Sibilant production in Hebrew-speaking adults: Apical versus laminal

Self-perception of tongue tip constriction in alveolar fricatives produced by young women with and without normal tongue positioning

PURPOSE

This study investigated the self-perception of 49 women, monolingual speakers of Brazilian Portuguese, about their tongue position for the alveolar articulation of the fricatives [s] and [z].

METHODS

The video recording of speech samples of these 49 women (ages 18 to 28) were analyzed by three Speech-Language Pathologists. They were classified into two groups: Group 1 (G1, n=25), with no alterations in the tongue position during the production of [s] and [z], and Group 2 (G2, n=24), with alterations in the tongue position during the production of [s] and [z]. The tongue position self-perception experiment required the participants to identify the specific tongue constriction point in the production of [s] and [z] (apical, laminal, or "other") during the reading of 24 words and 24 pseudowords. The Friedman test, with posterior paired comparisons, was used for the intragroup analysis. The Mann-Whitney test was used for intergroup comparisons. The statistical significance adopted was 5% (p<0.05).

RESULTS

G1 reported apical and laminal tongue constrictions while GE reported these constrictions plus other tongue adjustments. The presence of other tongue adjustments differentiated the groups, G1 and G2 (p=0,002). There were significant differences between [s] and [z] for G1, with the laminal position occurring more often in [s] compared to [z].

CONCLUSION

Women with and without alteration in the tongue position reported apical and laminal constrictions. Howerer, other tongue adjustments were self-perceived in the presence of altered tongue position.

Improving speech characteristics of young adults with congenital dysarthria: An exploratory study comparing articulation training and the Beatalk method

INTRODUCTION

This exploratory study compared the effects of two speech therapy approaches on speech characteristics of young adults with congenital dysarthria resulting from various etiologies: a) articulation training focusing on consonant articulation exercises at various levels (isolation, syllables, and words), and b) the Beatalk method, based on human beatboxing, i.e., producing various instrumental sounds in an a-cappella musical context. Both interventions were designed to increase participants' speech intelligibility.

METHODS

Twelve adults with congenital dysarthria and reduced speech intelligibility participated in treatment groups for eight weeks. Six participants were assigned to the articulation training group, and six to the Beatalk group. Intelligibility of single words and continuous speech, voice measures, and oral-diadochokinesis rates were measured before and after the treatment.

RESULTS

The results showed that the Beatalk intervention yielded a significant overall pre- to post-treatment effect. Specifically, it resulted in gains in articulatory accuracy and intelligibility for single words. Improvements were not noted following articulation training.

CONCLUSIONS

The results present initial evidence of the positive effect of the Beatalk method as an intervention tool for adults with congenital dysarthria. This relatively easy-to-learn technique shows promise, as it involves intense and repetitive production of speech sounds while controlling rhythm and breathing in an enjoyable context.

Evaluating rate and accuracy of real word vs. non-word diadochokinetic productions from childhood to early adulthood in Hebrew speakers

BACKGROUND

Oral-Diadochokinesis (oral-DDK) tasks measure how quickly and accurately one can repeat a series of target sounds. Thus, they are a popular tool for evaluating oral-motor skills for individuals with various speech disorders. Typically, oral-DDK tasks involve rapid repetition of non-words. For several populations (e.g., young children, older adults), it has been suggested that repetitions of real words may be more suitable, commonly resulting in faster rates. Yet, the literature is either silent or inconsistent regarding this real-word repetition advantage for other age groups, from preschoolers to young adults. It is not clear whether performance accuracy is affected as well. Specifically, for Hebrew speakers, this data is missing.

AIMS

The goal of this study was to compare rate and accuracy for non-word and real-word repetition, in four groups of Hebrew-speaking individuals; preschoolers (5 years old), younger elementary school children (7 years old), adolescents (15 years old) and young adults (25 years old). Secondary goals were to provide a developmental pattern for oral-DDK rates for Hebrew speakers, and to compare it to the English norms.

METHODS & PROCEDURES

All participants (n=150) had typical speech and language development. They were asked to repeat "pataka" (non-word) and "bodeket" (Hebrew real word) as quickly and accurately as possible for 10 sec. Production rates (syllables per second) and accuracy (on a 5-point scale) were measured.

