Head tremor is a common symptom in both essential tremor (ET) and cervical dystonia (CD). Distinguishing between these two conditions can be challenging in clinical practice, particularly when head tremor is the dominant feature. Our goal was to explore the potential of speech assessment in recognizing the mechanisms of head tremor in patients with ET and CD. Objective acoustic vocal assessments of oral diadochokinesis, phonatory stability, vocal tremor, and speech timing were performed. Of the 93 patients assessed, 39 had cervical dystonia (CD) with head tremor, 38 had ET with head tremor (ET-HT), and 16 had ET with no head tremor (ET-nHT). Compared to both CD and ET-nHT, ET-HT showed irregular sequential motion rate, excessive pitch fluctuations, increased noise, and higher extent of vocal vibrato. Compared to CD, ET-HT also demonstrated slower sequential motion rate, prolonged pauses, and a slower articulation rate. Additionally, ET-HT had more pronounced vocal tremolo compared to ET-nHT. Speech assessment provided discrimination between the CD and ET-HT groups with an area under curve of 0.80. This study underscores the promising potential of speech analysis in recognizing mechanisms of head tremor in patients with ET or CD, revealing more severe and distinct speech impairments in ET-HT patients compared to those with CD.

• Keywords
• Acoustic analysis, Cervical dystonia, Dysarthria, Essential tremor, Speech disorder,
• Publication type
• Journal Article MeSH

AIM: To investigate the presence and relationship of temporal speech and gait parameters in patients with postural instability/gait disorder (PIGD) and tremor-dominant (TD) motor subtypes of Parkinson's disease (PD). METHODS: Speech samples and instrumented walkway system assessments were acquired from a total of 60 de-novo PD patients (40 in TD and 20 in PIGD subtype) and 40 matched healthy controls. Objective acoustic vocal assessment of seven distinct speech timing dimensions was related to instrumental gait measures including velocity, cadence, and stride length. RESULTS: Compared to controls, PIGD subtype showed greater consonant timing abnormalities by prolonged voice onset time (VOT) while also shorter stride length during both normal walking and dual task, while decreased velocity and cadence only during dual task. Speaking rate was faster in PIGD than TD subtype. In PIGD subtype, prolonged VOT correlated with slower gait velocity (r = -0.56, p = 0.01) and shorter stride length (r = -0.59, p = 0.008) during normal walking, whereas relationships were also found between decreased cadence in dual task and irregular alternating motion rates (r = -0.48, p = 0.04) and prolonged pauses (r = -0.50, p = 0.03). No correlation between speech and gait was detected in TD subtype. CONCLUSION: Our findings suggest that speech and gait rhythm disorder share similar underlying pathomechanisms specific for PIGD subtype.

• Keywords
• Parkinson's disease, dysarthria, gait, postural instability gait difficulty, speech disorder,
• MeSH
• Gait MeSH
• Walking MeSH
• Humans MeSH
• Gait Disorders, Neurologic * etiology   MeSH
• Parkinson Disease * complications   MeSH
• Postural Balance MeSH
• Speech MeSH
• Tremor MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

While speech disorder represents an early and prominent clinical feature of atypical parkinsonian syndromes such as multiple system atrophy (MSA) and progressive supranuclear palsy (PSP), little is known about the sensitivity of speech assessment as a potential diagnostic tool. Speech samples were acquired from 215 subjects, including 25 MSA, 20 PSP, 20 Parkinson's disease participants, and 150 healthy controls. The accurate differential diagnosis of dysarthria subtypes was based on the quantitative acoustic analysis of 26 speech dimensions related to phonation, articulation, prosody, and timing. A semi-supervised weighting-based approach was then applied to find the best feature combinations for separation between PSP and MSA. Dysarthria was perceptible in all PSP and MSA patients and consisted of a combination of hypokinetic, spastic, and ataxic components. Speech features related to respiratory dysfunction, imprecise consonants, monopitch, slow speaking rate, and subharmonics contributed to worse performance in PSP than MSA, whereas phonatory instability, timing abnormalities, and articulatory decay were more distinctive for MSA compared to PSP. The combination of distinct speech patterns via objective acoustic evaluation was able to discriminate between PSP and MSA with very high accuracy of up to 89% as well as between PSP/MSA and PD with up to 87%. Dysarthria severity in MSA/PSP was related to overall disease severity. Speech disorders reflect the differing underlying pathophysiology of tauopathy in PSP and α-synucleinopathy in MSA. Vocal assessment may provide a low-cost alternative screening method to existing subjective clinical assessment and imaging diagnostic approaches.

• Publication type
• Journal Article MeSH