A Randomized Controlled Trial Study of the Use of Transcranial Direct Current Stimulation (tDCS) in Treating Dysarthria Post-stroke
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- The University of Hong Kong
- Enrollment
- 9
- Locations
- 1
- Primary Endpoint
- Acoustic measurement: Intensity perturbation (shimmer %)
Study Overview
Brief Summary
The proposed study aimed to determine if tDCS can help post-stroke patients with dysarthria.
Detailed Description
A total of 9 Cantonese-speaking chronic post-stroke patients who are suffering from dysarthria was recruited and randomly divided into treatment group and sham group. For the treatment group, an anodal high-definition tDCS of 2 milliampere (mA) lasting for 15 minutes was delivered to the primary motor cortex (SM1) in 10 daily sessions during a 2-week period. For the sham tDCS group, the same setting of tDCS electrodes was applied on the scalp, but the stimulation only lasted for 30 sec in order to cause similar sensation on the scalp as the other group. Simultaneous to the tDCS stimulation, both groups will receive speech and voice therapy for 30 minutes.
An array of outcome measures reflecting speech production ability including acoustic, kinematic, perceptual and self-perceptual qualities was obtained before and after stimulation. It was anticipated that post-stroke dysarthric patients will see improvement in speech production after stimulation. The results provided important insights into the effects of tDCS on articulatory movement in individuals with dysarthria post-stroke.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Double (Participant, Outcomes Assessor)
Eligibility Criteria
- Ages
- 18 Years to 75 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Cantonese-speaking adults
- •At least 6 months after their initial stroke
- •Dysarthria post-stroke
Exclusion Criteria
- •A personal or family history of epilepsy or seizures
- •A history of another neurological condition
- •Speech disorders
- •Voice disorders
- •Oro-maxillo-facial surgery involving the tongue and/or lip
- •Severe cognitive impairment
- •Severe aphasia
- •Heart disease
- •Metallic foreign body implant
- •On medications that lower neural thresholds (e.g. tricyclines, antidepressants, neuroleptic agents, etc.)
Arms & Interventions
Real tDCS
Group 1 (n = 5) received anodal tDCS stimulation and intensive speech and voice therapy; tDCS and speech therapy was applied in 10 daily sessions during a 2-week period, administered on Monday to Friday. The anodal stimulation was delivered to the primary motor cortex (SM1) of the orofacial area.
Intervention: Real tDCS (Device)
Sham tDCS
Group 2 (n = 4) received sham tDCS stimulation and intensive speech and voice therapy. For the sham tDCS group, the same setting of tDCS electrodes was applied on the scalp, but the stimulation only lasted for 30 sec in order to cause a similar sensation on the scalp. tDCS and speech therapy was applied in 10 daily sessions during a 2-week period, administered on Monday to Friday.
Intervention: Sham tDCS (Device)
Outcomes
Primary Outcomes
Acoustic measurement: Intensity perturbation (shimmer %)
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
Intensity perturbation (shimmer %) was obtained from sustained vowel phonation.
Acoustic measurement: Harmonic to noise ratio (HNR)
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
Harmonic to noise ratio (HNR) was obtained from sustained vowel phonation.
Acoustic measurement: Frequency perturbation (jitter %)
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
Frequency perturbation (jitter %) was obtained from sustained vowel phonation.
Acoustic measurement: Noise to harmonic ratio (NHR)
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
Noise to harmonic ratio (NHR) was obtained from sustained vowel phonation.
Perceptual speech assessments
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
All participants were required to produce a sustained vowel /a/, repeated some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/), produce some single words, read a standard paragraph in Cantonese and had a two-minute conversation with the investigator. A professional grade microphone (SM58, Shure, USA) was used to record the speech production. Experienced speech-language pathologists blinded to the neurological condition and history of each participant analyzed the speech samples independently using a perceptual rating scale including 21 speech dimensions covering eight categories, including pitch, loudness, voice quality, resonance, rate, articulation, tone, and general impression. The speech samples were rated using a seven-point equal-appearing interval scale, with a "1" indicating within typical limit performance and a "7" severely deviated from the normal.
Acoustic measurement: Fundamental frequency (F0)
Time Frame: Change before and after tDCS stimulation at immediately post-treatment
Fundamental frequency (F0) was obtained from sustained vowel phonation.
Secondary Outcomes
- Kinematic measurement: Duration(Change before and after tDCS stimulation at immediately post-treatment)
- Kinematic measurement: Maximum deceleration(Change before and after tDCS stimulation at immediately post-treatment)
- Kinematic measurement: Maximum velocity(Change before and after tDCS stimulation at immediately post-treatment)
- Kinematic measurement: Distance(Change before and after tDCS stimulation at immediately post-treatment)
- Kinematic measurement: Maximum acceleration(Change before and after tDCS stimulation at immediately post-treatment)
Investigators
Dr. Lawrence M.W. Ng
Associate Professor
The University of Hong Kong