OUTCOMES & RESULTS

As expected, oral-DDK rates gradually increased with age, with similar rates for both real- and non-words. Accuracy scores were higher for real- than non-word repetition, across all age groups. For the group of school-age children, the Hebrew rates differed from the English ones.

CONCLUSIONS & IMPLICATIONS

A real-word repetition advantage was documented only for repetition accuracy, but not for rate. These findings can be explained as each stimulus involves different demands on an individual's neuro-motor and linguistic processing abilities. Further research using real- and non-word tasks should be conducted with clinical populations to assess whether both procedures could assist in differential diagnosis between various speech disorders. Finally, the large differences between children of different ages, as well as the apparent rate differences between Hebrew and English, highlight the need to create age- and language-sensitive norms.

Acoustic vowel analysis and speech intelligibility in young adult Hebrew speakers: Developmental dysarthria versus typical development

BACKGROUND

Developmental dysarthria is a motor speech impairment commonly characterized by varying levels of reduced speech intelligibility. The relationship between intelligibility deficits and acoustic vowel space among these individuals has long been noted in the literature, with evidence of vowel centralization (e.g., in English and Mandarin). However, the degree to which this centralization occurs and the intelligibility-acoustic relationship is maintained in different vowel systems has yet to be studied thoroughly. In comparison with American English, the Hebrew vowel system is significantly smaller, with a potentially smaller vowel space area, a factor that may impact upon the comparisons of the acoustic vowel space and its correlation with speech intelligibility. Data on vowel space and speech intelligibility are particularly limited for Hebrew speakers with motor speech disorders.

AIMS

To determine the nature and degree of vowel space centralization in Hebrew-speaking adolescents and young adults with dysarthria, in comparison with typically developing (TD) peers, and to correlate these findings with speech intelligibility scores.

METHODS & PROCEDURES

Adolescents and young adults with developmental dysarthria (secondary to cerebral palsy (CP) and other motor deficits, n = 17) and their TD peers (n = 17) were recorded producing Hebrew corner vowels within single words. For intelligibility assessments, naïve listeners transcribed those words produced by speakers with CP, and intelligibility scores were calculated.

OUTCOMES & RESULTS

Acoustic analysis of vowel formants (F1, F2) revealed a centralization of vowel space among speakers with CP for all acoustic metrics of vowel formants, and mainly for the formant centralization ratio (FCR), in comparison with TD peers. Intelligibility scores were correlated strongly with the FCR metric for speakers with CP.

CONCLUSIONS & IMPLICATIONS

The main results, vowel space centralization for speakers with CP in comparison with TD peers, echo previous cross-linguistic results. The correlation of acoustic results with speech intelligibility carries clinical implications. Taken together, the results contribute to better characterization of the speech production deficit in Hebrew speakers with motor speech disorders. Furthermore, they may guide clinical decision-making and intervention planning to improve speech intelligibility. What this paper adds What is already known on the subject Speech production and intelligibility deficits among individuals with developmental dysarthria (e.g., secondary to CP) are well documented. These deficits have also been correlated with centralization of the acoustic vowel space, although primarily in English speakers. Little is known about the acoustic characteristics of vowels in Hebrew speakers with motor speech disorders, and whether correlations with speech intelligibility are maintained. What this paper adds to existing knowledge This study is the first to describe the acoustic characteristics of vowel space in Hebrew-speaking adolescents and young adults with developmental dysarthria. The results demonstrate a centralization of the acoustic vowel space in comparison with TD peers for all measures, as found in other languages. Correlation between acoustic measures and speech intelligibility scores were also documented. We discuss these results within the context of cross-linguistic comparisons. What are the potential or actual clinical implications of this work? The results confirm the use of objective acoustic measures in the assessment of individuals with motor speech disorders, providing such data for Hebrew-speaking adolescents and young adults. These measures can be used to determine the nature and severity of the speech deficit across languages, may guide intervention planning, as well as measure the effectiveness of intelligibility-based treatment programmes.

