Articulatory Imprecision in Dysarthria Following
Tumour: A Perceptual and Acoustic Investigation
P Cornwell, B Murdoch, E Ward
Imprecise consonant production is a commonly reported perceptual speech features of the dysarthria seen in children treated for cerebellar tumour, however, instrumental studies providing an objective examination of this perceptual feature are scarce. The present study, therefore, employed perceptual and acoustic assessment methods to evaluate the perceptual speech feature of consonant imprecision in three boys (aged 6;6 - 9;8 years) who had undergone treatment for a cerebellar tumour. A group of 10 non-neurologically impaired children served as controls. A comprehensive perceptual profile was compiled using a speech sample analysis, assessment of oromotor function, and single word intelligibility measure. Acoustic analysis, specifically temporal measures, was used to examine consonant production of the alveolar voiceless stop /t/ in word initial position. Deviant perceptual speech characteristics common to all three cases were moderate imprecision of consonants, increased phoneme length, and reduced overall speech intelligibility. Integrity of the lips and tongue on oromotor tasks was found to be compromised, in particular the range and rate of tongue movements, with performance deteriorating with the complexity of the task. Results of the acoustic analysis revealed that the consonant duration measures differed significantly from the control group in all three cases. The present study discusses the links between impaired oromotor function, the timing of lingual gestures and the perception of imprecise consonant production.