The 'Lombard Effect' in Patients Affected by Adductor Laryngeal Dystonia
- Conditions
- Adductor Spasmodic Dysphonia
- Interventions
- Other: Lombard test
- Registration Number
- NCT06402214
- Brief Summary
Adductory spasmodic dysphonia (AdSD) is a rare condition characterised by irregular and uncontrolled voice interruptions, most commonly affecting women around the age of 45. The diagnosis is clinical and usually requires evaluation by several specialists. The exact cause is not known, but a disturbance of the motor system is hypothesised, probably related to various causes such as loss of cortical inhibition or problems with sensory input.
Neuroimaging studies have shown hyperactivity in various brain regions during speech production in patients with AdSD, but it is still unclear whether this hyperactivity is due to a malfunction of auditory and somatosensory feedback or an impairment of motor programming.
Recent research indicates that patients with AdSD show excessive muscle activation during phonation, probably due to abnormal processing of auditory feedback. This suggests that intervention in the auditory system may offer new treatment opportunities.
The proposed study aims to describe the acoustic, auditory-perceptual and subjective voice and speech changes in AdSD subjects during the Quick-Lombard Test (LT), a test that assesses vocal response under noisy conditions.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 18
- Native Italian-speaking patients;
- Normal hearing, hearing threshold < 20 dB HL for frequencies from 0.5 to 4 KHz;
- Age >18 years and <65 years;
- Written informed consent.
- Non-Italian-speaking patients.
- Patients undergoing treatment for dystonia.
- Previous laryngeal surgery.
- Patient undergoing speech therapy.
- Patient undergoing dopaminergic therapy.
- Inability to sustain phonation of sufficient duration >3 seconds or to perform sufficient tests to assess vocal outcomes.
- Lack of written informed consent.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description Control group Lombard test healthy patients Case group Lombard test patients affected by adductor laryngeal dystonia
- Primary Outcome Measures
Name Time Method Maximum Frequency (Hz) At the time of enrollement The Maximum Frequency (Hz) is the highest frequency recorded within the voice signal
OMNI Vocal Effort Scale At the time of enrollement It is a validated instrument for the assessment of vocal effort perceived by the patient with AdSD. The OMNI-VES is a visual analogue scale 0-10 with graphic representation of vocal effort. The OMNI-VES will be administered under silent conditions and after the LT
Maximum Phonation Time at the time of enrollement The maximum phonatory time (TMF) will be obtained by asking the subject to sustain the vowel /a/ as long as possible in one breath. The longest of the three attempts will be calculated as TMF in seconds. The TMF will be obtained before and during LT.
Maximum Intensity (dB SPL) At the time of enrollement The Maximum Intensity (dB SPL) parameter refers to the highest intensity of the recorded voice signal
Cepstral Peak Prominence-Smoothed (CPPS) At the time of enrollement Cepstral Peak Prominence-Smoothed (CPPS) has been defined as a spectrum of a spectrum, whereby an inverse Fast Fourier Transform of the natural log of a frequency-domain spectrum is applied, transforming the spectrum to the time domain. The cepstral peak (CP) is a representation of the most dominant peak in the cepstrum - normally the fundamental frequency (fo) in a type I signal. After its first applications to voice was established the method of normalizing the amplitude of the overall cepstrum using a linear regression line. When applied to the cepstrum, the level difference (dB) between the cepstral peak and the regression line at the same quefrency provides the cepstral peak prominence (CPP). The CPPS values obtained from speech and vowel tasks proved reliable in predicting overall grade of dysphonia as well as breathiness.
Auditory-perceptual assessment At the time of enrollement Blinded perceptual assessment, using the Global Grading Scale - Hoarseness - Straining - Asthenia - Straining (GRBAS) 0-3 (0 = normal; 1 = mild; 2 = moderate; 3 = severe) will be performed on the recorded voice samples by two speech therapists who will not be involved in the patients' care. Each voice sample will be anonymised and randomly distributed to the assessors.
Average Frequency (Hz) At the time of enrollement The Average Frequency is the fundamental frequency of the voice (pitch) usually ranges from approximately 30-300 Hz, but this varies according to different speakers: typically males' pitch ranges from 50-180Hz and females from 80-250Hz, so we usually set the pitch range to a reasonable range of 50-400Hz for general usage
Degree of Voice Interruptions (%) At the time of enrollement Degree of Voice Interruptions (%) is useful for the evaluation of temporary vocal interruption
Number of Voice Interruptions At the time of enrollement Number of Voice Interruptions is useful for the evaluation of temporary vocal interruption
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
Fondazione Policlinico Universitario A. Gemelli IRCCS
🇮🇹Roma, Italy