Optimizing stimulus length for clinical nasalance measures in Swedish

Standardized passages used for speech nasalance measures may be too long for clinical use with very young or non-compliant patients. The aim of this study was to establish whether nasalance scores from shorter sections of three Swedish speech stimuli were equivalent to those from their corresponding whole stimulus. Nasalance recordings for three Swedish speech stimuli (oral, nasal and oronasal) were obtained from 29 typically developing Swedish children (7-11 years). Cumulative sentence combinations were evaluated for equivalence to their respective whole passages according to two different criteria: one based on t-testing and the other on cumulative frequencies of score differences. Results showed that shorter sequences of sentences could be considered equivalent to the whole passage for the oral and nasal stimuli, provided that the sentences were sequenced in order of increasing difference from the whole stimulus score and that those sentences with scores significantly different from the whole passage score were not included.     

Normative nasalance scores in the production of words and syllables for Brazilian Portuguese speakers

The objective of this study was to determine normative nasalance scores for non-cleft children, adolescents and adults, native speakers of Brazilian Portuguese, during the production of words and syllables, for cross-linguistic comparisons in populations with and without cleft palate. Nasalance was assessed in 62 individuals, aged 6–10 years (n = 20), 11–17 years (n = 20) and 18–35 years (n = 22), using a nasometer II model 6450 (KayPENTAX), during production of one sequence of nine oral words (pipa, bis, burro, tatu, pilha, cuca, gui, fila, luz) and of sequences of isolated syllables (e.g. pa, pa, pa, pa, pa, pa) composed of plosive, fricative, liquid and nasal consonants with high and low vowels. In order to validate the new nasalance stimuli, nasalance scores for traditional oral and nasal stimuli were also obtained. Differences were analyzed at a significance level of 0.01. Mean nasalance scores (±SD) during the production of the sequence of words were 18 ± 5% (children), 18 ± 7% (adolescents) and 21 ± 5% (adults). Differences between age groups were not significant. During the production of syllables, adults had the highest mean nasalance scores (except for syllable /mi/); significant differences between age groups were observed only for /pa/ ,/sa/ and /la/. Nasalance scores were significantly higher in oral and nasal syllables with high vowels than with low vowels, and in nasal syllables than in oral syllables with high and low vowels. The nasalance scores obtained for the sentences were comparable to previously established norms. In conclusion, the nasalance scores defined for Brazilian Portuguese speakers, in different stimuli, may be adopted as normative values for local and cross-language comparisons in the identification of hypernasality related to conditions such as cleft palate, neurogenic disorders and syndromes.     

Acknowledgements,questions, and additional resources

The purposes of this study were to derive nasalance norms for monolingual Greek speakers, to examine nasalance scores as a function of gender and to draw cross-linguistic comparisons based on normative data.

Participants read aloud a corpus of linguistic material, consisting of (1) a nasal text, an oral text and a balanced text; (2) a set of nasal sentences and four sets of oral sentences and (3) repetitions of each of 12 syllable types (8 oral and 4 nasal). The last two sets of material corpus were based on an adaptation of the Simplified Nasometric Assessment Procedures Test (SNAP test) test () in Greek, called the G-SNAP test. Eighty monolingual healthy young adult speakers of Greek, 40 males (mean age = 21 years) and 40 females (mean age = 20.5 years), with normal hearing and speech characteristics and unremarkable history were included in the study.

The Nasometer (model 6200-3) was used to derive nasalance scores. Mean normative nasalance for spoken Greek was 25.50%, based on the G-oronasal text (with 8.6% nasals). Nasalance scores did not differ significantly with respect to gender. Finally, spoken Greek consistently yielded lower nasalance scores than other languages examined in past work.

The aforementioned normative data on nasalance of young adult speakers of Greek are valid across gender and have direct clinical utility as they provide valuable reference information for the diagnosis and management of Greek adults with resonance disorders caused by velar dysfunction.     

