Megan J. McAuliffe

Speech Production in Parkinson's Disease: I. An Electropalatographic Investigation of Tongue-Palate Contact Patterns.

Previous studies have indicated that consonant imprecision in Parkinsons disease (PD) may result from a reduction in amplitude of lingual movements or articulatory undershoot. While this has been postulated, direct measurement of the tongues contact with the hard palate during speech production has not been undertaken. Therefore, the present study aimed to use electropalatography (EPG) to determine the exact nature of tongue‐palate contact in a group of individuals with PD and consonant imprecision (n = 9). Furthermore, the current investigation also aimed to compare the results of the participants with PD to a group of aged (n = 7) and young (n = 8) control speakers to determine the relative contribution of ageing of the lingual musculature to any articulatory deficits noted. Participants were required to read aloud the phrase ‘I saw a ___ today’ with the artificial palate in‐situ. Target words included the consonants /l/, /s/ and /t/ in initial position in both the /i/ and /a/ vowel environments. Phonetic transcription of phoneme productions and description of error types was completed. Furthermore, representative frames of contact were employed to describe the features of tongue‐palate contact and to calculate spatial palatal indices. Results of the perceptual investigation revealed that perceived undershooting of articulatory targets distinguished the participant group with PD from the control groups. However, objective EPG assessment indicated that undershooting of the target consonant was not the cause of the perceived articulatory errors. It is, therefore, possible that reduced pressure of tongue contact with the hard palate, sub‐lingual deficits or impaired articulatory timing resulted in the perceived undershooting of the target consonants.

Familiarisation conditions and the mechanisms that underlie improved recognition of dysarthric speech

This investigation evaluated the familiarisation conditions required to promote subsequent and more long-term improvements in perceptual processing of dysarthric speech and examined the cognitive-perceptual processes that may underlie the experience-evoked learning response. Sixty listeners were randomly allocated to one of three experimental groups and were familiarised under the following conditions: (1) neurologically intact speech (control), (2) dysarthric speech (passive familiarisation), and (3) dysarthric speech coupled with written information (explicit familiarisation). All listeners completed an identical phrase transcription task immediately following familiarisation, and listeners familiarised with dysarthric speech also completed a follow-up phrase transcription task 7 days later. Listener transcripts were analysed for a measure of intelligibility (percent words correct), as well as error patterns at a segmental (percent syllable resemblance) and suprasegmental (lexical boundary errors) level of perceptual processing. The study found that intelligibility scores for listeners familiarised with dysarthric speech were significantly greater than those of the control group, with the greatest and most robust gains afforded by the explicit familiarisation condition. Relative perceptual gains in detecting phonetic and prosodic aspects of the signal varied dependent upon the familiarisation conditions, suggesting that passive familiarisation may recruit a different learning mechanism to that of a more explicit familiarisation experience involving supplementary written information. It appears that decisions regarding resource allocation during subsequent processing of dysarthric speech may be informed by the information afforded by the conditions of familiarisation.

Acoustic and perceptual analysis of speech adaptation to an artificial palate

The study investigated adaptation to a standard electropalatographic (EPG) practise palate in a group of eight adults (mean age = 24 years). The participants read the phrase “a CVC” over four sampling conditions: prior to inserting the palate, immediately following insertion of the palate, 45 minutes after palate insertion, and 3 hours after insertion of the palate. Perceptual and acoustic analyses were conducted on the initial CV portion of the stimuli. Consonants examined included: /t/, /k/, /s/, and /∫/ followed by the /i/, /a/, and /u/ vowels. Results revealed that individuals within the group were able to adapt their speech articulation to compensate for the presence of the artificial palate. Perceptually, mild consonant imprecision was observed upon insertion of the palate; however, this resolved following 45 minutes to 3 hours of adaptation. Acoustic findings indicated that the palate did not affect segment durations or vowel formant frequencies. However, a significant reduction in M1 for /s/ persisted across the sampling periods. Overall, the results suggest that a period of between 45 minutes and 3 hours of adaptation is generally suitable for participation in EPG studies.

The role of linguistic and indexical information in improved recognition of dysarthric speech

This investigation examined perceptual learning of dysarthric speech. Forty listeners were randomly assigned to one of two identification training tasks, aimed at highlighting either the linguistic (word identification task) or indexical (speaker identification task) properties of the neurologically degraded signal. Twenty additional listeners served as a control group, passively exposed to the training stimuli. Immediately following exposure to dysarthric speech, all three listener groups completed an identical phrase transcription task. Analysis of listener transcripts revealed remarkably similar intelligibility improvements for listeners trained to attend to either the linguistic or the indexical properties of the signal. Perceptual learning effects were also evaluated with regards to underlying error patterns indicative of segmental and suprasegmental processing. The findings of this study suggest that elements within both the linguistic and indexical properties of the dysarthric signal are learnable and interact to promote improved processing of this type and severity of speech degradation. Thus, the current study extends support for the development of a model of perceptual processing in which the learning of indexical properties is encoded and retained in conjunction with linguistic properties of the signal.

