Formants F1 Research Articles

An Acoustic–Phonetic Description of Hidatsa Vowels

In this study, we report on results of a preliminary acoustic–phonetic analysis of the Hidatsa vowel system. We conducted acoustic measurements of Hidatsa vowels in terms of averaged temporal and spectral properties of these phones. Our durational analysis provides strong evidence that Hidatsa has a ten-vowel system with phonemically long and short vowels, in addition to two diphthongs. Our spectral measurements consisted of averages and time-evolution dynamic properties of the first three formants (F1, F2 and F3) at 30 equally spaced time points along the central portion of each vowel. The centers and distributions of the F1 and F2 formants, as well as their time-averaged trajectories, provide strong evidence for separate vowel qualities for both the short and long vowels. These measurements also show that all Hidatsa vowels have some degree of time-dependent spectral change, with the back vowels generally displaying a longer time-evolution track. Lastly, our results also indicate that in Hidatsa mid-short vowels do not appear with the same frequency as the other vowels, and that the short [é] has no unstressed counterpart.

Monaural and binaural masking release with speech-like stimuli.

The relevance of comodulation and interaural phase difference for speech perception is still unclear. We used speech-like stimuli to link spectro-temporal properties of formants with masking release. The stimuli comprised a tone and three masker bands centered at formant frequencies F1, F2, and F3 derived from a consonant-vowel. The target was a diotic or dichotic frequency-modulated tone following F2 trajectories. Results showed a small comodulation masking release, while the binaural masking level difference was comparable to previous findings. The data suggest that factors other than comodulation may play a dominant role in grouping frequency components in speech.

The content of reindeer male vocalisations: acoustic cues to age and size

ABSTRACT Some acoustic parameters of animal vocalisations have been shown to reliably indicate male quality and play a role in mate and rival assessment. Reindeer possess a peculiar vocal tract anatomy involving a laryngeal air sac which probably acts as an additional filter, making it a candidate species for novel investigations in the field of bioacoustics. We investigated whether some acoustic parameters of male rutting vocalisations were good indicators of age and body weight (used as an index for body size). We did this by performing acoustic analyses using recordings collected from a semi-domesticated reindeer population in northern Finland. We found the age of subadult males (aged 2.5–4.5 years) to be negatively correlated with formant F3 and formant spacing, suggesting that their vocalisations convey information on the caller’s age. Individual formant frequencies were not affected by male body weight, but formant spacing was lower in heavier males. Despite the presence of the laryngeal air sac, formant spacing seems to be an acoustic parameter influencing mate and rival assessment in reindeer as it gives an honest indication of male body size. We discuss the importance of reliable acoustic cues to quality indices in sexual selection contexts.

Towards multidimensional attentive voice tracking—estimating voice state from auditory glimpses with regression neural networks and Monte Carlo sampling

Selective attention is a crucial ability of the auditory system. Computationally, following an auditory object can be illustrated as tracking its acoustic properties, e.g., pitch, timbre, or location in space. The difficulty is related to the fact that in a complex auditory scene, the information about the tracked object is not available in a clean form. The more cluttered the sound mixture, the more time and frequency regions where the object of interest is masked by other sound sources. How does the auditory system recognize and follow acoustic objects based on this fragmentary information? Numerous studies highlight the crucial role of top-down processing in this task. Having in mind both auditory modeling and signal processing applications, we investigated how computational methods with and without top-down processing deal with increasing sparsity of the auditory features in the task of estimating instantaneous voice states, defined as a combination of three parameters: fundamental frequency F0 and formant frequencies F1 and F2. We found that the benefit from top-down processing grows with increasing sparseness of the auditory data.

