Nasalance Scores for Normal-Speaking Irish Children

Normative nasalance scores in Chilean adults

PURPOSE

The present study is aimed towards determining and comparing normative nasalance scores in Chilean Spanish-speaking adult men and women.

METHODS

40 women (age range 18 to 35, X = 25.79, SD = 5.83) and 36 men (age range 18 to 35, X = 26.45, SD = 4.08) were invited to participate, all of them without any previous speech therapy, neurological pathologies, intellectual deficits, hearing loss, syndromes, or other diagnosed pathologies that could impact speech production.A study of proper velopharyngeal function was performed, using a perceptual resonance evaluation. Nasalance was determined using a model 6450 Nasometer, during the reading of three standardized speech samples in Spanish: a nasal passage (NP), an oronasal passage (ONP), and an oral passage (OP). Also, the nasalance distance was calculated. Genders were compared using Wilcoxon tests for independent samples.

RESULTS

The NP presented the highest percentage of nasalance, with 52.13% (± 4.73), followed by the ONP with 25.38% (± 3.7), and finally the OP, which presented the lowest value of 14.15% (± 5.03). Meanwhile, nasalance distance was 37.98% (± 5.32). Finally, no significant differences were observed when comparing the nasalance between genders (p >0.05).

CONCLUSION

The nasalance values obtained were similar to those observed for other Spanish speakers. Also, male and women showed similar scores. The results of this study are a contribution to the indirect assessment of velopharyngeal function in Chilean adults.

Evaluation of noise excitation as a method for detection of hypernasality

Hypernasality is a disorder where excess nasal resonance is perceived during speech, often as a result of abnormal coupling between the oral and nasal tracts known as velopharyngeal insufficiency (VPI). The most common cause of VPI is a cleft palate, which affects around 1 in 1650 babies, around ⅓ of whom have persistent speech problems after surgery. Current equipment-based assessment methods are invasive and require expert knowledge, and perceptual assessment methods are limited by the availability of expert listeners and differing interpretations of assessment scales. Spectral analysis of hypernasality within the academic community has resulted in potentially useful spectral indicators, but these are highly variable, vowel specific, and not commonly used within clinical practice. Previous works by others have developed noise excitation technologies for the measurement of oral tract transfer functions using resonance measurement devices (RMD). These techniques provide an opportunity to investigate the structural system abnormalities which lead to hypernasality, without the need for invasive measurement equipment. Thus, the work presented in this study adapts these techniques for the detection of hypernasality. These adaptations include augmentation of the hardware and development of the software, so as to be suitable for transfer function measurement at the nostrils rather than the mouth (nRMD). The new method was tested with a single participant trained in hypernasal production, producing 'normal' and hypernasal vowels, and the recordings validated through a listening test by an expert listener and calculation of nasalance values using a nasality microphone. These validation stages indicated the reliability of the captured data, and analysis of the nRMD measurements indicated the presence of a systematic difference in the frequency range 2 to 2.5 kHz between normal and hypernasal speech. Further investigation is warranted to determine the generalisability of these findings across speakers, and to investigate the origins of differences manifesting in the transfer functions between conditions. This will provide new insights into the effects of nasal tract coupling on voice acoustics, which could in turn lead to the development of useful new tools to support clinicians in their work with hypernasality.

Nasalance Scores as a Function of Skeletal Malocclusion of English-Speaking Adults in the North Indian Population

OBJECTIVE

The objective of this study is quantitative assessment of nasalance for skeletal Class I (normative values), Class II, and III malocclusion in the English language for the North Indian population and to compare the normative values with the nasalance scores obtained from individuals with skeletal Class II and III malocclusion and to evaluate the normative values as a function of gender.

MATERIAL AND METHODS

The study was conducted on a total sample of 200 patients with 100, 50, and 50 in group 1 (control group, Skeletal Class I), group 2 (Skeletal Class II), and group 3 (Skeletal Class III), respectively. ANB angle (anteroposterior angle formed by point A, nasion, and point B) measured on lateral cephalogram was used to categorize the patients into 3 groups. The normative nasalance scores were compared for males and females in the control group. The nasalance scores of skeletal Class II and III subjects were compared to the combined normative scores of the control group. The NasalView was used for the objective assessment of nasalance. Oral syllables (/pa/and/pi/), nasal syllables (/ma/and/mi/), and 3 passages (Zoo passage, Rainbow passage, and Nasal sentences) were used to determine the nasalance scores.

RESULTS

The intragroup comparison of nasalance scores in group 1 showed statistically significant differences for different stimuli. The gender-related comparison showed no statistically significant differences in nasalance scores. The intergroup comparison of nasalance scores for skeletal malocclusion showed no statistically significant differences for different stimuli except statistically significant lower nasalance values for nasal sentences in group 3 compared to the control group.

CONCLUSION

The study concluded that the nasalance scores for nasal sentences in skeletal Class III malocclusion were significantly lower than in the control group and were not statistically significant between the 3 groups for all other stimuli.

Nasalance Scores for Normal Speakers of American English Obtained by the Nasometer II Using the MacKay-Kummer SNAP-R Test

OBJECTIVE

To establish nasalance score norms for adolescent and young adult native speakers of American English and also determine age-group and gender differences using the Simplified Nasometric Assessment Procedures (SNAP) Test-R and Nasometer II.

DESIGN

Prospective study using a randomly selected sample of participants.

SETTING

Greater Cincinnati area and Miami University of Ohio.

PARTICIPANTS

Participants had a history of normal speech and language development and no history of speech therapy. Participants in the adolescent group were recruited from schools in West Clermont and Hamilton County, whereas the young adults were recruited from Miami University of Ohio. The participants of both groups were residents of Cincinnati, Ohio or Oxford, Ohio and spoke midland American English dialect.

OUTCOME MEASURES

Mean nasalance scores for the SNAP Test-R.