Nasalance norms in Greek adults

The purposes of this study were to derive nasalance norms for monolingual Greek speakers, to examine nasalance scores as a function of gender and to draw cross-linguistic comparisons based on normative data. Participants read aloud a corpus of linguistic material, consisting of (1) a nasal text, an oral text and a balanced text; (2) a set of nasal sentences and four sets of oral sentences and (3) repetitions of each of 12 syllable types (8 oral and 4 nasal). The last two sets of material corpus were based on an adaptation of the Simplified Nasometric Assessment Procedures Test (SNAP test) test ( MacKay and Kummer, 1994 ) in Greek, called the G-SNAP test. Eighty monolingual healthy young adult speakers of Greek, 40 males (mean age = 21 years) and 40 females (mean age = 20.5 years), with normal hearing and speech characteristics and unremarkable history were included in the study. The Nasometer (model 6200-3) was used to derive nasalance scores. Mean normative nasalance for spoken Greek was 25.50%, based on the G-oronasal text (with 8.6% nasals). Nasalance scores did not differ significantly with respect to gender. Finally, spoken Greek consistently yielded lower nasalance scores than other languages examined in past work. The aforementioned normative data on nasalance of young adult speakers of Greek are valid across gender and have direct clinical utility as they provide valuable reference information for the diagnosis and management of Greek adults with resonance disorders caused by velar dysfunction.     

Dialectal and gender differences in nasalance for a Mandarin population

The purpose of this study was to determine whether there are dialectal and gender related differences in nasalance of main Mandarin vowels and three sentences in 400 Chinese normal adults. The mean nasalance score difference for dialect and gender was significant (p < .001) in all speech materials. For different dialects, the average nasalance scores show that Chongqing > Beijing > Shanghai > Guangzhou for the nasal sentence, oro-nasal sentence, /a/, /i/ and /u/. In addition, the average nasalance scores of females were higher than those of males for all speech materials in all dialects. The clinical significance of this study can be helpful in making nasalance clinical decisions for Chinese people with cleft palate, hearing disorders and dysarthria with resonance disorders. It also shows the theoretical and socio-cultural features for linguists considering dialects and gender.     

Same noses, different nasalance scores: data from normal subjects and cleft palate speakers for three systems for nasalance analysis

Nasalance scores from the Nasometer, the NasalView and the OroNasal System were compared. The data was collected from 50 normal participants and 19 hypernasal patients with cleft palate. The Nasometer had the lowest nasalance scores for the non-nasal Zoo Passage and that the OroNasal System had the lowest nasalance scores for the Nasal Sentences. The nasalance distance was largest for the Nasometer and smallest for the OroNasal System. When the calculation was based on nasalance magnitudes, results for sensitivity ranged from 57.9% to 81.8% and results for specificity ranged from 62.0% to 76.0%. When the calculation was based on nasalance distances, results for sensitivity ranged from 84.2% to 100.0% and results for specificity ranged from 82.0% to 100.0%. Results suggest that nasalance scores from the three systems are not interchangeable. Diagnostic efficacy improved when the calculations were based on nasalance distances rather than magnitudes, but further research is warranted to corroborate these findings.     

Normative data on nasalance scores for Swedish as measured on the Nasometer: Influence of dialect,gender, and age

This study was conducted to establish normative nasalance values for Swedish speaking children as measured with the Nasometer^? II, and to investigate differences due to regional dialect, gender, and age. Two hundred and twenty healthy children aged 4–5, 6–7, and 9–11 years were included. Group mean nasalance scores for four speech stimuli were calculated and compared. There were no significant differences due to dialect or gender for children in the study. For age there was a significant difference on nasal sentences between the youngest group of children and the other two groups, age 4–5 vs age 6–7 (t = ?2.844, p = .006) and for age 4–5 vs age 9–11 (t = ?2.888, p = .005). The results from this study have both clinical significance for Swedish SLPs working with resonance disorders, and theoretical significance for linguists studying features of dialects and languages.     

Tongue-palate contact for nasal versus oral stops in speakers with repaired cleft palate

Most previous studies of speech disorders associated with cleft palate have reported a higher incidence of errors for oral stops, fricatives and affricates compared to nasal stops. However, the results of a recent ultrasound study have raised the possibility that errors affecting nasal consonants might not be as rare as originally thought. A review of the electropalatography (EPG) literature on cleft palate speech has also shown that atypical tongue-palate contact patterns can occur during nasal consonants and that nasal and oral stops are often produced with similar atypical lingual gestures. Therefore, this study investigated the production of nasal stops (/n/and/?/) and the homorganic oral stops (/t/,/d/and/k/,/ɡ/respectively) in eight children with repaired cleft palate using perceptual judgements and evaluation of tongue-palate contact patterns. Results of the perceptual judgements support the findings in the literature that there was a higher per cent phoneme correct for the alveolar nasal (about 90%) than for the oral stops (60–70%). However, there was a low per cent phoneme correct for the velar nasal (about 50%) and the per cent correct as determined by the EPG data was lower than those based on perceptual judgements. Two children showed similar atypical articulatory gestures for the oral and nasal alveolar stops. We discuss the possibility that the nasal errors may be of phonemic as opposed to phonetic origin. The results underscore the importance of considering the phonological dimension of production when assessing the speech of children in this clinical group.     