Impact of prominence type on the coarticulation of vowels following palatalized consonants

The quantitative impact of prominence (neutral vs emphatic stress) on the coarticulation of the Russian low [æ], mid [e] and high [i] front vowels is evaluated in CV sequences with palatalized consonants of various places of obstruction. The research is conditioned by the aims of speech synthesis and recognition of the Russian language, the current data in the field being insufficient. First order linear equations (locus equations) are used to evaluate the degree of CV coarticulation. The experiment is performed on CjVCjV nonsense words imbedded in the middle position of a carrier phrase «Vyros CVCV sjyljnym» («CjVCjV has grown up strong»). The first syllable of the target words was uttered both with neutral and emphatic stress. The Praat software was used to measure F2 formant values at vowel onsets and central parts. It was established that linear regression slopes are similar both in the Y-intercepts and slope coefficients for the palatalized consonants of various places of obstruction uttered with the same prominence. The degree of coarticulation was different depending upon the type of prominence (neutral or emphatic): the coefficients were lower in case of the emphatic stress compared to those of the neutral one. ANOVA analysis and Student’s t-test were performed to reveal the difference in F2 values of vowel onsets and middle parts as a function of the vowel openness and type of prominence. The results obtained were interpreted based on the degree of the openness of the vowels under study: an open vowel under emphatic stress tends to expand its vowel space by a backward displacement while close vowels tend to move forward in the mouth cavity when pronounced with emphatic stress.

Changes in Speech Production Following Perceptual Training With Orofacial Somatosensory Inputs.

Orofacial somatosensory inputs play an important role in speech motor control and speech learning. Since receiving specific auditory-somatosensory inputs during speech perceptual training alters speech perception, similar perceptual training could also alter speech production. We examined whether the production performance was changed by perceptual training with orofacial somatosensory inputs. We focused on the French vowels /e/ and /ø/, contrasted in their articulation by horizontal gestures. Perceptual training consisted of a vowel identification task contrasting /e/ and /ø/. Along with training, for the first group of participants, somatosensory stimulation was applied as facial skin stretch in backward direction. We recorded the target vowels uttered by the participants before and after the perceptual training and compared their F1, F2, and F3 formants. We also tested a control group with no somatosensory stimulation and another somatosensory group with a different vowel continuum (/e/-/i/) for perceptual training. Perceptual training with somatosensory stimulation induced changes in F2 and F3 in the produced vowel sounds. F2 decreased consistently in the two somatosensory groups. F3 increased following the /e/-/ø/ training and decreased following the /e/-/i/ training. F2 change was significantly correlated with the perceptual shift between the first and second half of the training phase in the somatosensory group with the /e/-/ø/ training, but not with the /e/-/i/ training. The control group displayed no effect on F2 and F3, and just a tendency of F1 increase. The results suggest that somatosensory inputs associated to speech sound inputs can play a role in speech training and learning in both production and perception.

Where does the gamma go?: Acoustics of the non-labialized voiced velar approximant in Tlingit

The acoustic properties of the voiced velar approximant [ɰ] are poorly characterized, partly from understudy of relevant languages and partly from uncertainty about the sound itself. We investigate this sound in Tlingit, a critically endangered indigenous language of northwestern North America, where [ɰ] contrasts with labialized [w] and palatal [j] in some dialects but not in others where it was lost through sound change (reductive primary split with merge). We use audio recordings of spoken narratives spanning much of the 20th century from speakers with and without [ɰ] to characterize this sound both dialectally and diachronically. We measure formants (f1–f3) to identify place information, amplitude for oral aperture, and harmonic-to-noise ratio for manner. Existing descriptions and phonological patterns predict that [ɰ] is an approximant and not a fricative so we compare against known approximants for differences in turbulence and spectral properties. We also compare against labialized sounds including contrastive [w] for absence of lowered f3 to exclude lip rounding in [ɰ]. We argue that it is the intersection of these acoustic cues that distinguishes [ɰ] from similar sounds, but that these cues are unstable so that dialectal sound change arises from misperception in perturbations of their production.

Comparison of speech changes caused by four different orthodontic retainers: a crossover randomized clinical trial.