RESULTS

Normative nasalance scores were obtained for the Syllable Repetition/Prolonged Sounds, Picture-Cued, and Paragraph subtests. Results showed statistically significant nasalance score differences between adolescents and young adults in the Syllable Repetition, Picture-Cued, and Paragraph subtests, and between males and females in the Syllable Repetition and the Sound-Prolonged subtests. A significant univariate effect was found for the syllables and sentences containing nasal consonants and high vowels compared to syllables and sentences containing oral consonants and low vowels. Across all the SNAP Test-R subtests, the females' nasalance scores were higher than the males. A significant univariate effect was also found across nasal syllables, and high vowels such that the females' nasalance scores were higher than the males. Tables of normative data are provided that may be useful for clinical purposes.

CONCLUSION

Norms obtained demonstrated nasalance score differences according to age and gender, particularly in the Syllable Repetition/Prolonged Sound subtest. These differences were discussed in light of potential reasons for their existence and implications for understanding velopharyngeal function. In addition, nasalance scores are affected by the vowel type and place of articulation of the consonant. These facts should be considered when nasometry is used clinically and for research purposes.

Normative Nasalance Values in Vietnamese With Southern Dialect: Vowel and Tone Effects

Purpose The purpose of the current study was to examine normative nasalance values in Vietnamese adult speakers with Southern dialect and to investigate the effects of vowels and tones on nasalance. Previous studies examining nasalance have been mainly conducted with Indo-European languages. Limited information on nasalance is available in tone languages other than Chinese. Furthermore, tone and vowel effects on nasalance scores in tone languages have not been fully examined. Method Nasalance scores of various speech stimuli including passages, syllables, and prolonged vowels were obtained from Vietnamese-speaking adults with Southern dialect (M _age = 23 years) using a nasometer (KayPENTAX 6450). Results The average nasalance scores of Southern Vietnamese adult speakers were 24.16%, 38.17%, and 70.03% for the oral, oral-nasal, and nasal passages, respectively. Southern Vietnamese speakers produced the highest nasalance scores on the vowel /a/, followed by /i/ and /u/. Nasalance scores of stimuli produced with the falling and restricted tone were significantly lower than those produced with the other tones. Conclusions The normative nasalance values of the current study will contribute as a reference index for the Vietnamese language. The effects of vowels and tones can also provide insight into the development of nasalance testing stimuli and for characterizing nasalance values across languages.

Normative nasalance scores in Tamil-speaking Indian children

OBJECTIVE

The aim of this study was to obtain normative nasalance scores for Indian Tamil-speaking children.

METHODS

Mean nasalance scores were obtained from 175 consecutive Tamil-speaking normal children (95 males, 80 females) aged 5-16 years during the repetition of six standardized sentences: two oral, two oronasal, and two nasal sentences. The nasal view was used to obtain nasalance scores for the standardized sentences.

RESULTS

Group mean and standard deviation (SD) nasalance scores of children for oral, oronasal, and nasal sentence were 35.65(SD 7.20), 44.42(SD 7.37), and 57.21(SD 8.15), respectively. The mean nasalance values of children aged 9-12 years were greater than children aged 5-8 years and 13-16 years for nasal sentences (p < .001). Males were found to have significantly higher nasalance scores for oral and oronasal sentences (p < .05) although these differences were within the range of normal variation.

CONCLUSIONS

The present study provides normative nasalance scores for Tamil-speaking Indian children.

English Nasalance Values of Chinese Learners of English

<b><i>Introduction:</i></b> Although a number of studies have been conducted to investigate nasalance scores of speakers of different languages, little research has examined the nasalance characteristics of second language learners. <b><i>Objective:</i></b> The goal of the current study was to examine whether English nasalance values of Mandarin Chinese speakers are similar to those of native English speakers, examining the potential effect of the first language on the nasalance scores of the second language production. <b><i>Methods:</i></b> Thirty-two adults (16 Mandarin Chinese speakers and 16 native English speakers) with a normal velopharyngeal anatomy participated. Nasalance scores of various speech stimuli were obtained using a nasometer and compared between the 2 groups. <b><i>Results and Conclusions:</i></b> Chinese learners of English produced higher nasalance scores than native English speakers on prolonged vowel /i/ and /a/, the syllable “nin,” and non-nasal sentences and passages. The first language effect on nasalance of the second language found in the current study suggests the importance of linguistic consideration in the clinical evaluation of resonance.

Measurement of Nasalance Scores Without Touching the Philtrum for Better Comfort During Speech Assessment and Therapy: A Preliminary Study

OBJECTIVE

The Kay Pentax nasometer uses a separator plate that touches the philtrum of a patient to separate the nasal and oral sound energies for nasalance measurement. However, the separator plate can restrict the natural movement of the patient's upper lip and generate unpleasant pressure on the patient's philtrum. The present study was intended to measure nasalance scores without touching the philtrum for better comfort during speech assessment and therapy.

METHODS

Nasalance scores of 10 males and 10 females having no speech disorders were measured under 4 levels (0, 5, 10, and 15 mm) of the gap between the plate and the philtrum (denoted as plate-to-philtrum gap) using Nasometer II 6450 for nasal (Nasal Sentences) and oral (Zoo Passage) stimuli. Regression formulas were established to examine the relationships between nasalance score and plate-to-philtrum gap for the stimuli. To provide nasalance scores equivalent to those measured for the contact condition, compensation factors for the 5 mm plate-to-philtrum gap measurement condition were identified for the stimuli.

RESULTS

The nasalance scores were significantly different between the 4 different plate-to-philtrum gaps for the stimuli. Compensation factors for the Nasal Sentences and the Zoo Passage were identified as 1.17 and 0.71, respectively.

CONCLUSIONS

The 5 mm plate-to-philtrum gap condition after multiplying the compensation factors can provide equivalent nasalance scores to the conventional contact measurement condition which may provide better comfort in speech assessment and therapy.

