Articulation Rate Research Articles

Comparing Measuring Methods for Speech Timing During Rapid Automatic Naming Tasks Using Arabic and English Bilingual Adults

Rapid automatized naming (RAN) tasks have been used to assess word retrieval speed and reading speed. However, measures of reading rate may be affected by structural differences between languages. This study was designed to measure talking speed differences in the utterances of a group of speakers whose first language (L1) was Arabic and second language (L2) was English. Three hypotheses were tested: the language structure differences would result in L2 productions with slower utterance rates; the L2 speaking rate would be characterized by greater utterance interruptions than the L1; and the articulation rate would more accurately indicate the naming speeds of the participants. Twenty Arabic- and English-speaking young adults completed RAN tasks for number and object naming in both languages. Utterance rate, speaking rate, and articulation rate were measured. The participants exhibited similar utterance durations in the two languages and utterance rate in words per second, but faster utterance rates in Arabic when measuring the utterance rate in syllables per second. They exhibited more pauses and longer pauses during the English productions, particularly for the object naming. Finally, the speaking rate in syllables per second and articulation rate in syllables per second were equivalent as utterance rates.

The impact of explicit and implicit instruction on EFL learners’ oral performance

Abstract This quasi-experimental study investigated the impacts of two instructional conditions on the fluency of learners’ performance. In the first condition (strategy training), learners were provided with explicit fluency strategy training for a portion of each lesson before rehearsing versions of the speaking task for the remainder of the lesson. In the second condition (massed practice), learners rehearsed the versions of the target speaking task for the entire lesson. Both instructional conditions allowed learners to benefit from language input and task repetition to help conceptualize and encode the content of their speech. Two intact classes of university EFL learners participated in this study. The data were audio recordings of participants’ oral performance of news report presentations in pre-test and post-test conditions. This data was transcribed and coded for speech rate, articulation rate, phonation/time ratio, number of filled and unfilled pauses, mean duration of pauses, mean length of run, verbatim repetition, and repairs. Although the overall effect of the training was found to be insignificant, the estimation analysis revealed that both instructional conditions improve participants’ speech fluency, with the effect sizes ranging from small to medium. These effect sizes are considered meaningful for the speech fluency development of EFL learners in the study context. Hence, both instructional conditions could be applied as a potentially complementary pedagogical strategy in EFL classrooms at the university level, particularly with regard to increasing the accuracy of teachers’ perceptions of learners’ oral proficiency.

The Impact of Clear and Loud Speech Cues on Acoustic and Perceptual Features of Speech Production in Adolescents With Down Syndrome

Purpose: There are few evidence-based speech interventions designed to alter speech production in a way that ultimately results in increased speech intelligibility in adolescents with Down syndrome (DS). The primary purpose of this study was to examine the impact of clear and loud speech cues on acoustic and perceptual features of speech production in adolescents with DS. Method: Eight adolescents diagnosed with DS repeated sentences of varying lengths in three conditions: habitual, big mouth (i.e., clear speech), and strong voice (i.e., loud speech). Four hundred eighty adult listeners (20 listeners per adolescent per condition) provided orthographic transcriptions of adolescent's speech, which were used to calculate intelligibility scores. Acoustic measures of speech rate, articulation rate, proportion of time spent pausing, vocal intensity, and fundamental frequency were calculated for each sentence. Results: The big mouth condition resulted in significantly increased intelligibility, slowed speech and articulation rates, increased pauses, increased vocal intensity, and increased fundamental frequency. The strong voice condition resulted in significantly increased vocal intensity and fundamental frequency, but no other changes. Speech rate was the only variable that explained any of the variance in intelligibility. Conclusions: Adolescents with DS respond differently to clear and loud speech cues. In particular, clear speech cues resulted in significant increases in intelligibility, but loud speech cues did not. Clear speech cues hold promise as an intervention strategy for adolescents with DS.

A longitudinal investigation of the acoustic properties of infant-directed speech from 6 to 18 months.

