Development of a smartphone screening test for preclinical Alzheimer's disease and validation across the dementia continuum.

BACKGROUND: Dementia prevalence is predicted to triple to 152 million globally by 2050. Alzheimer's disease (AD) constitutes 70% of cases. There is an urgent need to identify individuals with preclinical AD, a 10-20-year period of progressive brain pathology without noticeable cognitive symptoms, for targeted risk reduction. Current tests of AD pathology are either too invasive, specialised or expensive for population-level assessments. Cognitive tests are normal in preclinical AD. Emerging evidence demonstrates that movement analysis is sensitive to AD across the disease continuum, including preclinical AD. Our new smartphone test, TapTalk, combines analysis of hand and speech-like movements to detect AD risk. This study aims to [1] determine which combinations of hand-speech movement data most accurately predict preclinical AD [2], determine usability, reliability, and validity of TapTalk in cognitively asymptomatic older adults and [3], prospectively validate TapTalk in older adults who have cognitive symptoms against cognitive tests and clinical diagnoses of Mild Cognitive Impairment and AD dementia. METHODS: Aim 1 will be addressed in a cross-sectional study of at least 500 cognitively asymptomatic older adults who will complete computerised tests comprising measures of hand motor control (finger tapping) and oro-motor control (syllabic diadochokinesis). So far, 1382 adults, mean (SD) age 66.20 (7.65) years, range 50-92 (72.07% female) have been recruited. Motor measures will be compared to a blood-based AD biomarker, phosphorylated tau 181 to develop an algorithm that classifies preclinical AD risk. Aim 2 comprises three sub-studies in cognitively asymptomatic adults: (i) a cross-sectional study of 30-40 adults to determine the validity of data collection from different types of smartphones, (ii) a prospective cohort study of 50-100 adults ≥ 50 years old to determine usability and test-retest reliability, and (iii) a prospective cohort study of ~1,000 adults ≥ 50 years old to validate against cognitive measures. Aim 3 will be addressed in a cross-sectional study of ~200 participants with cognitive symptoms to validate TapTalk against Montreal Cognitive Assessment and interdisciplinary consensus diagnosis. DISCUSSION: This study will establish the precision of TapTalk to identify preclinical AD and estimate risk of cognitive decline. If accurate, this innovative smartphone app will enable low-cost, accessible screening of individuals for AD risk. This will have wide applications in public health initiatives and clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06114914, 29 October 2023. Retrospectively registered.

Oral-diadochokinesis between Parkinson's disease and neurotypical elderly among Malaysian-Malay speakers.

BACKGROUND: Parkinson's disease (PD) has an impact on speech production, manifesting in various ways including alterations in voice quality, challenges in articulating sounds and a decrease in speech rate. Numerous investigations have been conducted to ascertain the oral-diadochokinesis (O-DDK) rate in individuals with PD. However, the existing literature lacks exploration of such O-DDK rates in Malaysia and does not provide consistent evidence regarding the advantage of real-word repetition. AIMS: To explore the effect of gender, stimuli type and PD status and their interactions on the O-DDK rates among Malaysian-Malay speakers. METHODS & PROCEDURES: O-DDK performance of 62 participants (29 individuals with PD and 33 healthy elderly) using a non-word ('pataka'), a Malay real-word ('patahkan') and an English real-word ('buttercake') was audio recorded. The number of syllables produced in 8 s was counted. A hierarchical linear modelling was performed to investigate the effects of stimuli type (non-word, Malay real-word, English real-word), PD status (yes, no), gender (male, female) and their interactions on the O-DDK rate. The model accounted for participants' age as well as the nesting of repeated measurements within participants, thereby providing unbiased estimates of the effects. OUTCOMES & RESULTS: The stimuli effect was significant (p < 0.0001). Malay real-word showed the lowest O-DDK rate (5.03 ± 0.11 syllables/s), followed by English real-word (5.25 ± 0.11 syllables/s) and non-word (5.42 ± 0.11 syllables/s). Individuals with PD showed a significantly lower O-DDK rate compared to healthy elderly (4.73 ± 0.15 syllables/s vs. 5.74 ± 0.14 syllables/s, adjusted p < 0.001). A subsequent analysis indicated that the O-DDK rate declined in a quadratic pattern. However, neither gender nor age effects were observed. Additionally, no significant two-way interactions were found between stimuli type, PD status and gender (all p > 0.05). Therefore, the choice of stimuli type has no or only limited effect considering the use of O-DDK tests in clinical practice for diagnostic purposes. CONCLUSIONS & IMPLICATIONS: The observed slowness in O-DDK among individuals with PD can be attributed to the impact of the movement disorder, specifically bradykinesia, on the physiological aspects of speech production. Speech-language pathologists can gain insights into the impact of PD on speech production and tailor appropriate intervention strategies to address the specific needs of individuals with PD according to disease stages. WHAT THIS PAPER ADDS: What is already known on this subject The observed slowness in O-DDK rates among individuals with PD may stem from the movement disorder's effects on the physiological aspects of speech production, particularly bradykinesia. However, there is a lack of consistent evidence regarding the influence of real-word repetition and how O-DDK rates vary across different PD stages. What this study adds to existing knowledge The O-DDK rates decline in a quadratic pattern as the PD progresses. The research provides insights into the advantage of real-word repetition in assessing O-DDK rates, with Malay real-word showing the lowest O-DDK rate, followed by English real-word and non-word. What are the potential or actual clinical implications of this work? Speech-language pathologists can better understand the evolving nature of speech motor impairments as PD progresses. This insight enables them to design targeted intervention strategies that are sensitive to the specific needs and challenges associated with each PD stage. This finding can guide clinicians in selecting appropriate assessment tools for evaluating speech motor function in PD patients.