Speech stimuli and nasalance scores for the assessment of resonance in in Mandarin speaking Malaysian children

This study was designed to develop language-specific stimuli for the assessment of resonance and to obtain nasalance scores using the newly developed speech stimuli in Mandarin. Gender and age influences on nasalance scores for each of the stimulus were also examined. Participants recruited were typically developing Mandarin-speaking ethnic Chinese children aged 6;00-7;11 growing up in Malaysia. Perceptual ratings of nasality were made based on the GOS.SP.ASS.'98 (revised) for children while nasalance scores were recorded for each stimulus using the Nasometer II (Model 6400). Fifty Mandarin-speaking children (24 males and 26 females) were recruited. None of the participants were perceived with abnormal nasality on the three stimuli. The mean nasalance scores for the Mandarin stimuli were 16.08% (SD = 2.57, 95% CI = 15.35-16.81) for the Oral passage, 25.20% (SD = 3.63, 95% CI = 24.17-26.23) for the Oral-Nasal passage and 55.44% (SD = 4.17, 95% CI = 54.25-56.63) for the Nasal passage. No significant age- and gender-related differences were observed for all the three stimuli. This is the first set of Mandarin stimuli and nasalance norms for Mandarin-speaking children in Malaysia. The influence of phonetic content on nasalance is supported. Findings call for language-specific normative nasalance data and careful selection of stimuli for the assessment of resonance.

Nasometric evaluation of resonance disorders: A norm study In Turkish

OBJECTIVE

The aim of this study was to adapt the Simplified Nasometric Assessment Procedures-Revised (SNAP-R) [1] to Turkish, gather norms from Turkish speakers, and test the sensitivity and specificity of the adapted test. Finally, this study was designed to determine if there are any differences in average nasalance scores due to age, gender, and vowel content of the passage.

METHODS

240 children without any known speech, language or hearing disorders and 40 children with cleft palate participated in the study. Participants were divided into three groups according to their age (ages 4-7; 8-12; and 13-18). Data for this descriptive study was collected in the school settings and in a center of speech and language therapy.

RESULTS

This study showed a slight increase in nasalance with age, but no difference in nasalance based on gender. Furthermore, the nasalance score is determined by vowel content of the passage and that high vowels have higher nasalance than the low vowels.

CONCLUSION

This paper offers a new test for nasometric evaluation in the Turkish language, which has relatively high specificity and sensitivity in the evaluation of hypernasality.

The Use of the Nasometer and Interpretation of Nasalance Scores

Purpose

The acoustic characteristics of oral–nasal coupling (nasalization) have clinical implications for speech-language pathologists because excessive oral–nasal coupling results in a resonance disorder referred to as hypernasality . Nasometry is a tool that allows clinicians to measure the effect of oral–nasal coupling in the clinical setting. This clinical focus article summarizes the large volume of research on nasometry and clarifies its clinical application.

Conclusion

Although the precise relationship between the acoustics of oral–nasal coupling and the perception of hypernasality remains unclear, measuring the acoustic effects of oral–nasal coupling is useful in the evaluation and treatment of resonance disorders.

Normative data on nasalance scores for Farsi speaking children: Influence of age, gender and phonetic context

BACKGROUND

Normative nasalance scores are essential for treatment and assessment purposes for clinicians. The purpose of the current study is to determine the normative data on nasalance scores for Farsi speaking children. Comparing to the obtained normative data, hypernasal or hyponasal speech (i.e. the higher or lower nasalance score) can be evaluated.

METHODS

Ninety-six Farsi speakers ranging from 4 years to 11 years old with typically developing speech were included in this study. Mean nasalance scores were obtained using the Universal Parameters System sentences with nasometer II (model 6450). The nasalance data was also analyzed for any gender, age and phonetic context dependence.

RESULTS

Normative nasalance values were determined, Nno differences were found for gender and age for the school-aged children. With an increasing in age, the nasalance score also increased in oral passages but not in nasal passages. Furthermore, amongst the nasalance scores there was a significant difference between these four categories of sentences: 7 sentences loaded with oral stop consonants, 5 sentences loaded with oral fricative consonants, 2 sentences loaded with oral affricatives and 3 sentences loaded with nasal consonants.

CONCLUSIONS

The absence of age and gender differences led to a computation of an overall mean nasalance score for different types of phonetic context (Nasal, oral and oronasal). These normative nasalance data for Farsi speaking children will provide important reference information during speech assessments of children with velopharyngeal insufficiency.

Effects of Knowledge of Task on Control of Oral-Nasal Balance in Speech

<b><i>Introduction:</i></b> Previous research has shown that altering the nasal signal level auditory feedback changed the control of oral-nasal balance in normal speakers. The present study investigated whether knowledge of the task and the instruction not to compensate would change the participants’ response to the manipulation. <b><i>Methods:</i></b> Twenty participants (10 females) in 2 groups continuously repeated a sentence while their nasal signal level was increased or decreased and fed back to them via headphones, so the speakers heard themselves as more or less nasal, respectively. After the first recording session, participants were debriefed about the true nature of the experiment. They were instructed not to compensate in the second recording session. The outcome measures were the percentage changes of nasalance scores from the first baseline. <b><i>Results:</i></b> Statistical analysis using a repeated measures analysis of variance showed an effect of the nasal signal level, <i>F</i>(5,80) = 2.51, <i>p</i> = 0.049, and a nasal signal level by knowledge of task interaction effect, <i>F</i>(5,80) = 3.25, <i>p</i> = 0.019. Post hoc tests showed that the maximum nasal signal level auditory feedback resulted in a significant decrease of nasality from the initial baseline. <b><i>Conclusion:</i></b> Despite knowledge of the task, speakers were unable to resist compensating. As found in previous research, there was a numerically higher compensation response at the maximum than at the minimum nasal signal level auditory feedback condition.

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.

Normative nasalance scores for Estonian children

Normative nasalance scores are essential for the treatment and assessment purposes for clinicians. Till date, no studies have been done on nasalance in Estonia. This research was conducted to develop Estonia-specific optimized speech stimuli for Nasometer II and establish the normative nasalance scores. Ninety-two randomly selected healthy and 14 cleft palate Estonian monolingual children, aged four to seven years, were included as participants. Estonian language-specific test material was developed. The Estonian test material consisted of 24 speech stimuli. Based on the phoneme content, the stimuli were divided into three groups: (1) sentences that included oral and nasal phonemes and targeted the same phoneme distribution as in spontaneous speech, (2) sentences that included only oral phonemes and (3) sentences that were loaded with nasal phonemes. Nasometer II software was used to calculate the nasalance scores for each child and each sentence. Results indicated that there were significant differences in nasalance scores for oronasal and oral stimuli scores, and no significant differences were found in nasal stimuli scores between the study and control group. The threshold for oronasal stimuli was 42.1-18.9, oral stimuli was 27.9-3.9 and nasal stimuli was 69.4-46.2. In conclusion, Estonia-specific optimized speech stimuli were developed and normative nasalance scores were established. These normative scores can be used for the diagnosis and follow-up treatment of patients with resonance disorders, especially for patients with cleft palate.