Intervention for lateral /s/ using electropalatography (EPG) biofeedback and an intensive motor learning approach: a case report

BACKGROUND Visual biofeedback using electropalatography (EPG) has been beneficial in the treatment of some cases of lateral /s/ misarticulation. While EPG intervention is motorically based, studies have not commonly employed a motor learning approach to treatment. Furthermore, treatment success is measured primarily by change to EPG tongue-palate contact patterns and listener ratings conducted by speech-language therapists. Studies have not commonly measured articulatory change without the palate in-situ using acoustic analysis and non-professional listeners. AIMS To determine if an intensive treatment programme including both visual biofeedback (EPG) and traditional articulation techniques within a motor learning paradigm would result in functional improvement to /s/ articulation in an 11-year-old girl with persistent lateral misarticulation. METHODS & PROCEDURES Treatment involved 12 sessions of therapist-delivered treatment over 4 weeks followed by a 6-week home programme. Outcomes of the treatment programme were measured primarily using naive listener ratings and acoustic analysis of /s/ spectra. OUTCOMES & RESULTS Improvements to both the perceptual and spectral characteristics of /s/ articulation occurred following the treatment programme. CONCLUSIONS The study highlighted the benefit of an intensive approach to intervention incorporating both visual biofeedback and traditional articulation approaches. The inclusion of a 6-week structured home-programme was beneficial and resulted in consolidation of treatment gains.

Speech intelligibility and perceptions of communication effectiveness by speakers with dysarthria following traumatic brain injury and their communication partners

Primary objective: This study examined differences in perceived communicative effectiveness between a group of eight participants with chronic dysarthria following TBI and their nominated communication partners (TBIP). The relationship between communicative effectiveness and listener ratings of speech intelligibility was also examined. Research design: Group comparison design. Methods and procedures: The Communicative Effectiveness Survey was completed by the participants with TBI and their communication partner. Speech intelligibility of the eight adults with dysarthria was rated by nine naive listeners using direct magnitude estimation. Main outcomes and results: The participants with TBI tended to rate their communicative effectiveness higher than their TBIP; however, this trend was not significant. No significant differences were noted between the TBI and TBIP groups in ratings of communicative effectiveness in various communication settings. No significant relationship was found between conversation level intelligibility and perceptions of communicative effectiveness, as rated by individuals with TBI and TBIP. Conclusions: The findings of this study highlight the need for collaborative participation in the therapeutic process by all stakeholders. The lack of correlation between speech intelligibility and perceived communicative effectiveness highlights the need for careful examination of activity and participation during assessment and goal-setting.

Treatment of articulatory impairment in a child with spastic dysarthria associated with cerebral palsy.

Background: A comparative study of treatment modalities for improving articulation in a 13-year-old child with severe spastic dysarthria associated with spastic cerebral palsy (SCP) was conducted. Method: A multiple treatment design examined the effect of phonetic placement therapy (PPT) and sEMG-facilitated biofeedback relaxation therapy over a 6-week period. Treatment outcomes were measured using acoustic and perceptual analysis. Results: Results revealed significant improvement in single word intelligibility following PPT with the improvements maintained following sEMG treatment. sEMG-facilitated biofeedback relaxation treatment indicated the occurrence of a pre-cursor skill in increased motor control. Intelligibility at paragraph or sentence level did not change following either treatment. Perceptually, there was no change to any parameters of articulation following either treatment. However, subtle changes were observed on acoustic analysis. Functionally, the participant reported no changes to feelings of well-being or distress regarding her speech disorder over the period of intervention. Conclusions: Clinically, the PPT and sEMG treatments demonstrated improvement in single word articulation, despite no perceptible changes to overall intelligibility. It is likely that the severity of the participants dysarthria was a factor in the minimal changes observed following treatment. Future studies examining the treatments in children with mild and/or moderate dysarthria are required. Antecedentes: Se desarrolló un estudio comparativo de modalidades de tratamiento para mejorar la articulación en un niño de 13 años con disartria espástica severa asociada a parálisis cerebral espástica (SCP). Métodos: Se diseño un tratamiento múltiple a través del cual se examinó el efecto de la terapia fonética (PPT) y la terapia de relajación por medio de bioretroalimentación facilitada por electromiografía (sEMG) a lo largo de un periodo de seis semanas. Los resultados del tratamiento fueron medidos utilizando análisis perceptuales y acústicos. Resultados: Los resultados revelaron una mejoría significativa en inteligibilidad de palabras únicas después de la PPT manteniéndose las mejorías después del tratamiento sEMG. El tratamiento de relajación a través de bioretroalimentación facilitada por sEMG indicó la presencia de de una capacidad pre-cursor en el aumento del control motriz. La inteligibilidad a nivel del párrafo o de la oración no cambió después de ambos tratamientos. Perceptualmente no hubo cambios en alguno de los parámetros de la articulación después de ambos tratamientos. Sin embargo hubo cambios mínimos en el análisis acústico. Funcionalmente el participante no reportó cambios en cuanto a la sensación de bienestar o de tensión en relación a la alteración en el habla durante el periodo de la intervención. Conclusiones: Clínicamente los tratamientos con PPT y sEMG mostraron una mejoría en la articulación de palabras únicas, a pesar de no haber cambios perceptibles en general en cuanto a la inteligibilidad. Es posible que la severidad de la disartria del participante fuera un factor determinante en los cambios mínimos que se observaron después del tratamiento. Se requieren estudios a futuro que examinen los tratamientos en niños con disartria leve y/o moderada. Palabras clave: Disartria espástica, bioretroalimentación, sEMG, articulación, alteración en el habla, parálisis cerebral