This study aimed to compare the influence of four different maxillary removable orthodontic retainers on speech. Eligibility criteria for sample selection were: 20-40-year subjects with acceptable occlusion, native speakers of Portuguese. The volunteers (n=21) were divided in four groups randomized with a 1:1:1:1 allocation ratio. The four groups used, in random order, the four types of retainers full-time for 21 days each, with a washout period of 7-days. The removable maxillary retainers were: conventional wraparound, wraparound with an anterior hole, U-shaped wraparound, and thermoplastic retainer. Three volunteers were excluded. The final sample comprised 18 subjects (11 male; 7 female) with mean age of 27.08 years (SD=4.65). The speech evaluation was performed in vocal excerpts recordings made before, immediately after, and 21 days after the installation of each retainer, with auditory-perceptual and acoustic analysis of formant frequencies F1 and F2 of the vowels. Repeated measures ANOVA and Friedman with Tukey tests were used for statistical comparison. Speech changes increased immediately after conventional wraparound and thermoplastic retainer installation, and reduced after 21 days, but not to normal levels. However, this increase was statistically significant only for the wraparound with anterior hole and the thermoplastic retainer. Formant frequencies of vowels were altered at initial time, and the changes remained in conventional, U-shaped and thermoplastic appliances after three weeks. The thermoplastic retainer was more harmful to the speech than wraparound appliances. The conventional and U-shaped retainers interfered less in speech. The three-week period was not sufficient for speech adaptation.

Arabic vowels characterization and classification using the normalized energy relating to formants and pitch

Vowels are the primary units of a sound system of a language. The classification of these vowels is therefore very important for the recognition and synthesis of speech. In this paper, we propose a normalized energy-based approach in formants and pitch to characterize Arabic vowels (short vowels: / a /, / i /, / u /; long vowels: / a: /, / i: /, / u: /). The classification was performed using a developed algorithm on records extracted from an Arabic corpus after the extraction of the pitch and the first three formants and the computation of the normalized energy in these bands. The results showed that the algorithm distinguishes Arabic vowels by analyzing the normalized energy in the nucleus of F1, F2, and F3 formants and pitch F0 with a rate of 88.7% for long vowels and a rate of 90% for short vowels.

Effective Vowel Stimuli for Measuring Occlusion Effect in the Pediatric Population

Past studies have reported that there are higher sound-pressure levels for each vowel in a child’s ear canal than those in adults due to reduced volume and a shorter ear canal. Furthermore, longer vocal tracts are associated with lower formant frequencies, and vice versa. The structural differences in this regard may reflect the difference in the occlusion effect. Thus, the present study compares the sound pressure levels (SPLs) and first formant frequencies of children and adults with normal hearing and determines the best vowel stimulus to assess the occlusion effect. A repeated measures research design was utilized to investigate the best stimulus with which to measure the occlusion effect among children and adults. Group 1 included ten children, and Group 2 comprised ten adults with normal hearing. The SPLs at frequencies between 200 Hz and 1000 Hz for three uttered vowels, with steps of 100 Hz, were measured using a hearing aid analyzer. The recorded vowels were saved in a ‘.wav’ format for formant frequency analysis. Furthermore, a paired comparison method was used to identify the vowel stimulus that most effectively induced the occlusion effect. A significantly higher SPL was observed for children compared to adults for each vowel. The formant frequency F1 value was higher for children than adults for each vowel, constituting a significant finding. In the paired comparison, the occlusion effect was reported to be significantly greater with respect to the vowel /u/ among adults, while it was reported to be greater in relation to the vowel /i/ among children. The vowel /u/ was the best stimulus with which to assess the occlusion effect among adults. The vowel /i/ was the best stimulus with which to assess the occlusion effect among children.