Caregivers often modulate their speech when interacting with infants, adapting a register that has been suggested to have attentional, affective and didactic purposes. The present preregistered study examined the longitudinal trajectories of a diverse range of acoustic features of infant-directed speech (IDS) and compared these with adult-directed speech (ADS), in Norwegian parents of 6- to 18-month-old infants. Sixty-nine families participated. Throughout five laboratory visits across one year, parents were recorded reading a picture-book to their infant (IDS) and an experimenter (ADS). The book was designed to tightly control for the linguistic content and context of speech between participants, timepoints and registers. Analyses of a total of 54 594 vowels and 22 958 phrases revealed, first, an overall effect of register: parents used higher pitch, wider pitch range, slower articulation rate, longer vowel duration and more variable and less distinct vowels in IDS than in ADS. Second, significant register-by-age interactions indicated that parents' IDS, compared with their ADS, featured wider pitch range, larger vowel space and shorter vowel duration in older as compared with younger infants, while pitch, articulation rate and vowel variability and distinctiveness remained relatively stable with age. Results are discussed in the context of the proposed functions of IDS.

A Preliminary Investigation of Within-Word Silent Intervals Produced by Children With and Without Neurodevelopmental Disorders.

The categorization of silent intervals during speech production is necessary for accurate measurement of articulation rate and pauses. The primary purpose of this preliminary study was to examine the within-word silent interval associated with the stop closure in word-final stop consonants produced by children with and without neurodevelopmental disorders. Seven children diagnosed with either cerebral palsy or Down syndrome (i.e., children with neurodevelopmental disorders) and eight typically developing children produced a reading passage. Participants were between the ages of 11 and 16 years. Fifty-eight words from the reading passage were identified as having word-final stop consonants. The closure duration of the word-final stop consonant was calculated, both in absolute duration and percent pause time. The articulation rate of the entire passage was calculated. The number of closure durations that met or exceeded the minimum duration threshold to be considered a pause (150 ms) was examined descriptively. Children with neurodevelopmental disorders produced significantly longer closure durations and significantly slower articulation rates than typically developing children. Children with neurodevelopmental disorders produced closure durations that met or exceeded the minimum duration threshold of a pause, but typically developing children, generally, did not. These data indicate the need to examine the location of silent intervals that meet the minimum duration threshold of a pause and correct for articulatory events during the measurement of articulation rate and pauses in children with neurodevelopmental disorders.

Unravelling the relationship between language anxiety and foreign language speech fluency in a monologue production

ABSTRACT This study investigated the interplay between language anxiety of advanced foreign language learners and their speech fluency measured with temporal indices. Language anxiety levels of 59 university level students of English were identified with the Input, Processing and Output Anxiety Scale (the IPOAS; MacIntyre & Gardner, 1994. The effects of induced anxiety on three stages of cognitive processing in computerized vocabulary learning.’ Studies in Second Language Acquisition 16 (1): 1–17. doi:10.1017/S0272263100012560) and the Post-Session Survey on Anxiety. The former informed about the levels of anxiety experienced at three stages of linguistic processing, hence, input anxiety, internal processing anxiety, and output anxiety. The latter was applied to identify language anxiety levels exhibited during a monologue production, reported as task-specific language anxiety. Speech samples from the performance were analyzed for fluency breakdown (the number of filled and silent pauses), speed of speech (articulation rate), and composite measures (speech rate). The findings revealed that the advanced foreign language learners with higher levels of internal processing anxiety and output anxiety used filled pauses more frequently. Furthermore, the levels of output anxiety and task-specific language anxiety were inversely related to speech and articulation rate. The study also showed statistically significant differences in the production of filled pauses and speech rate between advanced foreign language learners with low and high levels of language anxiety as measured by the IPOAS.

The Contributions of the Cerebellar Peduncles and the Frontal Aslant Tract in Mediating Speech Fluency.