Can oral diadochokinesis be used as an assessment tool of oral function in older adults requiring care in nursing home?

BACKGROUND: Oral diadochokinesis (OD) test is an articulation test that analyses fine movements of the lips, cheeks and tongue. It is difficult to perform the test accurately in older people with reduced physical and cognitive functions. OBJECTIVES: This study aimed to investigate the number of older adults who could not be tested for OD and to investigate their characteristics. METHODS: The participants included 145 older residents of an aged care nursing home. They were divided into two groups: those who could be tested for OD and those who could not, and their characteristics were compared. The degree of requiring long-term care was classified into five levels. The degree of dementia was classified into five levels. Those having difficulty in performing daily activities alone and having degree III or higher dementia were considered to have severe dementia. RESULTS: The participants included 41 men and 104 women with a median age of 89 years (range, 64-105 years). Sixty-eight participants failed the OD test (46.9%). In univariate and multivariate analyses, degree of dementia and oral care (among other characteristics in univariate analysis) showed statistically significant differences between the two groups. Cut-off values for older adults who could not perform OD test were level 4 or higher in need of care and degree III or higher in dementia. CONCLUSION: This study suggests that additional assessment tools for oral function should be considered for older adults requiring a nursing care level of 4 or higher and a dementia degree of III or higher.

[Association between depressive tendencies and oral diadochokinesis in the older adults in private residential nursing home].

AIM: This study aimed to investigate the relationship between depressive tendencies and oral diadochokinesis (ODK) in 24 older adults living in a private residential nursing home. ODK is an indicator of the oral function. METHODS: Depressive tendencies were assessed using the Geriatric Depression Scale 5, with scores of two or higher indicating probable depression. ODK was measured across four syllable tasks (/pa/, /ta/, /ka/, and /pataka/), which were evaluated using coefficient of variation (CV) values. Low CV values indicate superior performance. Potential confounders, including the cognitive function, sleep status, body mass index, instrumental activities of daily living, and physical function, were controlled. RESULTS: Five participants (20.8%) experienced depression. Individuals with depressive tendencies demonstrated significantly poor ODK performance (higher CV) in the /ta/ task and a marginally significant difference in the /ka/ task. No significant differences were observed between /pa/ and /pataka/. CONCLUSIONS: These findings suggest a link between depressive tendencies and reduced proficiency in specific ODK tasks among older nursing home residents. This finding implies that a decline in the oral function in articulating /ta/ and /ka/ syllables may precede other common depressive symptoms. Furthermore, depression monitoring could be a valuable tool for early detection of the oral function in this population, enabling timely interventions.

Oral diadochokinetic production in children with typical speech development and speech-sound disorders.

