or MS as well as a group of 32 healthy speakers revealed that the Fast condition was, on average, associated with decreased intelligibility. However, some speakers’ intelligibility did not decline. To further understand the acoustic characteristics of varied intelligibility in the Fast condition for speakers with dysarthria, a subgroup of speakers with PD or MS whose intelligibility did not decline in the Fast condition ( no decline group, n = 8) and a subgroup of speakers with significantly declined intelligibility ( decline group, n = 8) were compared. Acoustic measures of global speech timing, suprasegmental characteristics, and utterance-level segmental characteristics for vocalics were examined for the two subgroups. Results suggest acoustic contributions to intelligibility under rate modulation are complex. Potential clinical relevance and implications for the acoustic bases of intelligibility are discussed. Learning outcomes: Readers will be able to (1) discuss existing evidence for the use of rate change to facilitate intelligibility, (2) describe acoustic-perceptual characteristics of a faster-than-habitual rate among speakers with mild dysarthria, (3) discuss the relationships between rate, intelligibility, suprasegmental variables, and segmental variables, (4) identify the need to further investigate the acoustic basis for intelligibility and its potential theoretical and clinical implications. [ABSTRACT FROM AUTHOR]

This study compared changes in speech clarity as a function of speaking context. It is well documented that words produced in sentence contexts yield higher intelligibility than words in isolation for speakers with mild to moderate dysarthria. To tease apart the effect of speaker and listener variables, the current study aimed to quantify differences in word intelligibility by speaking task. Eighteen speakers with dysarthria produced a set of 25 words in isolation and within the context of a sentence. Eighteen listeners heard a randomized sample of the isolated productions, single words extracted from the sentences, and the full unaltered sentences. Listeners transcribed what they heard and rated their confidence. Words produced in isolation were just as intelligible as words produced in sentence context, both of which were more intelligible than extracted words. In other words, speakers reduced articulatory clarity in sentence production compared to isolated productions; listeners were able to cope with this reduction in clarity when they had access to contextual information but not when these cues were removed in the extracted condition. These findings are consistent with Lindblom's hypo–hyperarticulation theory in that adults with dysarthria appear to be modulating articulatory precision based on listener/task variables. This work has implications for clinical practice in that isolated word and sentence production tasks yielded equivalent intelligibility findings. Learning outcomes: Readers will recognize that speech intelligibility is influenced by speaker and listener variables and thus the choice of speaking and listening task may yield different results. Commonly held clinical belief is that sentence production tasks yield inflated intelligibility scores but we did not find that in this sample. Findings also indicate that speakers with dysarthria may modulate articulatory clarity in response to listener needs which should be considered in treatment planning. [ABSTRACT FROM AUTHOR]

This study evaluated construct-related validity of the Test of Children ' s Speech ( TOCS ). Intelligibility scores obtained using open-set word identification tasks (orthographic transcription) for the TOCS word and sentence tests and rate scores for the TOCS sentence test (words per minute or WPM and intelligible words per minute or IWPM) were compared for a group of 15 adults (18–30 years of age) with normal speech production and three groups of children: 48 3–6 year-olds with typical speech development and neurological histories (TDS), 48 3–6 year-olds with a speech sound disorder of unknown origin and no identified neurological impairment (SSD-UNK), and 22 3–10 year-olds with dysarthria and cerebral palsy (DYS). As expected, mean intelligibility scores and rates increased with age in the TDS group. However, word test intelligibility, WPM and IWPM scores for the 6 year-olds in the TDS group were significantly lower than those for the adults. The DYS group had significantly lower word and sentence test intelligibility and WPM and IWPM scores than the TDS and SSD-UNK groups. Compared to the TDS group, the SSD-UNK group also had significantly lower intelligibility scores for the word and sentence tests, and significantly lower IWPM, but not WPM scores on the sentence test. The results support the construct-related validity of TOCS as a tool for obtaining intelligibility and rate scores that are sensitive to group differences in 3–6 year-old children, with and without speech sound disorders, and to 3+ year-old children with speech disorders, with and without dysarthria. Learning outcomes Readers will describe the word and sentence intelligibility and speaking rate performance of children with typically developing speech at age levels of 3, 4, 5 and 6 years, as measured by the Test of Children's Speech, and how these compare with adult speakers and two groups of children with speech disorders. They will also recognize what measures on this test differentiate children with speech sound disorders of unknown origin from children with cerebral palsy and dysarthria. [ABSTRACT FROM AUTHOR]

Summary: The following article provides a general review of an area that can be referred to as Forensic Voice. Its goals will be outlined and that discussion will be followed by a description of its major elements. Considered are (1) the processing and analysis of spoken utterances, (2) distorted speech, (3) enhancement of speech intelligibility (re: surveillance and other recordings), (4) transcripts, (5) authentication of recordings, (6) speaker identification, and (7) the detection of deception, intoxication, and emotions in speech. Stress in speech and the psychological stress evaluation systems (that some individuals attempt to use as lie detectors) also will be considered. Points of entry will be suggested for individuals with the kinds of backgrounds possessed by professionals already working in the voice area. [Copyright &y& Elsevier]

• Gammatone filterbank (GTFB) – simple deep neural network (SDNN) based speech enhancement system improves the quality of speech for three different unseen conditions. • The model of GTFB provides finer resolution in low-frequency regions of speech by identifying the speech information from the speech mixture. • The simple DNN model used in this work reduces the structure, the total delay and processing time under different test conditions. • The performance of GTFB-SDNN has shown significant improvement in terms of intelligibility and quality for unseen speaker conditions. Speech signal enhancement achieves high-level performance in recent years using deep learning techniques. However, the deep learning technique in the speech enhancement algorithm degrades the performance of speech, particularly for unseen noises, unseen speakers and moreover, deep learning models are limited to the small number of speakers. Hence, we propose a Gammatone filterbank (GTFB) – simple deep neural network (SDNN) based speech enhancement algorithm to improve the quality of speech for three different unseen conditions. The use of GTFB gives a finer resolution in low-frequency regions of speech, and the SDNN model extracts a noisy GTFB frame as input and maps it to a clean speech GTFB frame. The experimental results are measured objectively using signal-noise-ratio, perceptual evaluation of speech quality, short time objective intelligibility, and subjectively using mean opinion score. The experimental results are carried out using a variety of training and testing models. The performance results show that the proposed GTFB-SDNN are robust to a variety of test situations and outperform existing methods. [ABSTRACT FROM AUTHOR]