title: Speech acoustic markers of early stage and prodromal Huntington's disease: a marker of disease onset?
abstract: Speech disturbances (e.g., altered prosody) have been described in symptomatic Huntington's Disease (HD) individuals, however, the extent to which speech changes in gene positive pre-manifest (PreHD) individuals is largely unknown. The speech of individuals carrying the mutant HTT gene is a behavioural/motor/cognitive marker demonstrating some potential as an objective indicator of early HD onset and disease progression. Speech samples were acquired from 30 individuals carrying the mutant HTT gene (13 PreHD, 17 early stage HD) and 15 matched controls. Participants read a passage, produced a monologue and said the days of the week. Data were analysed acoustically for measures of timing, frequency and intensity. There was a clear effect of group across most acoustic measures, so that speech performance differed in-line with disease progression. Comparisons across groups revealed significant differences between the control and the early stage HD group on measures of timing (e.g., speech rate). Participants carrying the mutant HTT gene presented with slower rates of speech, took longer to say words and produced greater silences between and within words compared to healthy controls. Importantly, speech rate showed a significant correlation to burden of disease scores. The speech of early stage HD differed significantly from controls. The speech of PreHD, although not reaching significance, tended to lie between the performance of controls and early stage HD. This suggests that changes in speech production appear to be developing prior to diagnosis.
authors.affiliation: Speech Neuroscience Unit, Melbourne Medical School, University of Melbourne, Melbourne, 550 Swanston Street, Melbourne, Victoria 3010, Australia. vogela@unimelb.edu.au
authors.forename: Adam P
authors.initials: AP
authors.lastname: Vogel
authors.forename: Christopher
authors.initials: C
authors.lastname: Shirbin
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Churchyard
authors.forename: Julie C
authors.initials: JC
authors.lastname: Stout
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000235:genetics; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology; D013060:Speech / Q000502:physiology*; D013061:Speech Acoustics; D013997:Time Factors
chemical_list: D015415:Biomarkers; C086055:HTT protein, human; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins