Dysarthria, Stroke
Conditions
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.
Interventions
DEVICEReal tDCS
2mA of tDCS was delivered to the orofacial area of the primary motor cortex (SM1) for 15 minutes. Speech therapy was delivered simultaneously.
DEVICESham tDCS
2mA of tDCS was delivered to the orofacial area of the primary motor cortex (SM1) for 30 sec. Speech therapy was delivered simultaneously.
Sponsors
The Hong Kong Polytechnic University
The University of Hong Kong
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Intervention model description
Double-blinded
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
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.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Acoustic measurement: Harmonic to noise ratio (HNR) | Change before and after tDCS stimulation at immediately post-treatment | Harmonic to noise ratio (HNR) was obtained from sustained vowel phonation. |
| Perceptual speech assessments | 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) | Change before and after tDCS stimulation at immediately post-treatment | Fundamental frequency (F0) was obtained from sustained vowel phonation. |
| Acoustic measurement: Frequency perturbation (jitter %) | Change before and after tDCS stimulation at immediately post-treatment | Frequency perturbation (jitter %) was obtained from sustained vowel phonation. |
| Acoustic measurement: Intensity perturbation (shimmer %) | Change before and after tDCS stimulation at immediately post-treatment | Intensity perturbation (shimmer %) was obtained from sustained vowel phonation. |
| Acoustic measurement: Noise to harmonic ratio (NHR) | Change before and after tDCS stimulation at immediately post-treatment | Noise to harmonic ratio (NHR) was obtained from sustained vowel phonation. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Kinematic measurement: Distance | Change before and after tDCS stimulation at immediately post-treatment | The lip and tongue function during speech production were traced real time and objectively measured using an electromagnetic articulography. All participants were required to produce single-syllable real words of consonant-vowel (CV) construction at high level tone embedded in a carrier phrase and repeat some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/). A custom-written analysis programme was used to annotate and calculate the kinematic measures, including duration (ms), distance (mm), maximum velocity (mm/s), maximum acceleration (m/s2) and maximum deceleration (m/s2) in the approach (movement towards the upper lip/palate) and release (movement away from the upper lip/palate) phases along the z-axis, i.e., along the mid-sagittal plane. |
| Kinematic measurement: Maximum velocity | Change before and after tDCS stimulation at immediately post-treatment | The lip and tongue function during speech production were traced real time and objectively measured using an electromagnetic articulography. All participants were required to produce single-syllable real words of consonant-vowel (CV) construction at high level tone embedded in a carrier phrase and repeat some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/). A custom-written analysis programme was used to annotate and calculate the kinematic measures, including duration (ms), distance (mm), maximum velocity (mm/s), maximum acceleration (m/s2) and maximum deceleration (m/s2) in the approach (movement towards the upper lip/palate) and release (movement away from the upper lip/palate) phases along the z-axis, i.e., along the mid-sagittal plane. |
| Kinematic measurement: Maximum acceleration | Change before and after tDCS stimulation at immediately post-treatment | The lip and tongue function during speech production were traced real time and objectively measured using an electromagnetic articulography. All participants were required to produce single-syllable real words of consonant-vowel (CV) construction at high level tone embedded in a carrier phrase and repeat some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/). A custom-written analysis programme was used to annotate and calculate the kinematic measures, including duration (ms), distance (mm), maximum velocity (mm/s), maximum acceleration (m/s2) and maximum deceleration (m/s2) in the approach (movement towards the upper lip/palate) and release (movement away from the upper lip/palate) phases along the z-axis, i.e., along the mid-sagittal plane. |
| Kinematic measurement: Maximum deceleration | Change before and after tDCS stimulation at immediately post-treatment | The lip and tongue function during speech production were traced real time and objectively measured using an electromagnetic articulography. All participants were required to produce single-syllable real words of consonant-vowel (CV) construction at high level tone embedded in a carrier phrase and repeat some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/). A custom-written analysis programme was used to annotate and calculate the kinematic measures, including duration (ms), distance (mm), maximum velocity (mm/s), maximum acceleration (m/s2) and maximum deceleration (m/s2) in the approach (movement towards the upper lip/palate) and release (movement away from the upper lip/palate) phases along the z-axis, i.e., along the mid-sagittal plane. |
| Kinematic measurement: Duration | Change before and after tDCS stimulation at immediately post-treatment | The lip and tongue function during speech production were traced real time and objectively measured using an electromagnetic articulography. All participants were required to produce single-syllable real words of consonant-vowel (CV) construction at high level tone embedded in a carrier phrase and repeat some syllables (i.e., /pa/, /ta/, /ka/ and /pataka/). A custom-written analysis programme was used to annotate and calculate the kinematic measures, including duration (ms), distance (mm), maximum velocity (mm/s), maximum acceleration (m/s2) and maximum deceleration (m/s2) in the approach (movement towards the upper lip/palate) and release (movement away from the upper lip/palate) phases along the z-axis, i.e., along the mid-sagittal plane. |
Countries
Hong Kong
Outcome results
None listed