BACKGROUND: AIMS: To investigate the developmental trajectory of the rate and perceptual assessment of oral diadochokinesis (DDK) in typically developing children compared with adults. Also to examine the characteristics of DDK productions in children with speech sound disorders (SSD) and the relationship between DDK production and percentage of consonants correct (PCC). METHODS & PROCEDURES: Participants were 316 typically developing children and 90 children with SSD from 3 to 9 years old, as well as 20 adults with normal speech. The mono-, bi- and trisyllabic nonsense strings containing Korean tense consonants and the vowel [a] were used for DDK tasks. The number of iterations per s was measured as the DDK rate for each stimulus. The perceptual assessment of DDK productions was also performed for regularity, accuracy and rate. OUTCOMES & RESULTS: The DDK rates increased throughout childhood, but the oldest children, 9-year-olds in the current study, did not achieve adult-like rates for all mono- and trisyllabic strings. Children with SSD also did not show significant differences from typically developing children when the DDK productions were analysed using only accurate tokens. The PCC of children with SSD showed higher correlations with regularity, accuracy and rate of perceptual ratings than the timed DDK rate. CONCLUSIONS & IMPLICATIONS: This study highlighted the fact that the comprehensive evaluation of DDK productions may provide even more useful information about children's oral motor skills. WHAT THIS PAPER ADDS: What is already known on the subject Rates of DDK reflect the motor skills of the articulatory systems independently of phonological skills; therefore, the tasks are widely used in the diagnostic evaluations of speech disorders in both children and adult populations. However, a substantial number of studies have questioned the validity and usefulness of DDK rates for evaluating speech abilities. Also, the literature suggested that the measure of DDK rate alone does not provide a clear and useful indication of children's oral motor skills. DDK tasks should be analysed in terms of accuracy and consistency as well as rate. What this paper adds to the existing knowledge The literature reporting normative DDK performance has mainly been based on English speakers. As different consonants have different temporal characteristics, the linguistic and segmental features of DDK tasks can impact the DDK rate. This study established a norm for DDK rate for Korean-speaking children and investigated the developmental trajectory of DDK performance in typically developing children compared with adults. This study suggested that the comprehensive evaluation of DDK productions may provide even more useful information about children's oral motor skills by examining the characteristics of DDK productions in children with SSD. What are the potential or actual clinical implications of this work? This study provided normative data of young Korean-speaking children aged 3-9 years. Normative data in children under 5 years of age are valuable given that the majority of children referred for speech difficulty assessments are between 3 and 5 years of age, but only a few studies have provided the normative data in young children. This study showed that many children could not complete DDK tasks correctly and provided additional support for the notion that other aspects of DDK performance, including accuracy and regularity, may yield more useful diagnostic indications than timed DDK rates alone.

Oral-motor function in older people: Exploring new dimensions of frailty.

BACKGROUND: Oral-motor performance for speech and swallowing, and verbal fluency represent important domains that can determine frailty thresholds in older people. OBJECTIVES: The study aims to explore the association between oral-motor performance and verbal fluency to achieve a comprehensive measurement of the frailty phenotype. METHODS AND PROCEDURES: An exploratory and inferential cross-sectional study was carried out in two nursing homes and 2 day care centres. The study comprised a sample of 95 individuals with a mean age of 83 years. The oral-diadochokinesis test (ODDK), water swallow test (WST), time of mastication and swallowing (TOMASS), maximum tongue pressure, verbal fluency, physical phenotype and Mini-Mental State Examination (MMSE) were used as measurements variables. RESULTS: The comparison of mean values between the performance of observed and normative values for the target population was shown to be statistically significant for all the measurements and between the pre-frail and frail. CONCLUSIONS: The results of this study add to the growing body of evidence that oral-motor function for speech and swallowing and verbal fluency are relevant to the diagnosis and management of the frailty condition in older people. The frailty syndrome is more than just the traditionally observed physical function, rather it is a multidimensional construct, where additional dimensions should be considered when evaluating frailty in clinical practice.

Laryngeal Diadochokinesis in the Mandarin Population.

