Louise Cahill

A pilot study of online assessment of childhood speech disorders

We investigated the feasibility of assessing childhood speech disorders via an Internet-based telehealth system (eREHAB). The equipment provided videoconferencing through a 128 kbit/s Internet link, and enabled the transfer of pre-recorded video and audio data from the participant to the online clinician. Six children (mean age = 5.3 years) with a speech disorder were studied. Assessments of single-word articulation, intelligibility in conversation, and oro-motor structure and function were conducted for each participant, with simultaneous scoring by a face to face and an online clinician. There were high levels of agreement between the two scoring environments for single-word articulation (92%), speech intelligibility (100%) and oro-motor tasks (91%). High levels of inter- and intra-rater agreement were achieved for the online ratings for most measures. The results suggest that an Internet-based assessment protocol has potential for assessing paediatric speech disorders.

Dysarthria in Friedreich’s Ataxia: A Perceptual Analysis

The aims of this study were to: (1) evaluate the perceptual speech dimensions, speech intelligibility and dysarthria severity of a group of individuals diagnosed with Friedreich’s ataxia (FRDA); (2) determine the presence of subgroups within FRDA dysarthria; (3) investigate the relationship between the speech outcome and the clinical factors of disease progression. The study included 38 individuals (21 female, 17 male) with a confirmed diagnosis of FRDA. A group of 20 non-neurologically impaired individuals served as controls. Perceptual analysis, investigating 30 different dimensions of speech, was conducted on a speech sample obtained from each participant. In addition, the Assessment of Intelligibility of Dysarthria Speech was administered. All FRDA participants presented with dysarthria with severities ranging from mild to moderate. Cluster analysis revealed 3 subgroups, the first presenting with mild dysarthric symptoms, the second with increased velopharyngeal involvement and the third characterized by increased laryngeal dysfunction. Dysarthria severity showed a significant correlation to disease duration but to no other clinical measure. The findings support the notion of subgroups in FRDA dysarthria, representing distinct impairments of the speech mechanism and perhaps reflective of differing evolutions beyond the cerebellum.

Higher‐level language deficits resulting from left primary cerebellar lesions

Background: Contemporary neuropsychological studies suggest that cerebellar lesions may impact upon higher‐level cognitive functioning via mechanisms of crossed cerebello‐cerebral diaschisis. Accordingly, right cerebellar lesions have been previously associated with linguistic impairments such as reduced word fluency and agrammatic output. Recently, however, neuroimaging investigations have also identified ipsilateral cerebral hypoperfusion as a consequence of cerebellar lesions, implicating a potential role for the left cerebellum in the mediation of language processes. Aims: The purpose of this research was to investigate the effects of left cerebellar lesions of vascular origin, on general as well as high‐level language skills. Methods & Procedures: Linguistic profiles were compiled for five individuals with left primary cerebellar lesions utilising a comprehensive language test battery. Individual scores relevant to each subtest were compared to a group of non‐neurologically impaired controls. The criterion for anomalous performance was established as ≥ 1.5 SD below the mean of the control group. Outcomes & Results: The findings of this research suggest that higher‐level language deficits may result from left primary cerebellar lesions. All participants demonstrated deficits on measures of word fluency, sentence construction within a set context, producing word definitions, and producing multiple definitions for the same word. Deficits were also noted for several participants on measures of understanding figurative language, forming word associations, identifying and correcting semantic absurdities, and producing synonyms and antonyms. Conclusions: The results presented challenge the notion of a lateralised linguistic cerebellum, supporting a potential role for the left as well as right cerebellar hemispheres in the regulation of language processes, presumably via cerebellar‐basal ganglia/thalamo‐cortical pathways.

Automatic method of pause measurement for normal and dysarthric speech

This study proposes an automatic method for the detection of pauses and identification of pause types in conversational speech for the purpose of measuring the effects of Friedreichs Ataxia (FRDA) on speech. Speech samples of ∼ 3 minutes were recorded from 13 speakers with FRDA and 18 healthy controls. Pauses were measured from the intensity contour and fit with bimodal lognormal distributions using the Expectation-Maximization algorithm in Matlab©. In the speakers with FRDA, both modes in the pause distributions had significantly larger means, with disproportionately fewer pauses associated with the first mode. From this preliminary study, it is concluded that distributional analysis of pause duration holds promise as a useful method of measuring the effects of FRDA on functional speech.

Comparability of Perceptual Analysis of Speech Characteristics in Australian and Swedish Speakers with Multiple Sclerosis

The aims of the present study were to compare the perceptual assessments of deviant speech signs (dysarthria) exhibited by Australian and Swedish speakers with multiple sclerosis (MS) and to explore whether judgements of dysarthria differed depending on whether the speakers and the judges spoke the same or different languages. Ten Australian and 10 Swedish individuals with MS (matched as closely as possible for age, gender, progression type and severity of dysarthria) were assessed by 2 Australian and 2 Swedish clinically experienced judges using a protocol including 33 speech parameters. Results show that the following perceptual dimensions were identified by both pairs of judges in both groups of speakers to a just noticeable or moderate degree: imprecise consonants, inappropriate pitch level, reduced general rate, and glottal fry. The reliability (Spearman rank-order correlation) of the consensus ratings from the Australian and the Swedish judges was high, with a mean rho of 85.7 for the Australian speakers and mean rho of 84.3 for the Swedish speakers. The most difficult perceptual parameters to assess (i.e. to agree on) included harshness, level of pitch and loudness, precision of consonants and general stress pattern. The study indicated that perceptual assessments of speech characteristics in individuals with MS are informative and can be achieved with high inter-judge reliability irrespective of the judge’s knowledge of the speaker’s language.