Nasometric Comparison Between Spanish–English Bilingual and English Monolingual Children

Objective:

It is well established in the literature that English diagnostic tests should not be directly applied to speakers whose primary language is Spanish. Normative nasalance data across word and sentence-level stimuli among Spanish–English bilingual children living in the United States have not been provided. The present study aims to (1) compare differences in nasalance between typically developing Spanish–English bilingual children and English-speaking monolingual children and (2) determine whether within-speaker nasalance differences exist in Spanish–English bilingual children when presented with English and Spanish speech stimuli.

Design:

Thirty-four typically developing children including 17 monolingual English speakers and 17 Spanish–English bilingual speakers with normal velopharyngeal anatomy between 5 and 7 years of age participated in the study. Speakers were recorded using a nasometer producing sets of stimulus items at the word and sentence level in English (English monolinguals) and in both Spanish and English for bilingual children.

Results:

Results indicated no statistically significant difference between nasalance values across the different stimuli between monolingual and bilingual participants. However, within-subject effects showed statistical significance between English and Spanish word stimuli among the bilingual group.

Conclusions:

These findings emphasize the importance of using language-specific diagnostic materials for nasalance testing, which would be of importance in the treatment of individuals with cleft palate.

The Cleft Audit Protocol for Speech—Augmented: A Validated and Reliable Measure for Auditing Cleft Speech

Objectives

To develop an assessment tool for use in intercenter audit studies of cleft speech and to test its acceptability, validity, and reliability. The tool is to be used systematically to record and report speech outcomes, providing an indication of treatment needs and continuing burden of care.

Setting

Regional Cleft Center, U.K.

Methods

The Cleft Audit Protocol for Speech—Augmented (CAPS-A) was developed by three cleft speech experts who identified the key features required from existing assessment measures. Criterion validity was assessed by comparing the Cleft Audit Protocol for Speech—Augmented outcomes reported for 20 cases with clinical assessment results and other investigations. Intra- and interrater reliability were tested following the training of specialist speech and language therapists who used the Cleft Audit Protocol for Speech—Augmented on two occasions to assess 10 cases. The raters evaluated acceptability and ease of using a questionnaire.

Results

The mean percentage agreement for criterion validity in each section was 87% (range 70% to 100%). Both intra- and interexaminer reliability were rated as good/very good (Kappa 0.61 to 1.00) for seven sections and moderate (Kappa 0.41 to 0.60) for three sections. Raters reported that the Cleft Audit Protocol for Speech—Augmented was acceptable and easy to use with appropriate training.

Conclusion

An acceptable, valid, and reliable cleft speech audit tool has been developed based on a small sample. The Cleft Audit Protocol for Speech—Augmented is recommended for use in intercenter audit studies in the U.K. and Ireland and could be used in other English-speaking countries. In addition, it has wider applicability for use in reporting speech outcomes of surgical procedures.

Validity of test stimuli for nasalance measurement in speakers of Jordanian Arabic

OBJECTIVE

The objective of the study was to establish the validity of passages for measuring nasalance of Jordanian speakers of Arabic.

DESIGN

Two Arabic text passages were constructed; the Spring Passage is devoid of nasal consonants and the Home Passage contains both oral and nasal consonants. Nasalance was measured for participants while reciting each passage three times. Perceptual ratings of hypernasality were also obtained for each participant on each passage using a 5-point equal-appearing rating scale.

PARTICIPANTS

Forty-seven children and adults ranging in age between 9 and 26 years participated in the study. Twenty-three participants had no history of communication disorders, and 24 had repaired cleft palate.

RESULTS

Correlation coefficient between ratings of hypernasality and the nasalance scores was significant for the Spring Passage (r = 0.88, p > 0.001) and for the Home Passage (r = 0.78, p > .001). Using cutoff scores of 17% and 36% of nasalance for the Spring and the Home Passages, respectively, and a threshold score of 1.5 for hypernasality, sensitivity for the Spring Passage was 88% and the Home Passage was 78%.

CONCLUSIONS

Results showed the validity of the Spring Passage and the Home Passage in measuring nasalance scores as proved by their high sensitivity and strong correlation with perceptual rating of hypernasality.

Prosthodontic Rehabilitation of Arabic Speaking Individuals with Velopharyngeal Incompetence: A Preliminary Study

Background:

Hypernasality is a frequently encountered problem in the speech of individuals with velopharyngeal incompetence. The use of palatal lift appliance (PLA) is the main treatment option for correction of velopharyngeal incompetence. The literature on the outcomes of using prosthetics treatment for Arabic speaking patients is scarce.

Objective:

The aim of this study was to investigate the effect of using PLA on hypernasality of Arabic speaking patients with velopharyngeal incompetence.

Methods:

Six participants with age ranging from 9 to 61 years (4 males and 2 females) were recruited between October 2013 and August 2014. Written informed consents were taken from all the adult participants/the guardians of under-aged participants. All patients exhibited hypernasality with different etiologies for velopharyngeal incompetence (head injury, cerebrovascular accident, and neurological disorders). They were treated with PLAs which were constructed to elevate the dysfunctional soft palate. Nasalance scores and perceptual speech acceptability ratings were measured/evaluated in both situations; with and without appliances. Paired t-test was used to analyze the perceptual ratings and nasalance scores in order to detect any significant change in hypernasality pre and post insertion of PLA.

Results:

There was a statistically significant decrease (p>0.05) in nasalance scores (Pa, Pi, Ma, Mi, a, i) after PLA insertion. The subtest /u/ showed insignificant change (p= 0.056). Perceptual ratings showed significant reduction in hypernasality which was consistent with nasalance measurements.