INTRODUCTION: This study identifies the most suitable syllable for laryngeal diadochokinesis (LDDK) in Mandarin speakers. METHODS: One hundred and ten Mandarin speakers aged 18-83 years were used in the study. LDDK was assessed using quick repetitions of /ʔe/, /ʔi/, /ʔa/, /he/, /ha/, and /hi/. The observation index included the average rate (syllable/s) and regularity (%). RESULTS: In the various age groups, there was no significant difference in LDDK rate and regularity of adducted syllables (p > 0.05), and only the regularity of /ʔi/ is significantly different between aged 18-40 and 41-64 years (p = 0.040). When vocal fold adduction was compared between various syllables, there was no significant difference in LDDK rate and regularity (p > 0.05). In various age groups, the LDDK rate of abduction syllables is different (p < 0.05) compared with the LDDK regularity of abduction syllables (p > 0.05). In various abduction syllables, there is no difference in LDDK rate (p > 0.05); however, /ha/ and /hi/ have significant differences in LDDK regularity (p = 0.007). CONCLUSION: According to the preliminary data, /ʔa/ and /ha/ can be used as suitable indicators to analyse the coordination ability of the laryngeal movement of Mandarin speakers.

Oral exercises significantly improve oral functions in people with mild and moderate dementia: A randomised controlled study.

BACKGROUND: There have been no standard protocols of oral exercises for maintaining and improving oral function for people with dementia. OBJECTIVE: This study aimed to determine the effects of home-based oral exercises on the oral function of people with mild to moderate dementia. METHODS: Twenty-two participants at King Chulalongkorn Memorial Hospital were randomly assigned to the exercise group (n = 11) or control group (n = 11). The exercise group was instructed to do three home-based oral exercises, consisting of tongue-strengthening, oral diadochokinesis (ODK) and mouth-opening exercises, for 3 months, while the control group received advice on oral health care. The maximum tongue pressure (MTP) was the primary outcome. MTP, ODK rates of /pa/, /ta/, /ka/, modified water swallowing test (MWST) and oral moisture were measured at baseline, and after 1, 2 and 3 months of training. The generalised estimating equation analysis was used to evaluate the effects of oral exercises on the oral function. RESULTS: The MTP and all ODK rates in the exercise group were significantly increased after 3 months of training. There were significant interaction effects between time and intervention in MTP and all ODK rates. No significant interaction effects between time and intervention in oral moisture were found. The MWST scores in both groups did not change through the end of study, and no adverse effects were reported. CONCLUSION: Home-based oral exercises were found to be effective for improving tongue strength and tongue-lip motor function in people with mild to moderate dementia.

Impact of oral health guidance on the tongue-lip motor function of outpatients at a dental hospital.

OBJECTIVE: To clarify the effect of oral health guidance on tongue-lip motor function in the outpatients visiting the Showa University Dental Hospital (Tokyo, Japan). BACKGROUND: The management of the oral function of older people visiting a dental hospital is important. Previous studies have revealed that tongue-lip motor function is easy to improve. However, the impact of oral health guidance on tongue-lip motor function in the outpatients of dental hospital requires further elucidation. MATERIALS AND METHODS: The participants (n = 35) included patients who were diagnosed with low tongue-lip motor function on evaluation by oral diadochokinesis (ODK) at the outpatient clinic. They underwent a second examination approximately 6-12 months later. Their demographic characteristics were recorded. Oral health guidance was provided through an educational leaflet on oral hypofunction when the participants visited the clinic. It included content on tongue twisters, voice training and a range of movement and muscle training of the tongue and lip. RESULTS: Following oral health guidance on tongue-lip motor function, the ODK values changed from 5.6 at the first examination to 6.0 at the second for /pa/, from 5.6 to 5.8 for /ta/ and from 5.2 to 5.4 for /ka/. This improvement was not significantly associated with age, sex, measurement period or number of visits. CONCLUSION: The findings of this longitudinal study suggested that oral health guidance using an oral hypofunction educational leaflet may be effective in improving the tongue-lip motor function of outpatients who had low tongue-lip motor function, regardless of the measurement period or the number of visits to the dental hospital.

Oral diadochokinesis and associated oro-facial function in young and old German mother-tongue speakers: A cross-sectional study.