Fluent speech production is a complex task that spans multiple processes, from conceptual framing and lexical access, through phonological encoding, to articulatory control. For the most part, imaging studies portraying the neural correlates of speech fluency tend to examine clinical populations sustaining speech impairments and focus on either lexical access or articulatory control, but not both. Here, we evaluated the contribution of the cerebellar peduncles to speech fluency by measuring the different components of the process in a sample of 45 neurotypical adults. Participants underwent an unstructured interview to assess their natural speaking rate and articulation rate, and completed timed semantic and phonemic fluency tasks to assess their verbal fluency. Diffusion magnetic resonance imaging with probabilistic tractography was used to segment the bilateral cerebellar peduncles (CPs) and frontal aslant tract (FAT), previously associated with speech production in clinical populations. Our results demonstrate distinct patterns of white matter associations with different fluency components. Specifically, verbal fluency is associated with the right superior CP, whereas speaking rate is associated with the right middle CP and bilateral FAT. No association is found with articulation rate in these pathways, in contrast to previous findings in persons who stutter. Our findings support the contribution of the cerebellum to aspects of speech production that go beyond articulatory control, such as lexical access, pragmatic or syntactic generation. Further, we demonstrate that distinct cerebellar pathways dissociate different components of speech fluency in neurotypical speakers.

Estimates of speech efficiency in monolingual and bilingual speakers of English.

Introduction The Speech Efficiency Score (SES) serves as an acoustic metric for assessing fluency in conversational speech within the temporal domain. This study leverages SES to investigate conversational speech efficiency among native speakers of American English (AE) compared to speakers of Mandarin-accented English (MAE). Methods SES, speaking rate, articulation rate, and vocabulary diversity were measured and compared between two groups: native AE speakers and MAE speakers. The study utilized conversational speech samples collected from both groups to analyze these metrics. Results Findings indicate a disparity in speaking rate and articulation rate between the AE and MAE groups, with the AE group exhibiting significantly faster speech. However, no significant differences were observed in SES and vocabulary diversity between the two groups. Conclusion The results are discussed in the context of the interplay between speaking rate, speech fluency, and vocabulary diversity. These findings shed light on the maintenance of speech efficiency among bilingual speakers, suggesting that despite differences in speaking rate and articulation rate, SES and vocabulary diversity remain comparable between native AE speakers and MAE speakers. .

Effect of ‘Be Clear’ Treatment on Intelligibility in Adults with Post-Stroke Dysarthria: Acoustic-Perceptual Consequences

Dysarthria is significantly prevalent in individuals with post-stroke etiology. Behavioral treatment remains the foundation of dysarthria treatment approaches. Clear speech is one recent compensatory treatment approach that has gained traction. The present study aimed to determine whether the ‘Be Clear’ treatment significantly improved speech intelligibility, formant centralization ratio (FCR), slopes of second formant transitions (F2 slope), vowel duration, speaking rates, and articulation rates in adults with post-stroke dysarthria. Ten Kannada-speaking participants in the age range of 30 to 66 years of age with post-stroke dysarthria were recruited for the present study. ‘Be Clear’ treatment was practiced over the duration of 16 one-hour sessions across 4 weeks. Participants demonstrated statistically significant improvements in word intelligibility and sentence intelligibility, FCR, F2 slope, vowel duration, speaking rates, and articulation rates following ‘Be Clear’ treatment. Future research could include other acoustic and perceptual measures to evaluate the efficacy of this treatment program on a larger sample size.

PaSCoNT - Parallel Speech Corpus of Northern-central Thai for automatic speech recognition

This paper proposed a Parallel Speech Corpus of Northern-central Thai (PaSCoNT). The purpose of this research is not only to understand the different linguistic characteristics between Northern and Central Thai, but also to utilize this corpus for automatic speech recognition. The corpus is composed of speech data from dialogues of daily life among northern Thai people. We designed 2,000 Northern Thai sentences covering all phonemes, in collaboration with linguists specialized in the Northern Thai dialect. The samples in this study are 200 Northern Thai dialect speakers who had been living in Chiang Mai province for more than 18 years. The speech was recorded in both open and closed environments. In the speech recording, each speaker must read 100 pairs of Northern-Central Thai sentences to ensure that the speech data comes from the same speaker. In total, 100 h of speech were recorded: 50 h of Northern Thai and 50 h of Central Thai. Overall, PaSCoNT consists of 907,832 words and 6,279 vocabulary items. Statistical analysis of the PaSCoNT corpus revealed that 49.64 % of words in the lexicon belongs to the Northern Thai dialect, 50.36 % from the Central Thai dialect, and 1,621 vocabulary items appeared in both Northern and Central Thai. Statistical analysis is used to examine the difference in speech tempo, i.e. time per phoneme (TTP), syllable per minute (SPM), between Northern and Central Thai. The results revealed that there were statistically significant differences speech tempo between Central and Northern Thai. The TTP speaking and articulation rate of Central Thai is lower than Northern Thai whereas SPM speaking and articulation rate of Central Thai is higher than Northern Thai. The results also showed that the ASR model training using Northern Thai speech corpus provides the lower WER% when testing using Northern Thai testing speech data and provides the higher WER% when testing using Central Thai Testing speech data and vice versa. However, the ASR model training using the PaSCoNT speech corpus provides the lower WER% for both Northern Thai and Central Thai testing speech data.