Latency shifts in the N2b component track phonological deviations in spoken words.

OBJECTIVE: We investigated event-related brain potentials (ERPs) elicited by a novel speech comprehension paradigm modelled after the neuropsychological Token Test. The objective of the study was to determine whether the ERPs were sensitive to differences in the initial phonemes of the speech stimuli. METHODS: Twenty-seven healthy subjects identified incorrect spoken sentences on the computerised Token Test (CTT). The incorrect spoken sentences contained one word that did not match the previously studied animations. The initial phonemes of these words were either different than or similar to the initial phonemes of their correct counterparts. RESULTS: Different initial phonemes were associated with an early N2b, while words having similar initial phonemes resulted in a substantially delayed N2b. CONCLUSION: The delayed latency effect was due to whether the incorrect word's initial phoneme matched or mismatched that of the expected word. In both cases, this component reflected a mismatch with an existing cognitive template maintained in phonological working memory. The results indicate that this mismatching effect reflected primarily attentional detection rather than language processing.     

A normative-speaker validation study of two indices developed to quantify tongue dorsum activity from midsagittal tongue shapes

This study reported adult scores on two measures of tongue shape, based on midsagittal tongue shape data from ultrasound imaging. One of the measures quantified the extent of tongue dorsum excursion, and the other measure represented the place of maximal excursion. Data from six adult speakers of Scottish Standard English without speech disorders were analyzed. The stimuli included a range of consonants in consonant–vowel sequences, with the vowels /a/ and /i/. The measures reliably distinguished between articulations with and without tongue dorsum excursion, and produced robust results on lingual coarticulation of the consonants. The reported data can be used as a starting point for collecting more typical data and for analyzing disordered speech. The measurements do not require head-to-transducer stabilization. Possible applications of the measures include studying tongue dorsum overuse in people with cleft palate, and typical and disordered development of coarticulation.     

The effect of stimulus structure on the auditory-visual perception of speech by Hebrew speaking adults with profound hearing loss

The present study evaluated the effect of speech features and context on the auditory-visual perception of speech by Hebrew speaking adults with profound hearing loss. All participants had profound, sensorineural hearing loss (95 dBHL+). They were presented with the following speech perception materials selected to evaluate the effect of the following variables: (1) /aCa/ nonsense syllables to evaluate the effect of voicing, place and manner of articulation on perception; (2) nonmeaningful and meaningful words to assess the effect of phoneme position; and (3) sentences to evaluate the effect of length, type and knowledge of the topic on perception. Speech material was introduced through the auditory-visual modality. Results indicated that all participants relied mainly on visual information; therefore perception of variables containing more pronounced visual cues was better than that of variables with poor visual information. Front place of articulation, fricatives, initial phonemes and short sentences, for example, were perceived better than back place of articulation, nasals, final phonemes and long sentences respectively. Further research, in which these kinds of speech materials are presented through the different sensory modalities using different sensory devices, is recommended.     

Deciphering phonemes from syllables in blood oxygenation level‐dependent signals in human superior temporal gyrus

Linguistic units such as phonemes and syllables are important for speech perception. How the brain encodes these units is not well understood. Many neuroimaging studies have found distinct representations of consonant–vowel syllables that shared one phoneme and differed in the other phoneme (e.g. /ba/ and /da/), but it is unclear whether this discrimination ability is due to the neural coding of phonemes or syllables. We combined functional magnetic resonance imaging with multivariate pattern analysis to explore this question. Subjects listened to nine Mandarin syllables in a consonant–vowel form. We successfully decoded phonemes from the syllables based on the blood oxygenation level‐dependent signals in the superior temporal gyrus (STG). Specifically, a classifier trained on the cortical patterns elicited by a set of syllables, which contained two phonemes, could distinguish the cortical patterns elicited by other syllables that contained the two phonemes. The results indicated that phonemes have unique representations in the STG. In addition, there was a categorical effect, i.e. the cortical patterns of consonants were similar, and so were the cortical patterns of vowels. Further analysis showed that phonemes exhibited stronger encoding specificity in the mid‐STG than in the anterior STG.     