OBJECTIVES: The aims of this study were to compare oral diadochokinesis and to test associations with oro-facial functional parameters in healthy young and old German speakers. BACKGROUND: Oral diadochokinesis is a key component in the concept of oro-facial hypofunction and relates to tongue and lip motor function but may depend on the linguistic background. MATERIALS AND METHODS: Healthy German speakers with a minimum of 20 teeth were recruited to form a young (<60 years) and an older group (≥60 years). Oral diadochokinesis was assessed as the number of repetitions/s for the monosyllables /pa/, /ta/ and /ka/ to evaluate movement capacity of the lip, the anterior region of the tongue and the posterior region of the tongue, respectively. Maximum voluntary lip force, maximum voluntary bite force, masticatory performance, maximum voluntary tongue pressure, xerostomia and swallowing function were assessed with validated instruments. Results are presented as median (IQR). RESULTS: Sixty participants formed the younger group (n = 35, 30.0 years [24.0-49.0]) and the older group (n = 25, 64.0 years [62.0-72.0]). Counts/s of /ta/ were different between age groups (younger group: 6.0 vs older group: 5.4) but not for syllables /pa/ (younger group: 6.0 vs older group: 5.8) and /ka/ (younger group: 5.6 vs older group: 5.0). The oral diadochokinesis with /pa/ was overall associated with maximum voluntary lip force; oral diadochokinesis performed with /ta/ was associated with tongue pressure, and oral diadochokinesis with /ka/ with swallowing function. Masticatory performance was not associated with oral diadochokinesis but with maximum voluntary bite force, xerostomia and with maximum voluntary tongue pressure. CONCLUSIONS: The published thresholds for oral diadochokinesis should be reconsidered in non-Japanese mother-tongue speakers. However, they still play an important role in the overall concept of oro-facial functional assessment.

Oral diadochokinesis is related to decline in swallowing function among community-dwelling Japanese elderly: a cross-sectional study.

BACKGROUND: Since oral organs function in the first stage of the swallowing process, it is possible that decline in swallowing function can be partly related to oral frailty. AIMS: The purpose of this study was to investigate the association between swallowing function and oral function among community-dwelling elderly Japanese and to propose cut-off values for screening of decline in swallowing function. METHODS: A total of 188 participants were included in the analysis. The number of present teeth and functioning teeth were counted. Bacteria counts in tongue coat, oral wettability, tongue pressure, oral diadochokinesis (ODK), masticatory ability and bite force were examined. Swallowing function was assessed using the 10-item Eating Assessment Tool (EAT-10). Receiver operating characteristic curves were used to determine the cut-off points of each oral function parameter. A logistic regression model was performed to determine the combination of parameters with the highest accuracy for differentiating decline in swallowing function from normal. RESULTS: Subjects with ODK /pa/ sound < 6.2 times/second had higher prevalence of swallowing problems than those with 6.2 times/second or more. EAT-10 scores of one or more were significantly related to older age (≥ 71 years old; odds ratio [OR] 4.321) and reduced ODK /pa/ sound (< 6.2 times/second; OR 2.914). CONCLUSIONS: Among community-dwelling elderly Japanese, those who were suspected of having decline in swallowing function had lower oral function than those who did not, and the cut-off values were 71 years of age and ODK /pa/ sound 6.2 times/s.

Tongue pressure waveform analysis for ascertaining the influence of tongue muscle composition on articulation.

BACKGROUND: Rate force development is associated with performance and muscle composition in whole-body muscle. Although rate force development on tongue muscle can be examined using tongue pressure waveform, there have been only few investigations on this topic. OBJECTIVES: This study's main purpose was to investigate the reliability of tongue pressure waveform analysis and its relationship with articulation and tongue muscle composition. In addition, we also investigated the association between tongue muscle composition and articulation. METHODS: Forty-five community-dwelling individuals aged >20 years participated. We analysed tongue pressure waveform, including maximum tongue pressure (MTP), time to peak, mean rate of tongue force development and peak rate of tongue force development (PRTFD). We also assessed oral diadochokinesis. Magnetic resonance imaging of the tongue provided data on tongue muscle composition, including tongue volume, fat mass, lean muscle mass and fat percentage. We evaluated the reliability of tongue pressure waveform analysis. Moreover, we examined the coefficients between tongue pressure waveform analysis, oral diadochokinesis and tongue composition. RESULTS: We detected a high reliability of MTP and PRTFD. MTP and PRTFD were significantly correlated with tongue muscle composition. MTP was not significantly correlated with oral diadochokinesis. PRTFD was significantly positively correlated with oral diadochokinesis. Tongue fat mass and fat percentage were negatively correlated with oral diadochokinesis of /ta/ and /ka/. CONCLUSIONS: Peak rate of tongue force development is a highly reliable method for tongue pressure analysis and is useful for elucidating the functional importance of tongue muscle function on articulation. We speculated that fatty infiltration of the tongue adversely affects articulation.

