ACQ Vol 12 no 1 2010

amplification with loud speech to establish the most effective method of communication. The intelligibility of habitual, loud, and amplified speech in five speakers with Parkinson’s disease was assessed by reading 20 sentences under each of the above conditions. These speech samples were then randomised, and listeners were asked to rate the intelligibility of sentences. Acoustic analysis was also performed. Results demonstrated a significant effect for stimulus type, with loud sentences deemed more intelligible than amplified ones, which were in turn more intelligible than the habitual sentences. There were also direct changes observed in phonatory and articulatory behaviour with increased vocal effort. This suggests that increased intensity alone accounts for some, but not all, improvements in intelligibility with vocal effort. In order to determine which phonatory and articulatory changes contribute to better intelligibility ratings, a word transcription task was used to focus on potential phonetic changes. Loud words were transcribed more accurately than amplified words, and amplified words were transcribed more accurately than habitual ones. Overall, the article provides evidence that there are benefits in both loud speech and amplification for dysarthria in Parkinson’s disease. Changes in articulation contribute to increased intelligibility in loud speech. Careful documentation of changes in articulation, resonance, voice quality, and prosody during treatment is recommended to demonstrate how these changes affect listeners, as it appears that other aspects aside from simple loudness need to be addressed. Future research could possibly examine prosody and voice quality more closely. The possibility of any carryover effects to the swallowing mechanism as a result of increased vocal effort would present another relevant opportunity for investigation. Wang, Y., Kent, R., Kent, J., Duffy, J., & Thomas, J. (2009). Acoustic analysis of voice in dysarthria following stroke. Clinical Linguistics and Phonetics , 23(5), 335–347. Kylie Mulcahy As speech pathologists, we understand our clients with dysarthria in a multitude of ways. In those with stroke-related dysarthria, however, the exact profile of underlying involvement is often difficult to demarcate with evidence of laryngeal hypo- and hyper-function existing. This study conducted by reputable authors aims to establish the profile of voice dysfunction in stroke-related dysarthria, using objective instrumental analysis of voice. The authors hypothesised that participants with stroke-related dysarthria would have differing phonatory abilities when compared against young and elderly speakers. A total of 61 individuals (diagnosed with dysarthria following stroke) provided speech samples for analysis, from which 15 acoustic parameters were obtained. These were compared with normative data from previous literature across three gender-split groups (speakers with stroke, healthy elderly speakers, and healthy young speakers). Results indicated that the primary acoustic effect of stroke on both the male and female voice is an increased noise measure (soft phonation index). Although the exact clinical applicability of soft phonation index is unclear, it has been shown to correlate perceptually with various dimensions Acoustic voice analysis in dysarthria following stroke

(including breathiness) and different states of vocal adduction. Generally, the voice acoustic characteristics of speakers with stroke-related dysarthria were similar to those of healthy ageing speakers – a surprising finding. The results from this study suggest that the effects of stroke on the voice are minimal compared to the effects of aging. It is possible, though, that subgroups exist with more serious vocal pathology. The results may therefore be a conservative indication of the degree of impairment, and do not address the concomitant impact on activity and participation in daily living. However, they demonstrate the importance of using a combination of both perceptual and acoustic analysis in the clinical assessment of dysarthria following stroke. Future studies will better enlighten the exact profile of voice dysfunction in this group. Teverovsky, E. G., Bickel, J. O., & Feldman, H. M. (2009). Functional characteristics of children diagnosed with childhood apraxia of speech. Disability and Rehabilitation , 31 (2), 94–102. Lara Lambert Childhood apraxia of speech (CAS) is a severe childhood speech sound disorder with difficulty in sequencing movements required for speech production. In this article the authors show that the International Classification of Functioning Disability and Health – Children and Youth (ICF-CY) can be used as a framework to describe the functional characteristics of children with CAS. A total of 192 parents of 2- to 15-year-old- children with CAS were asked to fill in a survey consisting of 61 items. Apart from questions tapping demographic information, including past or current medical, developmental, and mental health issues, the survey included 43 items based on the World Health Organisation’s systematic description of how young children function in the home and school contexts (i.e., their body functions, performance of daily living activities and social participation). Through descriptive statistics and exploratory factor analysis, four main factors were identified within the broad range of functional problems in children with CAS: 1) cognitive and learning problems included learning through play, literacy (learning to read, spell and write), calculations in numeracy, and memory; 2) social communication difficulties comprised comprehension of verbal and non-verbal messages, undertaking a task, and interpretation of context (including danger), as well as producing a non-verbal message; 3) behavioural dys-regulation encompassed management of behaviour, temperament, and emotions, which influence performance in educational and social environments; 4) other oral motor problems included difficulties with eating and drinking. The authors’ self-critique of limitations of the study include its dependence on parental reports of diagnoses and descriptions and its non-representation of lower socioeconomic families. However, the ICF design on which the study was based has been constructed to minimise cultural and linguistic bias and has been field tested. While speech sound difficulties in young children may resolve, learning and social challenges may persist and the functional analysis using the ICF-CY may be useful for a multidisciplinary team in assessment, intervention, and monitoring of children with CAS. Functional characteristics of children diagnosed with CAS

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ACQ Volume 12, Number 1 2010

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