Previous Page  57 / 60 Next Page
Information
Show Menu
Previous Page 57 / 60 Next Page
Page Background www.speechpathologyaustralia.org.au

ACQ

Volume 12, Number 1 2010

55

(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.

Functional characteristics of children

diagnosed with CAS

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.

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.

Acoustic voice analysis in dysarthria

following stroke

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