The relationship between sarcopenia and oral sarcopenia in elderly people.

BACKGROUND: Sarcopenia in the oral region, including the tongue, leads to declined swallowing function and dysphagia. Muscle mass and strength, and motor function in the oral region have not been examined together, and the relationship between generalised and oral sarcopenia remains unclear. OBJECTIVE(S): The purpose of this study is to clarify the relationship between generalised sarcopenia and oral sarcopenia in the elderly in order to facilitate the establishment of a method for assessing oral sarcopenia. METHODS: A total of 54 elderly persons participated in this study. We examined the skeletal muscle mass index (SMI), grip strength (GS) and walking speed (WS) as the index of generalised sarcopenia, and the cross-sectional area of the geniohyoid muscle (CSG), tongue pressure (TP) and oral diadochokinesis (ODK) as the index of oral sarcopenia. RESULTS: We found a moderate correlation between CSG and SMI, a weak correlation between GS and TP, and a moderate correlation between WS and ODK. CSG, TP and ODK were significantly smaller in the sarcopenia group than in the non-sarcopenia group. By multiple regression analysis, SMI and TP were significantly associated with CSG. ODK, BMI and CSG were significantly associated with TP. WS and SMI were significantly associated with ODK. CONCLUSION: CSG, TP and ODK were confirmed as endpoints of oral sarcopenia. All endpoints of oral sarcopenia were influenced by those of generalised sarcopenia.

Associations of Oral Health-Related Quality of Life with age, oral status, and oral function among psychiatric inpatients in Japan: a cross-sectional study.

BACKGROUND: As the general population of Japan ages, the population of hospitalized psychiatric patients is also ageing. The purpose of this study was to investigate the associations of oral health-related quality of life (OHRQoL) with age and oral health, including oral and swallowing function, among psychiatric inpatients. METHODS: The subjects included 165 psychiatric inpatients in psychiatric hospitals in Japan. The General Oral Health Assessment Index (GOHAI) and the Eating Assessment Tool (EAT-10) were included in the questionnaire survey for the measurement of OHRQoL and the screening of dysphagia. A score ≥ 3 on the EAT-10 was defined as suspected dysphagia. Oral examinations and oral diadochokinesis (ODK) measurements for the tongue-lip motor function evaluation were conducted. The inpatients with acute psychiatric symptoms, moderate and severe dementia, and cognitive impairment that affected their ability to communicate and relate their feelings were excluded. A chi-squared test, the Mann-Whitney U test, and linear regression analysis were used for the analysis. The data were analysed at the 5% significance level. RESULTS: A total of 100 (64.5%) psychiatric inpatients (mean age, 67.3 [SD, 14.5] years, 49% males, and 51% females) participated in this study. The means ± SDs for the decayed missing filled teeth (DMFT) index and GOHAI score were 20.6 ± 6 and 49.7 ± 7.9, respectively. The GOHAI score in the older age group (≥ 65 years) was significantly lower than that in the younger age group (< 65 years). The mean ODK scores were less than 3 times/s for all syllables. The percentage of the participants with suspected dysphagia was 45.0%. Tooth loss and suspected dysphagia were significantly associated with low GOHAI scores. The EAT-10 score was significantly correlated with the GOHAI score only after adjusting for age and sex (ß = - 0.725, 95% CI - 0.97, - 0.64). CONCLUSIONS: In hospitalized psychiatric patients, impaired oral health in the older subjects was more pronounced compared with that among general adults. Tooth loss and swallowing function were associated with OHRQoL. Therefore, oral care for the recovery of occlusal and swallowing functions may be needed to improve OHRQoL among psychiatric patients.

Association between tongue and lip motor functions and mixing ability in complete denture wearers.