Impact of 3-dimensional anatomical changes secondary to orthognathic surgery on voice resonance and articulatory function: a prospective study

An evaluation was made of the impact of orthognathic surgery (OS) on speech, addressing in particular the effects of skeletal and airway changes on voice resonance characteristics and articulatory function. A prospective study was carried out involving 29 consecutive patientssubjected to OS. Preoperative, and short and long-term postoperative evaluations were made of anatomical changes (skeletal and airway measurements), speech evolution (assessed objectively by acoustic analysis: fundamental frequency, local jitter, local shimmer of each vowel, and formants F1 and F2 of vowel /a/), and articulatory function (use of compensatory musculature, point of articulation, and speech intelligibility). These were also assessed subjectively by means of a visual analogue scale. Articulatory function after OS showed immediate improvement and had further progressed at one year of follow up. This improvement significantly correlated with the anatomical changes, and was also notably perceived by the patient. On the other hand, although a slight modification in vocal resonance was reported and seen to correlate with anatomical changes of the tongue, hyoid bone, and airway, it was not subjectively perceived by the patients. In conclusion, the results demonstrated that OS had beneficial effects on articulatory function and imperceptible subjective changes in a patient’s voice. Patients subjected to OS, apart from benefitting from improved articulatory function, should not be afraid that they will not recognise their voice after treatment.

Detecting somatisation disorder via speech: introducing the Shenzhen Somatisation Speech Corpus

ObjectiveSpeech recognition technology is widely used as a mature technical approach in many fields. In the study of depression recognition, speech signals are commonly used due to their convenience and ease of acquisition. Though speech recognition is popular in the research field of depression recognition, it has been little studied in somatisation disorder recognition. The reason for this is the lack of a publicly accessible database of relevant speech and benchmark studies. To this end, we introduced our somatisation disorder speech database and gave benchmark results. MethodsBy collecting speech samples of somatisation disorder patients, in cooperation with the Shenzhen University General Hospital, we introduced our somatisation disorder speech database, the Shenzhen Somatisation Speech Corpus (SSSC). Moreover, a benchmark for SSSC using classic acoustic features and a machine learning model was proposed in our work. ResultsTo obtain a more scientific benchmark, we compared and analysed the performance of different acoustic features, i. e., the full ComPare feature set, or only Mel frequency cepstral coefficients (MFCCs), fundamental frequency (F0), and frequency and bandwidth of the formants (F1-F3). By comparison, the best result of our benchmark was the 76.0% unweighted average recall achieved by a support vector machine with formants F1–F3. ConclusionThe proposal of SSSC may bridge a research gap in somatisation disorder, providing researchers with a publicly accessible speech database. In addition, the results of the benchmark could show the scientific validity and feasibility of computer audition for speech recognition in somatization disorders.

Spectral Characteristics of Cardinal Vowels as Indicators of the Auditory Speech Feedback Control in Patients with Moderate and Moderately Severe Chronic Postlingual Sensorineural Hearing Loss

Chronic sensorineural hearing loss (SNHL) is characterized by an increase in hearing thresholds at basic speech frequencies, which implies the auditory speech feedback control worsening and, as a result, changes of speech characteristics. A hypothesis was tested that such worsening can manifest itself in an increase of F0, F1, F2 formants of speech vowel sounds in patients with moderate and moderately severe postlingual SNHL. Recordings of elicited speech were performed for young and middle age women (36–59 years): 7 women speakers with moderate SNHL who did not use hearing aids; 5 women speakers with moderately severe SNHL who were hearing aid users but were not using them during the recordings; a control group of 12 normally hearing women speakers. An assessment of F0, F1 and F2 of stressed vowels [a], [i], [u] and calculations of vowels’ centralization indices – vowel space area, vowel formant centralization ratio and the second formant ratio (F2i/F2u), were performed. All the studied spectral indices in groups of patients with postlingual SNHL were similar to those in the control group, no statistically reliable differences were revealed.