A Systematic Review and Bayesian Meta-Analysis of Acoustic Measures of Prosody in Parkinson's Disease.

Linguistic prosody is affected in Parkinson's disease (PD), which implicates the basal ganglia's role in the production of prosody. However, there is no recent systematic synthesis of the available acoustic evidence of prosodic impairment in PD. This study aimed to identify the acoustic features of linguistic prosody that are consistently affected in PD. The authors systematically reviewed articles that reported acoustic features of prosodic production in PD. Articles focused on fundamental frequency (F0) and its variability, intensity and its variability, speech and articulation rate, and pause duration and ratio. From a total of 648 records identified, 36 met criteria for inclusion and exclusion. For each acoustic measurement and task, data from people with PD (PwPD) were compared with those from controls to extract effect sizes. Pooled effect sizes were estimated using robust Bayesian hierarchical regression models. PD was associated with decreased F0 variability and increased pause duration. There was limited evidence of reduced intensity variability and speech rate in PwPD. No evidence was found to suggest that PD affects articulation rate or pause ratio. The primary acoustic parameters of prosody affected by PD are F0 variability and pause duration. The identification of these acoustic parameters has important clinical implications for the selection of PD management strategies. The association of F0 variability and pause duration with PD suggests that the neural circuits controlling these parameters are at least partly shared and might include the basal ganglia. While the current study focused on the phonetic realization of prosodic cues, future studies should examine whether and how PD affects prosody at higher levels of processing. https://doi.org/10.23641/asha.25892923.

Injection Laryngoplasty of Unilateral Vocal Fold Paralysis Evaluated With Pause and Speech Measurements

ObjectiveThe purpose of this study was to examine a number of pause and speech measurements in patients with unilateral vocal fold paralysis, before and after injection laryngoplasty. The non-invasive measurements were selected to investigate and explain the treatment effect on connected speech in these patients. Study designRetrospective study with repeated measurements design. MethodVoice recordings of 24 patients with unilateral vocal fold paralysis from before and after injection laryngoplasty in local anesthesia were analyzed retrospectively with the computer program Praat. Measurements examined were number of pauses, average pause duration, pause ratio (expressing the amount of pausing during a reading aloud task), number of breath groups, average duration of breath groups, articulation rate, speaking rate, maximum phonation time and voice handicap index. ResultsInjection laryngoplasty had a significant improving effect on the number of pauses, pause ratio, number of breath groups, average duration of breath groups, articulation rate, speaking rate, maximum phonation time and voice handicap index. Maximum phonation time before treatment correlated with several pause- and speech measurements. ConclusionThe results showed that treatment with injection laryngoplasty had a clear effect on several pause and speech measurements and that these measurements correlated with maximum phonation time, but not with voice handicap index.

Do clutterers really speak fast?