Speech production in Parkinson's disease: II. Acoustic and electropalatographic investigation of sentence, word and segment durations

Previous investigations employing electropalatography (EPG) have identified articulatory timing deficits in individuals with acquired dysarthria. However, this technology is yet to be applied to the articulatory timing disturbance present in Parkinsons disease (PD). As a result, the current investigation aimed to use EPG to comprehensively examine the temporal aspects of articulation in a group of nine individuals with PD at sentence, word and segment level. This investigation followed on from a prior study (McAuliffe, Ward and Murdoch) and similarly, aimed to compare the results of the participants with PD to a group of aged (n = 7) and young controls (n = 8) to determine if ageing contributed to any articulatory timing deficits observed. Participants were required to read aloud the phrase “I saw a ___ today” with the EPG palate in‐situ. Target words included the consonants /l/, /s/ and /t/ in initial position in both the /i/ and /a/ vowel environments. Perceptual investigation of speech rate was conducted in addition to objective measurement of sentence, word and segment duration. Segment durations included the total segment length and duration of the approach, closure/constriction and release phases of EPG consonant production. Results of the present study revealed impaired speech rate, perceptually, in the group with PD. However, this was not confirmed objectively. Electropalatographic investigation of segment durations indicated that, in general, the group with PD demonstrated segment durations consistent with the control groups. Only one significant difference was noted, with the group with PD exhibiting significantly increased duration of the release phase for /la/ when compared to both the control groups. It is, therefore, possible that EPG failed to detect lingual movement impairment as it does not measure the complete tongue movement towards and away from the hard palate. Furthermore, the contribution of individual variation to the present findings should not be overlooked.

Impact of malocclusion and orthognathic reconstruction surgery on resonance and articulatory function: an examination of variability in five cases

Articulatory patterns and nasal resonance were assessed before and 6 months after orthognathic reconstruction surgery in five patients with dentofacial deformities. Perceptual and physiological assessments showed disorders of nasality and articulatory function preoperatively, two patients being hyponasal, and one hypernasal. Four patients had mild articulatory deficits, and four had reduced maximal lip or tongue pressures. Operation resulted in different patterns of change. Nasality deteriorated in three patients and articulatory precision and intelligibility improved in only one patient and showed no change in the other four. Operation improved interlabial pressures in three patients, while its impact on tongue pressures varied, being improved in one case, deteriorating in one, and remaining unchanged in the other three. The variability in the results highlights the need for routine assessment of speech and resonance before and after orthognathic reconstruction.

Variables associated with communicative participation in Parkinson’s disease and its relationship to measures of health-related quality-of-life

Abstract Purpose: Communication disorders associated with Parkinson’s disease (PD) often lead to restricted participation in life roles, yet there is a limited understanding of influencing factors and few quantitative measurement tools available. This study aimed to identify variables associated with communicative participation in PD and to examine the relationship between the Communicative Participation Item Bank (CPIB) and existing health-related quality-of-life (HRQoL) measures. Method: Self-report data from 378 participants with PD from the US and New Zealand were analysed. Data included responses to the CPIB, PD Questionnaire-8, sub-scales of the Global Health instrument from the Patient Reported Outcomes Measurement Information System (PROMIS) and additional self-report instruments. Result: Greater perceived speech disorder, lower levels of speech usage, fatigue, cognitive and emotional problems and swallowing difficulties were associated with lower levels of communicative participation. Participants’ age significantly influenced findings, interacting with country of residence, sex and speech usage. Scores on the CPIB were moderately correlated with HRQoL measures. Conclusion: Communicative participation in PD is complex and influenced by both demographic and disease-based variables, necessitating a broader view of the communicative experiences of those with PD. Measurement of communicative participation as a separate construct to existing HRQoL measures is recommended.