Quantifying Tongue Tip Shape in Apical and Laminal /s/: Contributions of Palate Shape

Purpose Anterior tongue shape during /s/ production is often described as "tip-up" or apical, versus "tip-down" or laminal. Typically, this is determined by observing the shape of the anterior midline tongue. The purpose of this study was to identify methods of curvature calculation that quantify the observed shape differences and to examine whether the shape differences were affected by palate shape. Previous work shows that palate height has some effect (Grimm et al., 2017). Method Four curvature-based measures were applied to a series of points selected along the tongue surface in midsagittal cine magnetic resonance images during speech. The measures were minimal curvature, averaged largest curvature (ALC), normalized ALC, and interpolated normalized ALC. These measures were compared to visual judgments of apical and laminal /s/. Anterior palate shape was measured from dental casts. Results The apical /s/ contained a flat or concave region in the anterior tongue, while the laminal /s/ had a convex shape along the entire tongue. Thus, the laminal shape was less complex than the apical. The last 2 metrics, based on averages of multiple normalized curvatures, captured this complexity difference. Subjects with a more steeply sloped anterior palate tended to use laminal /s/. Conclusions The tongue shape for the 2 /s/ types was best defined by complexity of the shape, rather than local anterior shape. Statistical quantities that measured curvature in multiple locations, and normalized across subjects, were best at distinguishing the 2 /s/ shapes. Interpolating additional points between the manually selected ones did not improve the method. Supplemental Material https://doi.org/10.23641/asha.9733709.

Introducing the Beatalk technique: using beatbox sounds and rhythms to improve speech characteristics of adults with intellectual disability

BACKGROUND

Individuals with intellectual disability (ID) often demonstrate speech impairments and reduced intelligibility. However, traditional treatment methods, which involve using repetitive verbal and non-verbal exercises, may not be fully suitable for this population. As adults with ID tend to lose interest and motivation facing the demands of a typical speech therapy session, other intervention methods are needed. The current study tested a novel intervention technique, Beatalk, based on practising vocally produced sounds and rhythms, imitating the sounds produced by rhythm machines in an a cappella musical context (i.e., human beatboxing). Human beatboxing may be a particularly effective tool since it involves intense production of speech sounds (phonemes) that can be misarticulated in the presence of speech disorders; it is relatively easy to learn and practice, and is also considered 'fun'.

AIMS

As many of the features of beatboxing make it a promising method for speech therapy, this pioneering study aimed to examine its effectiveness in comparison with a traditional speech therapy.

METHODS & PROCEDURES

Twelve adults with moderate ID and low speech intelligibility (age 24-48 years) participated in a speech therapy group for 6 weeks. Six participants were assigned to the Beatalk (study) group and six to a traditional (control) therapy group. Pre- to post-treatment changes in speech intelligibility and voice measures were assessed.

OUTCOMES & RESULTS

The preliminary data demonstrate that both types of therapy groups resulted in improved performance in articulation accuracy and voice measures, yet the Beatalk technique yielded larger gains.

CONCLUSIONS & IMPLICATIONS

The results present initial evidence for the beneficial effect of the Beatalk technique as an intervention tool for adults with ID. It is an easy-to-use technique in the context of speech therapy, and may enhance verbal communication skills in this population.

The "Morning Voice": The Effect of 24 Hours of Sleep Deprivation on Vocal Parameters of Young Adults

Fatigue following sleep deprivation adversely affects various aspects of human performance. It also induces recognizable voice changes, but the literature is inconsistent regarding their nature. The current study used acoustical analyses to assess the effect of 24 hours of sleep deprivation on vocal parameters of young adults. Forty-seven participants (23 females and 24 males) were tested after nocturnal sleep and after 24 hours of sleep deprivation. Different voice samples were recorded (sustained phonation, words, and sentences) and analyzed for fundamental frequency (F₀, in Hz), vocal intensity (in dB), harmonic-noise ratio (HNR, in dB), jitter, and shimmer (in %). The main finding was significantly higher HNR values following sleep deprivation than nocturnal sleep for females, across all voice samples. The HNR is a measure of the degree of acoustic periodicity, or the amount of noise compared to the harmonic quality present in the voice. As its values are higher, the voice quality is perceptually better. The current results indicate that females had a significantly higher ratio of vocal harmonics compared to vocal noise when they were sleep deprived. In contrast, following nocturnal sleep, the ratio of vocal harmonics compared to vocal noise was lower, which means the voice quality was poorer. This may explain the common perceptual impressions of decreased voice quality after sleep, which may be more pronounced in females.