Acoustic Measures Capture Speech Dysfunction in Spinocerebellar Ataxia

Area of Science:

• Neurology
• Speech-Language Pathology
• Biomedical Engineering

Background:

• Spinocerebellar ataxias (SCA) are hereditary neurodegenerative disorders.
• Dysarthria, characterized by impaired speech production, is a common symptom across SCA types.
• Effective monitoring of speech dysfunction is crucial for managing SCA and guiding therapeutic interventions.

Purpose of the Study:

• To investigate the utility of acoustic measures for objectively assessing speech dysfunction in SCA patients.
• To identify common acoustic indicators of speech impairment across SCA types 1, 2, and 3.
• To evaluate the correlation between acoustic measures and clinical ataxia severity.

Main Methods:

• Speech recordings were obtained from 24 SCA patients and 24 controls during connected speech and sustained vowel tasks.
• Acoustic Voice Quality Index (AVQI) and its sub-metrics (CPPS, HNR, shimmer), jitter, and formant analysis were employed.
• Correlation with the Scale for Assessment and Rating of Ataxia (SARA) speech sub-scores was assessed to evaluate severity tracking.

Main Results:

• AVQI significantly increased in SCA patients compared to controls, serving as a consistent indicator of speech dysfunction.
• Abnormalities in AVQI sub-metrics, increased jitter, and altered formant frequencies (F2, F3, F4) were observed in SCA patients.
• AVQI correlated with SARA speech sub-scores, and CPPS and jitter differentiated between mild and moderate ataxic speech stages.

Conclusions:

• Acoustic measures, particularly AVQI, CPPS, and jitter, objectively quantify speech dysfunction in SCA.
• These acoustic parameters can effectively monitor ataxic speech severity, aiding in disease management.
• The findings support the use of acoustic analysis for objective speech assessment in SCA, informing treatment strategies.