Quantitative acoustic measurements for characterization of speech and voice disorders in early untreated Parkinson’s disease

Abstract

An assessment of vocal impairment is presented for separating healthy people from persons with early untreated Parkinson's disease (PD). This study's main purpose was to (a) determine whether voice and speech disorder are present from early stages of PD before starting dopaminergic pharmacotherapy, (b) ascertain the specific characteristics of the PD-related vocal impairment, (c) identify PD-related acoustic signatures for the major part of traditional clinically used measurement methods with respect to their automatic assessment, and (d) design new automatic measurement methods of articulation. The varied speech data were collected from 46 Czech native speakers, 23 with PD. Subsequently, 19 representative measurements were pre-selected, and Wald sequential analysis was then applied to assess the efficiency of each measure and the extent of vocal impairment of each subject. It was found that measurement of the fundamental frequency variations applied to two selected tasks was the best method for separating healthy from PD subjects. On the basis of objective acoustic measures, statistical decision-making theory, and validation from practicing speech therapists, it has been demonstrated that 78% of early untreated PD subjects indicate some form of vocal impairment. The speech defects thus uncovered differ individually in various characteristics including phonation, articulation, and prosody.

Characterisation of voice quality of Parkinson’s disease using differential phonological posterior features

“…Acoustic analysis is widely employed in clinical and research settings, and focuses on analysis of parkinsonian speech that provides objective measures of vocal function, such as fundamental frequency, signal amplitude, jitter, shimmer, noise-to-harmonic ratios, voice onset time and glottal leakage, and last but not least the spectral features such as spectral tilt (J Holmes et al, 2000;Little et al, 2009;Rusz et al, 2011;Bauer et al, 2011). Parkinsonian speech is characterised by higher jitter (more roughness), higher shimmer, descreased pitch range, shorter maximum phonation time and slower diadochokinetic (articulation) rate (Darley et al, 1969).…”

Acoustic Features of Filled Pauses in Polish Task-Oriented Dialogues

“…Their basic descriptions can be found, e.g., in (Farrús et al, 2007) or (Rusz et al, 2011), as well as in Praat Manual. Although the measurements were carried out on a reduced set of preselected, "clean" signals, the number of analysis errors was significant, especially for apq5 and apq11 shimmer.…”

A hybrid model for neurological disordered voice classification using time and frequency domain features

“…[2,5] The voice changes may include changes in the pitch, cycleto-cycle variations; jitter, decrease in amplitude; shimmer, loss of power, addition of noises; harmonic to noise ratios, constriction of voice range; i.e., displacement towards lower frequency. [2,3,6,7] The normal acoustic features lie in the frequency range 20 Hz -4,000 Hz, but the pathological voice features are spread over 20 Hz -20 kHz. The changes in the acoustic features may not be noticeable by normal hearing.…”

“…[2] Hence acoustic analysis of voice to detect voice disorders is gaining more interest in present days. [2][3][4] The acoustic analysis of voice is non invasive, cost effective, comfortable to patients and gives information about the hidden voice disorders. Therefore, the voice measurements are well suited for acoustic analysis with no profound effects of the articulators used during the speech.…”