Objectives: This study aims to determine whether there is a difference between the speech and articulation rates of people with cluttering (PWC) and controls. Patients and Methods: The descriptive study included 11 PWC (4 males, 7 females; mean age: 36±11 years; range, 23 to 52 years) and 11 controls (4 males, 7 females; mean age: 35.5±10.7 years; range, 22 to 50 years) between February 2023 and May 2023. Three hundred syllables of speech samples were recorded and analyzed using two different rates of speech techniques. Normal disfluencies and pauses were included in the measurements of speech rate, but these linguistic elements were excluded from global time in the calculation of articulation rate. The ratios of 300 syllables to time were compared between the PWC and control groups. Results: According to the descriptive results, the standard deviations of the PWC in both rate assessments were higher. A significant difference was found between the two groups in the speech rate (p=0.001) and articulation rate (p<0.001). The PWC talked about 1.5 syllables per second faster than typical speakers. Conclusion: The objective measurements showed that PWC were mostly rapid speakers. Speech rates of PWC should be addressed as a therapy goal, but there is a need for further studies to examine the speech motor characteristics of PWC.

Exploring automatic methods for the construction of multimodal interpreting corpora. How to transcribe linguistic information and identify paralinguistic properties?

AbstractIn corpus-based interpreting studies, typical challenges exist in the time-consuming and labour-intensive nature of transcribing spoken data and in identifying prosodic properties. This paper addresses these challenges by exploring methods for the automatic compilation of multimodal interpreting corpora, with a focus on English/Chinese Consecutive Interpreting. The results show that: 1) automatic transcription can achieve an accuracy rate of 95.3% in transcribing consecutive interpretations; 2) prosodic properties related to filled pauses, unfilled pauses, articulation rate, and mispronounced words can be automatically extracted using our rule-based programming; 3) mispronounced words can be effectively identified by employing Confidence Measure, with any word having a Confidence Measure lower than 0.321 considered as mispronounced; 4) automatic alignment can be achieved through the utilisation of automatic segmentation, sentence embedding, and alignment techniques. This study contributes to interpreting studies by broadening the empirical understanding of orality, enabling multimodal analyses of interpreting products, and providing a new methodological solution for the construction and utilisation of multimodal interpreting corpora. It also has implications in exploring applicability of new technologies in interpreting studies.

The relationship of rate and pause features to the communicative participation of people living with ALS.

Many people living with amyotrophic lateral sclerosis (PALS) report restrictions in their day-to-day communication (communicative participation). However, little is known about which speech features contribute to these restrictions. This study evaluated the effects of common speech symptoms in PALS (reduced overall speaking rate, slowed articulation rate, and increased pausing) on communicative participation restrictions. Participants completed surveys (the Communicative Participation Item Bank-short form; the self-entry version of the ALS Functional Rating Scale-Revised) and recorded themselves reading the Bamboo Passage aloud using a smartphone app. Rate and pause measures were extracted from the recordings. The association of various demographic, clinical, self-reported, and acoustic speech features with communicative participation was evaluated with bivariate correlations. The contribution of salient rate and pause measures to communicative participation was assessed using multiple linear regression. Fifty seven people living with ALS participated in the study (mean age = 61.1 years). Acoustic and self-report measures of speech and bulbar function were moderately to highly associated with communicative participation (Spearman rho coefficients ranged from rs = 0.48 to rs = 0.77). A regression model including participant age, sex, articulation rate, and percent pause time accounted for 57% of the variance of communicative participation ratings. Even though PALS with slowed articulation rate and increased pausing may convey their message clearly, these speech features predict communicative participation restrictions. The identification of quantitative speech features, such as articulation rate and percent pause time, is critical to facilitating early and targeted intervention and for monitoring bulbar decline in ALS.

Do Acoustic Characteristics of Dysarthria in People With Parkinson's Disease Differ Across Languages?