Conclusion:

PLAs can reduce hypernasality in Arabic speaking patients who suffer from velopharyngeal impairment.

Escores de nasalância de falantes do Português Brasileiro aos cinco anos de idade

RESUMO Objetivo Determinar valores de nasalância de crianças falantes do Português Brasileiro sem alterações na produção da fala, atraso de linguagem e deformidades dentofaciais evidentes, aos 5 anos de idade, e verificar as diferenças entre tipos de emissão e entre gêneros. Método A nasalância foi determinada em 20 crianças, 11 do gênero masculino e idade entre 4 anos e 10 meses e 5 anos e 11 meses, utilizando um nasômetro II 6450 (KayPENTAX), na produção de oito sílabas tipo consoante-vogal e uma sequência de nove vocábulos. A significância das diferenças entre os tipos de emissões foi verificada pelo Teste de Tukey e, entre os gêneros, pelo teste de Mann-Whitney, para um nível de 5%. Resultados Os valores médios de nasalância foram os seguintes: /pa/= 10±4%, /pi/= 22±7%, /sa/= 11±5%, /si/= 24±11%, /ma/= 57±11%, /mi/= 73±13%, /la/= 14±9%, /li/= 25±11%, vocábulos (pipa, bis, burro, tatu, pilha, cuca, gui, fila, luz)= 20±6%. Na maioria das comparações, os valores de nasalância das sílabas nasais foram significantemente maiores do que os das sílabas orais (com vogal alta ou neutra) e os valores das sílabas orais com vogal alta foram significativamente maiores que os das sílabas orais com vogal neutra. Não houve diferença significante entre os gêneros. Conclusão Foram definidos valores normais de nasalância de crianças falantes do Português Brasileiro, de 5 anos de idade, sendo que a metodologia empregada pode servir de padrão para o diagnóstico precoce de desvios de nasalidade, como a hipernasalidade observada na fala de crianças com fissura palatina.

Influence of gender and age on the Nasality Severity Index 2.0 in Dutch-speaking Flemish children and adults

This study aimed to explore the influence of gender and age on the Nasality Severity Index 2.0 (NSI 2.0), an instrumental multiparametric index to determine hypernasality. Additionally, reference values will be established for this new index. Influence of gender and age on the NSI 2.0 was explored in 80 Flemish-speaking children (4-12 years; 40 boys, 40 girls) and 60 Flemish-speaking adults (18-60 years, 30 men, 30 women) without resonance disorders by determining its incorporated acoustic parameters: nasalance of the vowel/u/and an oral text, determined by a Nasometer, and voice low tone to high tone ratio (VLHR) of the vowel/i/. The equation yields NSI 2.0 = 13.20 - (0.0824 × nasalance/u/(%)) - (0.26 × nasalance oral text (%)) - (0.242 × VLHR/i/4.47*F0 Hz (dB)). No effect of gender or age was found on the NSI 2.0 in children. However, significant differences were found for the NSI 2.0, nasalance of/u/and an oral text between adult men and women. Additionally, an interaction effect between gender and age was found for these parameters. Consequently, separate reference values for the NSI 2.0 in children, adult men and adult women were established. Based on these reference scores, deviation of the NSI 2.0 score in patients with resonance disorders can be defined, which can determine the need for (additional) intervention. Further research can explore the possible influence of language on the index.

Bulbar dysfunction in normal pressure hydrocephalus: a prospective study

OBJECTIVE Normal pressure hydrocephalus (NPH) is clinically characterized by gait disturbance, cognitive impairment, and urinary incontinence, as well as enlargement of the ventricles. To the best of the authors' knowledge, there have been no previous publications regarding the correlation between bulbar dysfunction and NPH. The primary objective of this study was to compare preoperative and postoperative prevalence of bulbar dysfunction in patients with NPH. Secondary objectives included assessing the results of surgery for swallowing, speech, gait, cognition, and urination, and evaluating the correlation between bulbar dysfunction and triad symptoms. METHODS Fifty-three patients with NPH who underwent shunt placement surgery at Siriraj Hospital were included in the study. Patients were evaluated for gait, cognition, urination, swallowing, and speech before and 6 months after shunt placement. Triad symptoms were assessed using standard methods. Bulbar dysfunctions were assessed using the Swallowing Problem Questionnaire, Thai Articulation Test, Resonation Screening Test (RST), and Thai Nasality Test. The Thai Speech Assessment Program and nasometer were used for objective speech measurement. RESULTS Preoperatively, 86% (43/50) of patients had swallowing problems and 75% (37/49) had speech problems, as measured by the RST. Postoperatively, there was significant improvement in swallowing (p < 0.001), speech problems by RST (p = 0.008), and voice volume (p = 0.009), but no significant change in the nasometer test. All triad symptoms were improved. There were significant correlations between swallowing impairment and gait disturbance (r = 0.358, p = 0.009), and RST and cognitive impairment (r = -0.502, p < 0.001). CONCLUSIONS This is the first study of bulbar dysfunction in patients with NPH. The results showed that the prevalence of bulbar dysfunction is very high. The correlation between bulbar dysfunction and the classic NPH triad has been documented and published. These bulbar symptoms also significantly improved after surgery. As such, bulbar dysfunction should be regarded as a core symptom that should be considered along with the classic triad in the clinical diagnosis and management of NPH.

Quantitative Endoscopic Phototransducer Investigation of Normal Velopharyngeal Physiology

PURPOSE

The purpose of this research was to learn the extent to which healthy individuals vary in their ability to achieve velopharyngeal closure for speech.

METHOD

Twenty healthy adult volunteers (10 women, 10 men) were tested using an endoscopic phototransducer system that tracks variations in velopharyngeal closure during speech production. Each speaker produced multiple repetitions of three utterances that differed in phonetic content. The data were amplitude normalized and averaged for each speaker.

RESULTS

Average phototransducer measurements were similar across subjects for utterances containing only oral phonemes. Average percentage of velopharyngeal closure varied considerably among subjects when producing utterances containing both oral and nasal phonemes (54%-95%). Average percentage of velopharyngeal closure levels were significantly lower (p < .05) for utterances that included nasal consonants.