Effect of telepractice on pediatric cochlear implant users and provider vowel space: A preliminary report

Clear speaking styles are goal-oriented modifications in which talkers adapt acoustic-phonetic characteristics of speech to compensate for communication challenges. Do children with hearing loss and a clinical provider modify speech characteristics during telepractice to adjust for remote communication? The study examined the effect of telepractice (tele-) on vowel production in seven (mean age 4:11 years, SD 1:2 years) children with cochlear implants (CIs) and a provider. The first (F1) and second (F2) formant frequencies of /i/, /ɑ/, and /u/ vowels were measured in child and provider speech during one in-person and one tele-speech-language intervention, order counterbalanced. Child and provider vowel space areas (VSA) were calculated. The results demonstrated an increase in F2 formant frequency for /i/ vowel in child and provider speech and an increase in F1 formant frequency for /ɑ/ vowel in the provider speech during tele- compared to in-person intervention. An expansion of VSA was found in child and provider speech in tele- compared to in-person intervention. In children, the earlier age of CI activation was associated with larger VSA in both tele- and in-person intervention. The results suggest that the children and the provider adjust vowel articulation in response to remote communication during telepractice.

Ingo’s Register Treadmill

Ingo's Register Treadmill Ingo Titze (bio) VOICE RESEARCH AND TECHNOLOGY A register treadmill was proposed eight years ago as a diagnostic exercise for exposing involuntary register shifts in the D4 to A4 pitch range.1 The basic concept was to create pitch and vowel progressions that would elicit maximum crossings of harmonics with supraglottal resonances (formants) of the vocal tract. It is well known that sudden increases or decreases in harmonic amplitudes in proximity of a resonance can cause a timbral change that can be considered an acoustic registration.2 In particular, strengthening or weakening the second harmonic with the first formant can be responsible for such a register shift. A pentavowel sequence, combined with a pentatonic scale, was proposed such that source frequencies move in opposite direction to resonance frequencies. This produces multiple harmonic-resonance crossovers. This article is a follow-up to expand the treadmill to include a wider pitch range and sex differences in formant frequencies. While allophonic variations of formants F1 and F2 are large across individuals and languages, a smoothed penta-vowel sequence has been chosen here. Each sequence begins with a wide mouth shape and ends with a narrow mouth shape. Formant frequencies for females have been chosen to be 20 % higher than for males. All formant frequencies are listed below for two vowel sequences. High Vowel Sequence [æ] [ɛ] [e] [ɪ] [i] Male F1 670 550 420 350 280 Female F1 860 660 504 420 320 Male F2 1800 1900 2000 2200 2300 Female F2 2160 2280 2400 2640 2760 Low Vowel Sequence [a] [Ɔ] [o] [Ʊ] [u] Male F1 850 500 360 300 300 Female F1 1020 600 431 360 370 Male F2 1610 800 640 610 595 Female F2 1932 960 768 732 714 In the treadmill, F1 is descending while fo is ascending to produce a maximum number of harmonic/formant crossings. Figure 1 shows the graphic display for a D4–A4 up and down pentatonic scale (solid lines), combined with the low vowel formant frequencies (dashed lines). Note that there are [End Page 197] Click for larger view View full resolution Figure 1. Treadmill for the D4–A4 pentatonic scale produced on low vowels; (a) male sequence and (b) female sequence. five crossings on the ascending scale for both males and females. For males, the crossings are: fo crosses F1 near the [o] vowel; 2fo crosses F1 near the [Ɔ] vowel 2fo crosses F2 near the [o] vowel 3fo crosses F2 near the [Ɔ] vowel 4fo crosses F2 near the [Ɔ] vowel. Note the importance of the [Ɔ] and [o] vowels in males in this region of the pitch range. For females, the same five crossings occur, but on slightly more closed-mouth vowels due to higher overall formant frequencies. For example, fo crosses F1 closer to the [Ʊ] vowel than the [o] vowel. Figure 2 shows the treadmill for the high vowel sequence. The pentatonic scale is kept the same, D4–A4. There are now only two major crossings: fo crosses F1 between [e] and [I] in males and between [I] and [i] in females; 2fo crosses F2 between [æ] and [ɛ] in males and between [ɛ] and [e] in females None of the first 4 harmonics cross the second formant F2. Thus, in this region of the pitch range (D4–A4), acoustic registration in high vowels is carried primarily by the first two harmonics. The fifth and higher harmonics are not plotted. They will interact with F2 and higher formants, particularly if fo is raised. Figures 3 and 4 show the treadmills when the pentatonic scale is raised to the G4–D5 range. Usually one progresses in half-steps to this higher level. Most of the high pitch range for males and female belters is then covered. Figure 3 shows the low vowel sequence. The bright [a] vowel is now included in the crossings, but the general picture has not changed much from the A4–D4 scale. Of special...