The relationship between early speech and later speech and language performance for children with cleft lip and palate

This study examined the relationship between speech measures at presurgery/9 months and postsurgery/13 months and speech and language performance at 21 months for children with cleft lip and palate and their noncleft peers. Comparisons were also made between the speech and lexical development of children with cleft lip and palate and noncleft children at 21 months of age. The participants included 30 children; 15 with cleft lip and palate and 15 noncleft children. Results revealed differences between the groups for several measures of speech and lexical development at 21 months. For the children with cleft palate, correlational analyses suggested that true stop production, both immediately before and after palatal surgery, was positively correlated with a majority of the speech production measures at 21 months. At postsurgery/13 months, true stop production was related to later vocabulary development, and size of true consonant inventory was related to all measure of speech production and one measure of lexical development at 21 months. For the noncleft group, true canonical babbling ratio at 13 months was the only measure that was significantly correlated with any of the speech and/or language measures at 21 months. The impact of clefting on prelinguistic and later speech and language skills is discussed.     

Evaluation of speech errors in Putonghua speakers with cleft palate: A critical review of methodology issues

Speech errors associated with cleft palate are well established for English and several other Indo-European languages. Few articles describing the speech of Putonghua (standard Mandarin Chinese) speakers with cleft palate have been published in English language journals. Although methodological guidelines have been published for the perceptual speech evaluation of individuals with cleft palate, there has been no critical review of methodological issues in studies of Putonghua speakers with cleft palate. A literature search was conducted to identify relevant studies published over the past 30 years in Chinese language journals. Only studies incorporating perceptual analysis of speech were included. Thirty-seven articles which met inclusion criteria were analyzed and coded on a number of methodological variables. Reliability was established by having all variables recoded for all studies. This critical review identified many methodological issues. These design flaws make it difficult to draw reliable conclusions about characteristic speech errors in this group of speakers. Specific recommendations are made to improve the reliability and validity of future studies, as well to facilitate cross-center comparisons.     

The relationship between early speech and later speech and language performance for children with cleft lip and palate

This study examined the relationship between speech measures at presurgery/9 months and postsurgery/13 months and speech and language performance at 21 months for children with cleft lip and palate and their noncleft peers. Comparisons were also made between the speech and lexical development of children with cleft lip and palate and noncleft children at 21 months of age. The participants included 30 children; 15 with cleft lip and palate and 15 noncleft children. Results revealed differences between the groups for several measures of speech and lexical development at 21 months. For the children with cleft palate, correlational analyses suggested that true stop production, both immediately before and after palatal surgery, was positively correlated with a majority of the speech production measures at 21 months. At postsurgery/13 months, true stop production was related to later vocabulary development, and size of true consonant inventory was related to all measure of speech production and one measure of lexical development at 21 months. For the noncleft group, true canonical babbling ratio at 13 months was the only measure that was significantly correlated with any of the speech and/or language measures at 21 months. The impact of clefting on prelinguistic and later speech and language skills is discussed.     

Neural evidence of allophonic perception in children at risk for dyslexia

Learning to read is a complex process that develops normally in the majority of children and requires the mapping of graphemes to their corresponding phonemes. Problems with the mapping process nevertheless occur in about 5% of the population and are typically attributed to poor phonological representations, which are – in turn – attributed to underlying speech processing difficulties. We examined auditory discrimination of speech sounds in 6-year-old beginning readers with a familial risk of dyslexia (n=31) and no such risk (n=30) using the mismatch negativity (MMN). MMNs were recorded for stimuli belonging to either the same phoneme category (acoustic variants of /b?/) or different phoneme categories (/b?/ vs. /d?/). Stimuli from different phoneme categories elicited MMNs in both the control and at-risk children, but the MMN amplitude was clearly lower in the at-risk children. In contrast, the stimuli from the same phoneme category elicited an MMN in only the children at risk for dyslexia. These results show children at risk for dyslexia to be sensitive to acoustic properties that are irrelevant in their language. Our findings thus suggest a possible cause of dyslexia in that they show 6-year-old beginning readers with at least one parent diagnosed with dyslexia to have a neural sensitivity to speech contrasts that are irrelevant in the ambient language. This sensitivity clearly hampers the development of stable phonological representations and thus leads to significant reading impairment later in life.     