Cross-language studies suggest more similarities than differences in how dysarthria affects the speech of people with Parkinson's disease (PwPD) who speak different languages. In this study, we aimed to identify the relative contribution of acoustic variables to distinguish PwPD from controls who spoke varieties of two Romance languages, French and Portuguese. This bi-national, cross-sectional, and case-controlled study included 129 PwPD and 124 healthy controls who spoke French or Portuguese. All participants underwent the same clinical examinations, voice/speech recordings, and self-assessment questionnaires. PwPD were evaluated off and on optimal medication. Inferential analyses included Disease (controls vs. PwPD) and Language (French vs. Portuguese) as factors, and random decision forest algorithms identified relevant acoustic variables able to distinguish participants: (a) by language (French vs. Portuguese) and (b) by clinical status (PwPD on and off medication vs. controls). French-speaking and Portuguese-speaking individuals were distinguished from each other with over 90% accuracy by five acoustic variables (the mean fundamental frequency and the shimmer of the sustained vowel /a/ production, the oral diadochokinesis performance index, the relative sound level pressure and the relative sound pressure level standard deviation of the text reading). A distinct set of parameters discriminated between controls and PwPD: for men, maximum phonation time and the oral diadochokinesis speech proportion were the most significant variables; for women, variables calculated from the oral diadochokinesis were the most discriminative. Acoustic variables related to phonation and voice quality distinguished between speakers of the two languages. Variables related to pneumophonic coordination and articulation rate were the more effective in distinguishing PwPD from controls. Thus, our research findings support that respiration and diadochokinesis tasks appear to be the most appropriate to pinpoint signs of dysarthria, which are largely homogeneous and language-universal. In contrast, identifying language-specific variables with the speech tasks and acoustic variables studied was less conclusive.

A Methodological Approach to Quantifying Silent Pauses, Speech Rate, and Articulation Rate across Distinct Narrative Tasks: Introducing the Connected Speech Analysis Protocol (CSAP).

The examination of connected speech may serve as a valuable tool for exploring speech output in both healthy speakers and individuals with language disorders. Numerous studies incorporate various fluency and silence measures into their analyses to investigate speech output patterns in different populations, along with the underlying cognitive processes that occur while speaking. However, methodological inconsistencies across existing studies pose challenges in comparing their results. In the current study, we introduce CSAP (Connected Speech Analysis Protocol), which is a specific methodological approach to investigate fluency metrics, such as articulation rate and speech rate, as well as silence measures, including silent pauses' frequency and duration. We emphasize the importance of employing a comprehensive set of measures within a specific methodological framework to better understand speech output patterns. Additionally, we advocate for the use of distinct narrative tasks for a thorough investigation of speech output in different conditions. We provide an example of data on which we implement CSAP to showcase the proposed pipeline. In conclusion, CSAP offers a comprehensive framework for investigating speech output patterns, incorporating fluency metrics and silence measures in distinct narrative tasks, thus allowing a detailed quantification of connected speech in both healthy and clinical populations. We emphasize the significance of adopting a unified methodological approach in connected speech studies, enabling the integration of results for more robust and generalizable conclusions.

What contributes to fluent L2 speech? Examining cognitive and utterance fluency link with underlying L2 collocational processing speed and accuracy

AbstractSecond language (L2) fluency research has suggested that a range of linguistic knowledge and processing speed serve as cognitive fluency (CF) underlying L2 utterance fluency (UF). Building on prior CF-UF link studies, this study explored L2 collocational processing speed and accuracy as underlying CF measures. This study also explored the phrasal frequency effect on the relationship between collocational processing speed and UF to test whether the processing speed of higher-frequency collocations is more strongly related to UF. A total of 108 Japanese university students completed a phrasal acceptability judgment task with adjective–noun collocations pooled from the Academic Collocation List. Speech was elicited in an argumentative speech task, and UF measures were computed based on speed, breakdown, and repair fluency. The results revealed that the collocational processing speed was weakly tied to articulation rate and mid-clause and end-clause silent pause ratio (rho = |.271–.322|), while the collocational processing accuracy was weakly to moderately tied to most UF measures except filled pause ratio (rho = |.281–.368|). The collocation frequency moderated the relationship between the processing speed and UF, suggesting that high-frequency collocations served as a proxy for automaticity in speech production. Implications for CF-UF link research are discussed.

Bilateral Deep Brain Stimulation of the Ventral Intermediate Nucleus of the Thalamus Improves Objective Acoustic Measures of Essential Vocal Tremor.