Вариативность гласных и ее зависимость от типа ударения и фразовой позиции

The position of vowels in acoustic space is described using the values of the F1 and F2 formants. The approach is determined by the need to perceptually distinguish neighboring vowels. The area occupied by a specific vowel is described as a combination of microfields with each microfield formed by a set of allophone positions of the vowel in question. The results obtained demonstrate that the variability of the allophone position in the acoustic field can be determined by a number of factors, such as the degree of prominence and vowel position in the phrase. With this aim vowel positioning in the acoustic space in words with neutral and emphatic stress was studied. The speech material for analysis comprised the word 'Stas' embedded in the carrier phrase 'Stas ne byl tihoney' ('Stas was not quiet') with the target word occupying initial, medial and final positions in the phrase; in each position the word was pronounced with neutral and emphatic stress. F1 and F2 values of the sound [a] in the word 'Stas' were extracted with the FFT method using the Praat software. The Student paired t-test was employed to note the significance of difference between the first and second formant frequencies of neutrally and emphatically stressed vowels. The analysis revealed that the vowels uttered with emphatic stress are characterized by an expansion of their acoustic vowel space by moving off the vowel space center. The displacement occurs either through an increase of F1, a decrease of F2, or both. A general trend was observed in the impact of phrasal position on vowel formant frequencies. Though the vowels under neutral stress seemed to display greater response to the phrasal position factor compared to the emphatically stressed ones, noticeable regularities could not be established due to a high intradialectal variability of speakers.

Egyptian vowel second formant in isolation and in transition following high-frequency fricatives by NLFC hearing aid in children: how does the pattern compare to typically hearing peers?

BackgroundHigh-frequency consonants form an area of difficulty among children with hearing impairment. Many technological setups have emerged in order to improve their audibility, among them nonlinear frequency compression (NLFC). Therefore, the following study was carried out in order to evaluate change in production of high-frequency fricatives by hearing-impaired children utilizing NLFC hearing aids. This was through spectrographic analysis of F2 onset of transition elicited by fricatives in a prevocalic context, and results were compared to typically developing (TD) children. A change in mid-frequency sounds due to high-frequency compression was also tested through production of sustained vowels in isolation.ResultsA preliminary prospective case-control study involved 9 patients with NLFC hearing aids, evaluated at 1- and at 6-month post-fitting, without receiving speech therapy. Spectrographic analysis of F2 formant onset in [a] and [i] vowels when combined with [s] and [f] fricatives in a CV (consonant-vowel) pattern, presented auditorily and audio-visually, was observed and analyzed. One patient was excluded due to noncompliance in attendance. In the 8 patients who completed the study, very high-frequency level of F2 onset in CV was notable in second versus first evaluation in NLFC group, to the extent of surpassing the typical value in TD control group with [i] vowel. Contrastingly, F2 of sustained vowels in isolation took a trend of a lower value after 6 months of NLFC hearing aid use, as compared to the first evaluation. Consequently, the gap between sustained vowel F2 level in TD and NLFC groups widened.ConclusionMean high-frequency range of F2 onset of transition in CV patterns of voiceless fricatives [s] and [f] with [i] and [a] vowels 6 months after NLFC fitting reflects an enhancement in the frequency range production of these sounds. A shift toward a lower F2 frequency range in sustained mid-frequency vowels, on the other hand, remains to be carefully investigated as a sequel of nonlinear frequency compression in the Egyptian hearing-impaired children.