Treating control of voicing in apraxia of speech with variable practice

Background: Apraxia of speech (AOS) is generally considered a phonetic‐motoric disorder. As such, it is reasonable to draw on the motor learning literature to develop interventions for improving articulation. The often cited problem of impaired voicing control is used to test the application of a variable practice approach to training skilled movements in AOS. It is predicted that variable practice—practising a behaviour over a range of possible values or contexts—increases accuracy and stability of a trained behaviour.

Aims: The aims of the study were to test the influence of variable practice conditions on acquisition and long‐term maintenance of voiced and voiceless phonemes in words at the phrase/sentence level as well as on generalisation of treatment effects to phonemes of same and different manner. The protocol was tested on two individuals with moderate AOS, one of whom exhibited a concomitant moderate aphasia.

Methods & Procedures: A single subject multiple baseline across‐subjects design was used to examine efficacy of treatment for improving control of voicing for three fricative/affricate phonemes (Participant 1) or three plosive phonemes (Participant 2). The training sets included two voiced phonemes and one voiceless phoneme, each presented in the initial position of 10 different words. This provided a range of voice onset times and a range of phonetic contexts for each target phoneme, thus providing the variable practice. The inclusion of a voiceless phoneme that was produced at a high level of accuracy during baseline was hypothesised to reduce the chance of overgeneralisation from voiced to voiceless phoneme production.

Outcomes & Results: Consistent with predictions, participants demonstrated improved production of trained voiced phonemes and generalisation of treatment effects to untrained phonemes of same manner only. These effects were maintained up to 3 months post‐treatment. Results support training multiple fricatives or plosives in parallel in a variety of phonetic contexts (i.e., variable practice) as well as including a combination of voiced and voiceless phonemes in treatment to ensure maintenance of accurate voiceless phoneme production.

Conclusions: Results from two participants, varying in overall communication impairment severity, provide promising evidence that a variable practice approach to retraining speech behaviours in AOS is effective. Specifically, this approach resulted in long‐term maintenance of treatment effects and generalisation of treatment effects to untrained phonemes within manner class. Just as importantly, it did not result in overgeneralisation of voicing to voiceless phonemes. Further testing is required before recommending general clinical application.     

Effects of regional dialect on oral-nasal balance and nasality perception

While cross-dialectal variations in nasalance have been investigated in previous studies, the influence of regional dialect on listeners’ perceptual ratings of nasality has received limited research attention. This study explored cross-dialectal differences in the production of oral-nasal balance and the perception of nasality, with special emphasis on Inland North (IN) and Midland (M) dialects in the USA. Twenty-six adults representing the IN (n = 15) and M (n = 11) dialects participated in the study. Oral-nasal balance characteristics and nasality perception were compared between dialects using mean nasalance of various speech stimuli, measured via nasometry, and perceptual ratings of nasality of synthetic vowel stimuli, measured using direct magnitude estimation (DME). Despite similar mean nasalance scores between two regional dialects for standardized passage readings and sustained vowels, IN and M groups significantly differed in their perceptual ratings of nasality, with the DMEs of IN listeners being consistently and significantly higher, i.e. more nasal, than those of M listeners. Our findings provide evidence for perceptual variations of nasality that may exist at a dialectal level in addition to cross-linguistic variations in the perception of nasality as reported by Lee et al. (2008). Further research is needed to determine to what extent perceptual variations of nasality exist in other dialects and how these variations manifest in perceptual judgments of hypernasality and its severity ratings.     

Examining the effects of amplification on the nasalance ratios of hearing-impaired children.

Nasalance scores were obtained for hearing-impaired children. Data speech samples obtained with and without personal amplification were compared for differences between gender and chronological age. Statistical comparisons are presented for each amplification condition. Significant differences for nasalance in the aided and unaided conditions were not evident although a high, positive correlation between conditions was reported. Nasalance, age and gender were not positively related. Dispersion of the nasalance scores for the two speech conditions was suggestive of persisting difficulties with velopharyngeal control during speech activities; mean scores revealed objective evidence of hypernasality.