CONCLUSIONS

Phototransducer measurements of velopharyngeal closure for speech are sensitive to nasal phoneme content. The findings suggest that motor programming that accomplishes rapid oral-nasal velopharyngeal valving for speech may differ among healthy subjects. However, such variations in motor programming may not perceptually affect typical speakers. If present in individuals with abnormal velopharyngeal mechanisms, these variations may help explain variations among speakers in speech outcomes after physical and behavioral management.

Short-term and long-term test-retest reliability of the Nasality Severity Index 2.0

PURPOSE

The Nasality Severity Index 2.0 (NSI 2.0) forms a new, multiparametric approach in the assessment of hypernasality. To enable clinical implementation of this index, the short- and long-term test-retest reliability of this index was explored.

METHODS

In 40 normal-speaking adults (mean age 32y, SD 11, 18-56y) and 29 normal-speaking children (mean age 8y, SD 2, 4-12y), the acoustic parameters included in the NSI 2.0 (i.e. nasalance of the vowel /u/ and an oral text, and the voice low tone to high tone ratio (VLHR) of the vowel /i/) were obtained twice at the same test moment and during a second assessment two weeks later. After determination of the NSI 2.0, a comprehensive set of statistical measures was applied to determine its reliability.

RESULTS

Long-term variability of the NSI 2.0 and its parameters was slightly higher compared to the short-term variability, both in adults and in children. Overall, a difference of 2.82 for adults and 2.68 for children between the results of two consecutive measurements can be interpreted as a genuine change. With an ICC of 0.84 in adults and 0.77 in children, the NSI 2.0 additionally shows an excellent relative consistency. No statistically significant difference was withheld in the reliability of test-retest measurements between adults and children.

CONCLUSION

Reliable test-retest measurements of the NSI 2.0 can be performed. Consequently, the NSI 2.0 can be applied in clinical practice, in which successive NSI 2.0 scores can be reliably compared and interpreted.

LEARNING OUTCOMES

The reader will be able to describe and discuss both the short-term and long-term test-retest reliability of the Nasality Severity Index 2.0, a new multiparametric approach to hypernasality, and its parameters. Based on this information, the NSI 2.0 can be applied in clinical practice, in which successive NSI 2.0 scores, e.g. before and after surgery or speech therapy, can be compared and interpreted.

Speech nasality and nasometry in cleft lip and palate

INTRODUCTION

Perceptual evaluation is considered the gold standard to evaluate speech nasality. Several procedures are used to collect and analyze perceptual data, which makes it susceptible to errors. Therefore, there has been an increasing desire to find methods that can improve the assessment.

OBJECTIVE

To describe and compare the results of speech nasality obtained by assessments of live speech, the Test of Hypernasality (THYPER), assessments of audio recorded speech, and nasometry.

METHODS

A retrospective study consisting of 331 patients with operated unilateral cleft lip and palate. Speech nasality was assessed by four methods of assessment: live perceptual judgement, THYPER, audio-recorded speech sample judgement by multiple judges, and nasometry. All data were collected from medical records of patients, with the exception of the speech sample recording assessment, which was carried out by multiple judges.

RESULTS

The results showed that the highest percentages of absence of hypernasality were obtained from judgements performed live and from the THYPER, with equal results between them (79%). Lower percentages were obtained from the recordings by judges (66%) and from nasometry (57%).

CONCLUSION

The best results among the four speech nasality evaluation methods were obtained for the ones performed live (live nasality judgement by a speech pathologist and THYPER).

Nasalance scores for normal Korean-speaking adults and children: Effects of age, vowel context, and stimulus length

OBJECTIVES

The purpose of this study was to collect nasalance scores for normal Korean-speaking children and adults and to determine whether age, vowel contexts, and stimulus length influence nasalance scores.

METHODS

Fifty-seven children aged 4-6 years and 17 adults participated in the study. Mean nasalance scores were obtained for eight sentences devoid of nasal consonants divided into the vowel/a/and/i/contexts; the sentences consisted of 4, 8, 16, and 31 syllables. All subjects were asked to repeat the speech stimuli twice after the examiner. The headset of the nasometer was replaced between the first and second recordings. An average value of the nasalance scores from the two recordings for each stimulus was calculated and used in the statistical analysis as a representative measure for each subject.

RESULTS

Mean and standard deviations of nasalance scores were obtained for each speech stimulus and each age group. The statistical analysis indicated significant effects of age and vowel context and a significant interaction between age and the vowel context on nasalance scores. However, the effect of stimulus length on nasalance scores was not significant. All speakers had higher nasalance scores for the vowel/i/contexts than for the vowel/a/contexts. Adults had higher nasalance scores compared to children in both vowel contexts.

CONCLUSIONS

These normal nasalance values from Korean-speaking children aged 4-6 years will provide important reference information for resonance assessment of children with cleft palate who have been considered for secondary palatal surgery. The results of the study suggest that subjects' age and the vowel content of speech stimuli should be carefully considered when interpreting the nasalance scores.

Dialectical effects on nasalance: a multicenter, cross-continental study

PURPOSE

This study investigated nasalance in speakers from six different dialectal regions across North America using recent versions of the Nasometer. It was hypothesized that many of the sound changes observed in regional dialects of North American English would have a significant impact on measures of nasalance.

METHOD

Samples of the Zoo Passage, the Rainbow Passage, and the Nasal Sentences were collected from young adult male and female speakers (N=300) from six North American dialectical regions (Midland/Mid-Atlantic; Inland North Canada; Inland North; North Central; South; and Western dialects).

RESULTS

Across the three passage types, effect sizes for dialect were moderate in strength and accounted for approximately 7%-9% of the variation in nasalance. Increased differences in nasalance tended to occur between speakers from distinctly different geographical regions, with the highest nasalance across all passages observed for speakers from the Texas South dialect region.

CONCLUSION

Clinicians and researchers who use perceptual and instrumental measures of speech production should be aware that dialectical and socially acquired speech patterns may influence the acoustic characteristics of speech and may also influence the interpretation of normative expectations and typical versus disordered cutoff scores for instruments such as the Nasometer.