Iconic Associations Between Vowel Acoustics and Musical Patterns, and the Musical Protolanguage Hypothesis

Vowels are the most musical and sonic elements of speech. Previous studies found non-arbitrary associations between vowel intrinsic pitch and musical pitch in senseless syllables. In songs containing strings of senseless syllables, vowels are connected to melodic direction in close correspondence to their intrinsic pitch or the frequency of the second formant F2. This paper shows that also vowel intrinsic duration is related to musical patterns. It is generally assumed that low vowels like [a ɔ o] have a higher intrinsic duration than high vowels like [i y u] and that there is a positive correlation between the first formant F1 and duration. Analyzing 20 traditional Alpine yodels I found that vowels with longer intrinsic duration tend to align with longer notes, whereas vowels with shorter intrinsic duration with shorter notes. This new result might shed some light on size-sound symbolism in general: Since there is a direct match between vowel intrinsic duration and the “size” of musical notes, there is no need to explain the “size” of musical notes via Ohala's “frequency code” hypothesis. Moreover, I will argue that the iconic associations found between vowel acoustics and musical patterns support the idea of a sound-symbolic musical protolanguage. Such a protolanguage may have started with vowel syllables conveying pitch, timbre, as well as emotional, indexical, and sound-symbolic information.

Impact of Startling Acoustic Stimuli on Word Repetition in Individuals With Aphasia and Apraxia of Speech Following Stroke.

The StartReact effect, whereby movements are elicited by loud, startling acoustic stimuli (SAS), allows the evaluation of movements when initiated through involuntary circuitry, before auditory feedback. When StartReact is applied during poststroke upper extremity movements, individuals exhibit increased muscle recruitment, reaction times, and reaching distances. StartReact releases unimpaired speech with similar increases in muscle recruitment and reaction time. However, as poststroke communication disorders have divergent neural circuitry from upper extremity tasks, it is unclear if StartReact will enhance speech poststroke. Our objective is to determine if (a) StartReact is present in individuals with poststroke aphasia and apraxia and (b) SAS exposure enhances speech intelligibility. We remotely delivered startling, 105-dB white noise bursts (SAS) and quiet, non-SAS cues to 15 individuals with poststroke aphasia and apraxia during repetition of six words. We evaluated average word intensity, pitch, pitch trajectories, vowel formants F1 and F2 (first and second formants), phonemic error rate, and percent incidence of each SAS versus non-SAS-elicited phoneme produced under each cue type. For SAS trials compared to non-SAS, speech intensity increased (∆ + 0.6 dB), speech pitch increased (∆ + 22.7 Hz), and formants (F1 and F2) changed, resulting in a smaller vowel space after SAS. SAS affected pitch trajectories for some, but not all, words. Non-SAS trials had more stops (∆ + 4.7 utterances) while SAS trials had more sustained phonemes (fricatives, glides, affricates, liquids; ∆ + 5.4 utterances). SAS trials had fewer distortion errors but no change in substitution errors or overall error rate compared to non-SAS trials. We show that stroke-impaired speech is susceptible to StartReact, evidenced by decreased intelligibility due to altered formants, pitch trajectories, and articulation, including increased incidence of sounds that could not be produced without SAS. Future studies should examine the impact of SAS on voluntary speech intelligibility and clinical measures of aphasia and apraxia.

The time course of first formant movement in normal and loud speech

Louder speech tends to be slower than typical speech. For some vowels (viz., low and lax ones), louder speech may also be associated with higher first formant frequencies (F1s) at vowel midpoint. Possibly, increased duration allows speakers more time to reach a lower jaw position, thus a higher value of F1, in loud speech. In earlier work, we found that some loudness differences appeared at 25% and 75% of vowel durations, i.e., they were seen for much of the vowel. The current study presents data from 11 German-speaking women producing naturally elicited typical and loud speech. Target words included high, low, tense, and lax vowels with surrounding consonantal place controlled. We will present full vowel trajectories, i.e., from preceding to following consonants, to assess the time course of F1 differences across vowel types and loudness conditions. F1 will also be considered within normalized time intervals to control for durational differences between conditions. We expect that F1 formant trajectories will show minimal loudness differences throughout the vowel for high tense vowels, but time-varying differences will be more apparent for low and lax vowels, and appear rather early in the vowel.