BACKGROUND: Masticatory performance of elderly complete denture wearers is low, which may lead to restriction on intakes of several foods such as fresh fruit or raw vegetables. AIM: The aim of this study was to investigate the relationship between tongue motor function, lip motor function, and mixing ability in complete denture wearers. MATERIALS AND METHODS: Participants comprised 54 complete denture wearers with a mean age of 77.1 years. Maximum tongue pressure and oral diadochokinesis were measured to evaluate tongue and lip motor functions. A color-changeable, chewing gum was used to evaluate mixing ability. The relationship between tongue and lip motor functions and mixing ability was assessed using stepwise multiple regression analysis. RESULTS: The stepwise multiple regression analysis identified maximum tongue pressure, the number of repetitions of the syllable "ka", and gender as significant predictors for mixing ability among complete denture wearers. DISCUSSION: The elderly edentulous individuals mainly used tongue motor function in oral motor functions for mixing color-changeable chewing gums, which might be ascribable to wearing complete dentures. CONCLUSIONS: Under the limited conditions of this study, factors relating to tongue motor function, tongue pressure and the number of repetitions of the syllable "/ka"/ significantly contributed to the mixing ability of complete denture wearers. It was suggested that tongue motor function had positive effect on the mixing ability of complete denture wearers.

Association between echo intensity of the tongue and its thickness and function in elderly subjects.

BACKGROUND: The tongue plays an important role during the oropharyngeal phase of swallowing. Each part of the tongue has a different function during swallowing. Ageing causes changes in muscle quantity and quality. Qualitative changes, such as an increase in intramuscular adipose tissue, can be determined by the echo intensity (EI) of the tongue on ultrasonography (US). OBJECTIVE: To clarify the relationship between EI and thickness and function of the tongue. METHODS: Ninety-four healthy elderly individuals (30 male, 64 female) aged >65 years (mean 71.10 ± 4.13 years) were enrolled. Tongue thickness (TT) and EI were determined by US. Tongue function was evaluated by measurement of tongue pressure and oral diadochokinesis (OD). Multiple regression analysis was used to identify the factor with the strongest influence on EI of the tongue. RESULTS: The mean thickness of the middle of the tongue was 40.42 ± 4.24 mm and that of the base was 23.35 ± 3.32 mm; the respective EI values were 46.54 ± 9.33 and 49.33 ± 9.83. The average OD rates for /ta/ and /ka/ were 5.73 ± 1.09 and 5.40 ± 1.00 times/s, respectively. Multiple regression analysis for EI showed that /ta/ (ß = -2.518, P = 0.042) and thickness of the middle of the tongue (ß = -1.278, P < 0.001) were significant independent variables. Similarly, the EI at the base of the tongue showed that /ka/ (ß = -4.038, P = 0.021) and base of TT (ß = -0.913, P = 0.004) were significant independent variables. CONCLUSION: EI may be an indicator of TT and OD in both the middle and base of the tongue. Ultrasound is beneficial for evaluating TT and function.

The Effect of Practice and Visual Feedback on Oral-Diadochokinetic Rates for Younger and Older Adults.

Assessments of oral-diadochokinetic rates are commonly performed to evaluate oral-motor skills. However, the appropriate administration protocol is not defined, and varies across therapists, clinics and laboratories. In three experiments and an auxiliary one, this study analyzes the effects of brief (motor) practice and visual feedback on the performance of 98 younger (20-40 years old) and 78 older adults (over 65) with the sequential motion rate (SMR) version. Overall rates were significantly faster for younger over older adults. Irrespective of age-group, averaged performance was significantly better on the second round, but the third round was found to be superfluous, across experiments and age-groups. Visual feedback (using a mirror) was found to be detrimental for younger adults, eliminating the advantage reaped from a practice round. For older adults, visual feedback did not alter the effect of a practice round. Sensory (visual) degradation is presented as a possible source for this age-related difference. We discuss these findings and suggest an administration protocol for younger and older adults with the SMR version, including a total of two rounds and no visual feedback.

Oral-diadochokinetic rates for Hebrew-speaking healthy ageing population: non-word versus real-word repetition.