Nasalance scores for normal Korean-speaking adults and children

There are numerous nasometric studies to date, including normative nasalance scores for various languages as well as nasometric differences in age, gender, race and region except the Korean language. In this regard, we sought to establish normative nasalance scores for Koreans. We created speech samples based on the everyday use of phonemes in the Korean language which were syntactically simple for children. In addition, we analysed nasometric features based on age and gender and confirmed test-retest reliability. The study included 108 children (54 girls and 54 boys, aged 7-11 years) and 108 adults (54 women and 54 men, aged 18-29 years) with normal articulation, resonance, voice and hearing. Nasometer II 6400 was used to measure the nasalance scores. The subjects read or repeated three speech stimuli, each consisting of 33, 36 and 24 syllables: (1) an oral passage devoid of nasal consonants, (2) an oro-nasal passage and (3) nasal sentences. For each stimulus, mean nasalance scores were obtained and gender or age dependence was analysed, using two-way analyses of variance. The mean nasalance scores for the oral passage, oro-nasal passage and nasal sentences were 11.69% (standard deviation (SD) 3.68), 34.04% (SD 4.88) and 63.72% (SD 6.07), respectively. Female speakers exhibited significantly higher nasalance scores than male speakers on the oro-nasal passage (p = 0.000) and nasal sentences (p = 0.004). Children exhibited significantly higher nasalance scores than adults on nasal sentences (p = 0.000). The nasalance scores in children and females were a little higher. Korean normative data will provide reference information in the evaluation and treatment of resonance problems.

Comparison between perceptual assessments of nasality and nasalance scores

BACKGROUND

There are different reports of the usefulness of the Nasometer™ as a complement to listening, often as correlation calculations between listening and nasalance measurements. Differences between findings have been attributed to listener experience and types of speech stimuli.

AIMS

To compare nasalance scores from the Nasometer with perceptual assessments, for the same and different Swedish speech stimuli, using three groups of listeners with differing levels of experience in judging speech nasality.

METHODS & PROCEDURES

To compare nasalance scores and blinded listener ratings of randomized recordings using three groups of listeners and two groups of speakers. Speakers were either classified as having hypernasal speech or speech with typical speech resonance. Listeners were speech-language pathologists (SLPs) working predominantly with resonance disorders, other SLPs and untrained listeners.

OUTCOMES & RESULTS

Correlations (r(s)) between hypernasality ratings and nasalance scores for each listener group and speech stimuli were calculated. For both groups of SLPs all correlations between perceptual ratings and nasalance scores were significant at p= 0.01. The correlations between the nasalance scores and ratings by listeners in the SLP groups were higher than those for the untrained listener group regardless of stimulus type. Post-hoc Mann-Whitney U-tests showed that the only difference that was significant was expert SLP group versus untrained listener group. Secondly, correlations between perceptual ratings and oral stimulus nasalance scores were higher when the perceptual ratings were based on spontaneous speech rather than on the oral stimulus. However, a Wilcoxon signed rank test showed that the difference was not significant. A third finding was that correlations between oral stimulus nasalance scores and perceptual scores were higher than those between mixed stimulus nasalance scores and perceptual scores. A Wilcoxon signed rank test showed that the difference was significant.

CONCLUSIONS & IMPLICATIONS

The Nasometer might be useful for the SLP with limited experience in assessing resonance disorders in differentiating between hyper- and hyponasality. With listener reliability for ratings of hypernasality still being an issue, the use of a nasalance score as a complement to the perceptual evaluation will also aid the expert SLP. It will give an alternative way of quantifying speech resonance and might help in especially hard to judge cases.

Nasalance scores for typical Irish English-speaking adults

The aim was to establish normative nasalance values for Irish English-speaking adults. Thirty men and 30 women with normal resonance read aloud 16 sentences from the Irish nasality assessment protocol, the Zoo passage, and the Rainbow passage. The speech samples were recorded using the Nasometer II 6400. Results of a mixed between-within subjects ANOVA indicated no significant gender effect on nasalance scores. The speakers showed significantly higher nasalance scores for high-pressure consonant sentences than low-pressure consonant sentences, and for the Rainbow passage than total test sentences. There was no significant difference between high-pressure consonant sentences and the Zoo passage. Compared to previous studies, the Irish young adults had lower nasalance scores than Irish children and than young adults with North American dialects.

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.

Nasality evaluation of Turkish phonemes in vowel-consonant combinations

OBJECTIVES

The purpose of this study is to find average nasalance values of Turkish syllables with the nasometer.

METHODS

This study is done at Hacettepe University Department of Otolaryngology Audiology and Speech Pathology Unit with 50 participating children.

RESULTS

The normative nasalance values of Turkish phonemes are determined. It is found that nasalance scores of syllables that is combined with/i/phoneme is statistically have higher nasalance scores than/a/and/e/phonemes (p<0.05). There is no difference find statistically between age and nasalance value (p>0.05). Statistical difference between age and nasalance score is found in "iki, şe, eşe, işi, aç, eç, çi, içi, iç, al, yi, iy, iyi, yiy, ana, ne" syllables (p<0.05). These phonemes have positive relation with the age. There is no statistical difference between sex and nasalance scores (p<0.05). Statistical difference is only found in "tat- te- li- lil- aya" syllables (p<0.05). On these phonemes it is found that girls have higher nasalance score than boys.

CONCLUSION

As a result, it is thought that gathered nasalance values of Turkish phonemes will be useful for resonance disorder diagnosis and follow ups on treatment.

Nasometry cooperation in children 4-6 years of age

OBJECTIVE

Hypernasality is a common problem in cleft care. It should be treated before the age of six, because of the impact it can have on speech sound development in young children. An objective method of nasalance evaluation is nasometry. Cooperation of young children, by nature, differs over time and situations. First aim of this study is to indicate a minimum age for cooperation with the nasometer. Second aim is to compare the cooperation of children in the most used research setting (school) with the cooperation of children in the most used setting in daily practice (ENT outpatient clinic).

METHOD

Children from four to six years of age were recruited from schools. Outpatient clinic children were recruited from the Groningen ENT clinic. Both groups were tested with the nasometer. The cooperation with installation and repetition of speech stimuli were noted.