Deep brain stimulation of the ventral intermediate nucleus of the thalamus (VIM-DBS) is an established treatment for medically refractory essential tremor. However, the effect of VIM-DBS on vocal tremor remains poorly understood, with results varying by method of vocal tremor assessment and stimulation laterality. This single-center study measures the effect of bilateral VIM-DBS on essential vocal tremor using blinded objective acoustic voice analysis. Ten patients with consecutive essential tremor with comorbid vocal tremor receiving bilateral VIM-DBS underwent voice testing before and after implantation of DBS in this prospective cohort study. Objective acoustic measures were extracted from the middle one second of steady-state phonation including cepstral peak prominence, signal-to-noise ratio, percentage voicing, tremor rate, extent of fundamental frequency modulation, and extent of intensity modulation. DBS surgery was performed awake with microelectrode recording and intraoperative testing. Postoperative voice testing was performed after stable programming. Patients included 6 female and 4 male, with a mean age of 67 ± 6.7 years. The VIM was targeted with the following coordinates relative to the mid-anterior commissure:posterior commissure point: 13.2 ± 0.6 mm lateral, 6.2 ± 0.7 mm posterior, and 0.0 mm below. Mean programming parameters were amplitude 1.72.0 ± 0.6 mA, pulse width 63.0 ± 12.7 µs, and rate 130.6 ± 0.0 Hz. VIM-DBS significantly improved tremor rate from 4.43 ± 0.8 Hz to 3.2 ± 0.8 Hz ( P = .001) CI (0.546, 1.895), jitter from 1 ± 0.94 to 0.53 ± 0.219 ( P = .02) CI (-0.124, 1.038), cepstral peak prominence from 13.6 ± 3.9 to 18.8 ± 2.9 ( P = .016) CI (-4.100, -0.235), signal-to-noise ratio from 15.7 ± 3.9 to 18.5 ± 3.7 ( P = .02) CI (-5.598, -0.037), and articulation rate from 0.77 ± 0.2 to 0.82 ± .14 ( P = .04) CI (-0.097, 0.008). There were no major complications in this series. Objective acoustic voice analyses suggest that bilateral VIM-DBS effectively reduces vocal tremor rate and improves voicing. Further studies using objective acoustic analyses and laryngeal imaging may help refine surgical and stimulation techniques and evaluate the effect of laterality on vocal tremor.

Evaluating Speaker-Listener Cognitive Effort in Speech Communication Through Brain-to-Brain Synchrony: A Pilot Functional Near-Infrared Spectroscopy Investigation.

We explore a new approach to the study of cognitive effort involved in listening to speech by measuring the brain activity in a listener in relation to the brain activity in a speaker. We hypothesize that the strength of this brain-to-brain synchrony (coupling) reflects the magnitude of cognitive effort involved in verbal communication and includes both listening effort and speaking effort. We investigate whether interbrain synchrony is greater in native-to-native versus native-to-nonnative communication using functional near-infrared spectroscopy (fNIRS). Two speakers participated, a native speaker of American English and a native speaker of Korean who spoke English as a second language. Each speaker was fitted with the fNIRS cap and told short stories. The native English speaker provided the English narratives, and the Korean speaker provided both the nonnative (accented) English and Korean narratives. In separate sessions, fNIRS data were obtained from seven English monolingual participants ages 20-24 years who listened to each speaker's stories. After listening to each story in native and nonnative English, they retold the content, and their transcripts and audio recordings were analyzed for comprehension and discourse fluency, measured in the number of hesitations and articulation rate. No story retellings were obtained for narratives in Korean (an incomprehensible language for English listeners). Utilizing fNIRS technique termed sequential scanning, we quantified the brain-to-brain synchronization in each speaker-listener dyad. For native-to-native dyads, multiple brain regions associated with various linguistic and executive functions were activated. There was a weaker coupling for native-to-nonnative dyads, and only the brain regions associated with higher order cognitive processes and functions were synchronized. All listeners understood the content of all stories, but they hesitated significantly more when retelling stories told in accented English. The nonnative speaker hesitated significantly more often than the native speaker and had a significantly slower articulation rate. There was no brain-to-brain coupling during listening to Korean, indicating a break in communication when listeners failed to comprehend the speaker. We found that effortful speech processing decreased interbrain synchrony and delayed comprehension processes. The obtained brain-based and behavioral patterns are consistent with our proposal that cognitive effort in verbal communication pertains to both the listener and the speaker and that brain-to-brain synchrony can be an indicator of differences in their cumulative communicative effort. https://doi.org/10.23641/asha.25452142.