BACKGROUND: Oral-diadochokinesis (oral-DDK) tasks are extensively used in the evaluation of motor speech abilities. Currently, validated normative data for older adults (aged 65 years and older) are missing in Hebrew. The effect of task stimuli (non-word versus real-word repetition) is also non-clear in the population of older adult Hebrew speakers. AIMS: (1) To establish a norm for oral-DDK rate for older adult (aged 65 years and older) Hebrew speakers, and to investigate the possible effect of age and gender on performance rate; and (2) to examine the effects of stimuli (non-word versus real word) on oral-DDK rates. METHODS & PROCEDURES: In experiment 1, 88 healthy older Hebrew speakers (60-95 years, 48 females and 40 males) were audio-recorded while performing an oral-DDK task (repetition of /pataka/), and repetition rates (syllables/s) were coded. In experiment 2, the effect of real-word repetition was evaluated. Sixty-eight older Hebrew speakers (aged 66-95 years, 43 females and 25 males) were asked to repeat 'pataka' (non-word) and 'bodeket' (Hebrew real word). OUTCOMES & RESULTS: Experiment 1: Oral-DDK performance for older adult Hebrew speakers was 5.07 syllables/s (SD = 1.16 syllables/s), across age groups and gender. Comparison of this data with Hebrew norms for younger adults (and equivalent data in English) shows the following gradient of oral-DDK rates: ages 15-45 > 65-74 > 75-86 years. Gender was not a significant factor in our data. Experiment 2: Repetition of real words was faster than that of non-words, by 13.5%. CONCLUSIONS & IMPLICATIONS: The paper provides normative values for oral-DDK rates for older Hebrew speakers. The data show the large impact of ageing on oro-motor functions. The analysis further indicates that speech and language pathologists should consider separate norms for clients of 65-74 years and those of 75-86 years. Hebrew rates were found to be different from English norms for the oldest group, shedding light on the impact of language on these norms. Finally, the data support using a dual-protocol (real- and non-word repetition) with older adults to improve differential diagnosis of normal and pathological ageing in this task.

Meaningful Words and Non-Words Repetitive Articulatory Rate (Oral Diadochokinesis) in Persian Speaking Children.

Repetitive articulatory rate or Oral Diadochokinesis (oral-DDK) shows a guideline for appraisal and diagnosis of subjects with oral-motor disorder. Traditionally, meaningless words repetition has been utilized in this task and preschool children have challenges with them. Therefore, we aimed to determine some meaningful words in order to test oral-DDK in Persian speaking preschool children. Participants were 142 normally developing children, (age range 4-6 years), who were asked to produce /motæka, golabi/ as two meaningful Persian words and /pa-ta-ka/ as non-word in conventional oral-DDK task. We compared the time taken for 10-times fast repetitions of two meaningful Persian words and the tri-syllabic nonsense word /pa-ta-ka/. Praat software was used to calculate the average time that subjects took to produce the target items. In 4-5 year old children, [Formula: see text] of time taken for 10-times repetitions of /pa-ta-ka, motæka, golabi/ were [Formula: see text], and [Formula: see text] seconds respectively, and in 5-6 year old children were [Formula: see text], and [Formula: see text] seconds respectively. Findings showed that the main effect of type of words on oral diadochokinesis was significant ([Formula: see text]). Children repeated meaningful words /motæka, golabi/ faster than the non-word /pa-ta-ka/. Sex and age factors had no effect on time taken for repetition of oral-DDK test. It is suggested that Speech Therapists can use meaningful words to facilitate oral-DDK test for children.

Analysis and Visualization of 3D Motion Data for UPDRS Rating of Patients with Parkinson's Disease.

Remote monitoring of Parkinson's Disease (PD) patients with inertia sensors is a relevant method for a better assessment of symptoms. We present a new approach for symptom quantification based on motion data: the automatic Unified Parkinson Disease Rating Scale (UPDRS) classification in combination with an animated 3D avatar giving the neurologist the impression of having the patient live in front of him. In this study we compared the UPDRS ratings of the pronation-supination task derived from: (a) an examination based on video recordings as a clinical reference; (b) an automatically classified UPDRS; and (c) a UPDRS rating from the assessment of the animated 3D avatar. Data were recorded using Magnetic, Angular Rate, Gravity (MARG) sensors with 15 subjects performing a pronation-supination movement of the hand. After preprocessing, the data were classified with a J48 classifier and animated as a 3D avatar. Video recording of the movements, as well as the 3D avatar, were examined by movement disorder specialists and rated by UPDRS. The mean agreement between the ratings based on video and (b) the automatically classified UPDRS is 0.48 and with (c) the 3D avatar it is 0.47. The 3D avatar is similarly suitable for assessing the UPDRS as video recordings for the examined task and will be further developed by the research team.