RESULTS

118 school children and 41 outpatient clinic children were recruited. Six years old children cooperated significantly better than the five years old. The five years old cooperated better than the four years old. Moreover, school children cooperated significantly better than the outpatient children.

CONCLUSION

Most children of 6 years of age and older, will show good cooperation with nasometry. In children aged 5, cooperation depends on the situation in which the nasometer is used. In a school setting the cooperation is better than in an outpatient clinic setting. In the 4 years old children the cooperation with the nasometer often is insufficient, probably due to normal, unpredictable cooperative behavior belonging to this age.

Nasometry normative data for young Dutch children

OBJECTIVE

Hypernasality is a common problem in cleft care. It should be treated before the age of six, because of the impact it can have on speech sound development in young children. An objective method of nasalance evaluation is nasometry. To decide whether a nasometer test result is normal or abnormal, normative data and cut off points are needed. Normative data for children are not available for every language and age. For Dutch children two sets of Dutch speech stimuli, the Van Zundert sentences or the Moolenaar-Bijl, sentences, are often used in the diagnostic process for hypernasality. Primary goal of this study is to determine normative data and cut off points for two sets of Dutch speech stimuli for Dutch children from four to six years of age. Secondary is to compare those two sets of oral sentences.

METHOD

Children without clefts were recruited from schools. According to their teachers their speech was normal. They were tested with the nasometer with the two sets of speech stimuli. The set from Van Zundert has oral and oronasal sentences, the Moolenaar-Bijl set only has oral sentences.

RESULTS

118 children were recruited. Out of these children, 55 produced recording samples which were suitable for analysis. There were no significant differences between age groups or gender. The two different sets of speech stimuli used were significantly different, but the confidence intervals overlapped.

CONCLUSIONS

Normal nasalance scores of the tested sentences are between 3 and 19% for oral sentences and between 17 and 37% for oronasal sentences. The Moolenaar-Bijl speech sentences are preferred to evaluate hypernasality in young Dutch children, because of the shortness and intelligibility. Normative nasalance scores are applicable to the whole group of children from four to six years of age.

Three monosyllables for standard words in Nasometer test: to evaluate air leakage in maxillectomy patients

PURPOSE

The purpose of this study was to establish an evaluation method using a Nasometer, with several monosyllabic test words, to reveal the level of air leakage in maxillectomy patients without limitations due to language or ability to read.

METHODS

20 normal Japanese (Group 1) and 20 international adults (Group 2), were asked to read 7 monosyllables, (5 vowels and 2 combined vowels, /a/, /i/, /u/, /e/, /o/, /am/, /aj/), 6 times each and 12 Japanese maxillectomy patients (Group 3) were asked to read only 3 monosyllables (/a/, /am/, /aj/) 6 times each. The "Nasalance Score" was calculated using a Nasometer (Nasometer II, model 6400 KayPentax, Lincoln Park, NJ, USA).

RESULTS

Coefficient of variations (CVs) of three monosyllables /a/, /am/, /aj/ of Group 1 and Group 2 showed less than 0.33. There is significant difference in all pairs of three monosyllables between Group 1 and Group 3 (p < 0.05).

CONCLUSION

Using a Nasometer, these three monosyllables, /a/, /am/ and /aj/, could be used as standard test words and could reveal the level of air leakage in maxillectomy patients.

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(trade mark) 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.

Midface osteotomy versus distraction: the effect on speech, nasality, and velopharyngeal function in craniofacial dysostosis

OBJECTIVE

To assess speech outcomes following midface advancement and to explore whether the type of advancement surgery affects speech differently in patients with craniofacial dysostosis.

DESIGN

Prospective, before-after group design.

SUBJECTS

Fifteen consecutive patients were included in the study. Eight underwent advancement by osteotomy and seven by distraction. All patients were seen preoperatively and at least once postoperatively.

MAIN OUTCOME MEASURES

Percentage of consonants correct, nature and type of articulation errors, nasalance score, severity ratings of resonance and of velopharyngeal function using nasendoscopy and lateral videofluoroscopy, and amount of forward advancement.

RESULTS

No statistically significant differences were found between groups for pre- and postoperative changes of percentage of consonants correct (p = .755, median difference 3.0, 95% confidence interval for median difference [-14.22, 20.22]) and nasalance (p = .171, median difference = -12.00, 95% confidence interval for median differences [-30.46, 6.46]). There was no statistically significant correlation between amount of forward advancement and nasalance (r = .87, p = .799) and percentage of consonants correct (r = -.550, p = .064). Findings from lateral videofluoroscopy and nasendoscopy are described. Individual changes of speech outcomes are reported.

CONCLUSIONS

In view of the small sample size, results need to be interpreted with caution. However, the study adds to current limited knowledge with this clinical group. Further research with bigger sample sizes and randomization of patients into the different surgical groups is warranted.

Vowel acoustic space development in children: a synthesis of acoustic and anatomic data

PURPOSE

This article integrates published acoustic data on the development of vowel production. Age specific data on formant frequencies are considered in the light of information on the development of the vocal tract (VT) to create an anatomic-acoustic description of the maturation of the vowel acoustic space for English.

METHOD

Literature searches identified 14 studies reporting data on vowel formant frequencies. Data on corner vowels are summarized graphically to show age- and sex- related changes in the area and shape of the traditional vowel quadrilateral.

CONCLUSIONS

Vowel development is expressed as follows: (a) establishment of a language-appropriate acoustic representation (e.g., F1-F2 quadrilateral or F1-F2-F3 space), (b) gradual reduction in formant frequencies and F1-F2 area with age, (c) reduction in formant-frequency variability, (d) emergence of male-female differences in formant frequency by age 4 years with more apparent differences by 8 years, (e) jumps in formant frequency at ages corresponding to growth spurts of the VT, and (f) a decline of f0 after age 1 year, with the decline being more rapid during early childhood and adolescence. Questions remain about optimal procedures for VT normalization and the exact relationship between VT growth and formant frequencies. Comments are included on nasalization and vocal fundamental frequency as they relate to the development of vowel production.