Perceptual analysis of speech following traumatic brain injury in childhood

Primary objective : To investigate perceptually the speech dimensions, oromotor function, and speech intelligibility of a group of individuals with traumatic brain injury (TBI) acquired in childhood. Research design : The speech of 24 children with TBI was analysed perceptually and compared with that of a group of non-neurologically impaired children matched for age and sex. Main outcome and results : The 16 dysarthric TBI subjects were significantly less intelligible than the control subjects, and demonstrated significant impairment in 12 of the 33 speech dimensions rated. In addition, the eight non-dysarthric TBI subjects were significantly impaired in many areas of oromotor function on the Frenchay Dysarthria Assessment, indicating some degree of pre-clinical speech impairment. Conclusion : The results of the perceptual analysis are discussed in terms of the possible underlying pathophysiological bases of the deviant speech features identified, and the need for a comprehensive instrumental assessment, to more accurately determine the level of breakdown in the speech production mechanism in children following TBI.

Prevalence of speech and/or language impairment in preparatory students in northern Tasmania

The purpose of this paper is to report the prevalence of speech and/or language impairment in a sample of preparatory students in northern Tasmania, Australia. A total of 308 preparatory students attending 30 public schools in northern Tasmania were administered assessments by a speech-language pathologist, and subsequently diagnosed with either typical or impaired speech and/or language skills. Overall, 41.2% of assessed preparatory students were identified as having either speech and/or language impairment. Specifically, 8.7% of students were found to have isolated speech impairment, 18.2% were diagnosed with isolated language impairment, and 14.3% were identified as having comorbid speech and language impairment. Compared to prior Australian and international research, the present data reflect one of the highest prevalence estimates for speech and/or language impairment reported to date. Given the relative paucity of Australian prevalence data, further epidemiological research specifically of Australian children is needed to validate the current findings.

An evaluation of continuous positive airway pressure (CPAP) therapy in the treatment of hypernasality following traumatic brain injury: a report of 3 cases.

Objective:To evaluate the effectiveness of continuous positive airway pressure (CPAP) therapy in the treatment of hypernasality following traumatic brain injury (TBI). Design:An A-B-A experimental research design. Assessments were conducted prior to commencement of the program, midway, immediately posttreatment, and 1 month after completion of the CPAP therapy program. Participants:Three adults with dysarthria and moderate to severe hypernasality subsequent to TBI. Outcome Measures:Perceptual evaluation using the Frenchay Dysarthria Assessment, the Assessment of Intelligibility of Dysarthric Speech, and a speech sample analysis, and instrumental evaluation using the Nasometer. Results:Between assessment periods, varying degrees of improvement in hypernasality and sentence intelligibility were noted. At the 1-month post-CPAP assessment, all 3 participants demonstrated reduced nasalance values, and 2 exhibited increased sentence intelligibility. Conclusions:CPAP may be a valuable treatment of impaired velopharyngeal function in the TBI population.

Articulatory function following traumatic brain injury in childhood: a perceptual and instrumental analysis.

Primary objective: To investigate the articulatory function of a group of children with traumatic brain injury (TBI), using both perceptual and instrumental techniques. Research design: The performance of 24 children with TBI was assessed on a battery of perceptual (Frenchay Dysarthria Assessment, Assessment of Intelligibility of Dysarthric Speech and speech sample analysis) and instrumental (lip and tongue pressure transduction systems) assessments and compared with that of 24 non-neurologically impaired children matched for age and sex. Main outcomes: Perceptual assessment identified consonant and vowel imprecision, increased length of phonemes and overall reduction in speech intelligibility, while instrumental assessment revealed significant impairment in lip and tongue function in the TBI group, with rate and pressure in repetitive lip and tongue tasks particularly impaired. Significant negative correlations were identified between the degree of deviance of perceptual articulatory features and decreased function on many non-speech measures of lip function, as well as maximum tongue pressure and fine force tongue control at 20% of maximum tongue pressure. Additionally, sub-clinical articulatory deficits were identified in the children with TBI who were non-dysarthric. Conclusion: The results of the instrumental assessment of lip and tongue function support the finding of substantial articulatory dysfunction in this group of children following TBI. Hence, remediation of articulatory function should be a therapeutic priority in these children.

Differentiating Profiles of Speech Impairments in Friedreich's Ataxia: A Perceptual and Instrumental Approach.

BACKGROUND The speech disorder associated with Friedreichs ataxia (FRDA) is classically described as ataxic dysarthria. However, variable neuropathology beyond the cerebellum, which may include the corticospinal and corticobulbar tracts, means that the dysarthria can be mixed rather than a pure ataxic dysarthria. AIMS To characterize physiological features of the dysarthria associated with FRDA and identify differential patterns of deviation that may occur across the subsystems of the speech-production mechanism in a series of seven case studies. METHODS & PROCEDURES The assessment battery included a perceptual analysis of a speech sample using an interval rating scale, and a range of instrumental measures to investigate the respiratory, laryngeal, velopharyngeal and articulatory systems. OUTCOMES & RESULTS The results demonstrated the variability that exists in the dysarthria associated with FRDA, highlighting the existence of differential profiles of speech impairment. A particular distinction was observed between the presence of hypernasality and phonatory dysfunction, as evidenced by the instrumental results. CONCLUSIONS & IMPLICATIONS The distinct profiles of dysarthria associated with FRDA indicate that approaches that address multiple subsystems are necessary for the accurate characterization and quantification of the motor speech disorder. Further research is required to investigate the decline in speech function as the disease progresses, as changes in speech function over time may be a good indicator of neurological decline in FRDA.