Characterization of Auditory Processing Involved in the Encoding of Speech Sounds

Study Overview
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Brief Summary
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The ability to encode the speech signal is determined by ascending and descending auditory processing. Difficulties in processing these speech signals are well described at the behavioral level in a specific language disorder. However, little is known about the underlying pathophysiological mechanisms. The assumption is that we should observe a degradation of the signal provided by the ear in the deaf subject while in case of specific language impairment it would be a phonemic disorder (possibly linked to a processing disorder auditory). The two population groups should therefore have different abnormalities of their central auditory process - which could be modified by the target remediation for each group.

Official Title
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Characterization of Ascending and Descending Auditory Processing Involved in the Encoding of Speech Sounds in Adult and Children: Variability Related to Changes in Sensory Input or a Neurodevelopmental Disorder or Targeted Remediation

Conditions
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Language Impairment, Hearing Loss

Intervention / Treatment
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* Other: E-learning
* Device: Hearing aids fitting


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: For all subjects: native French speaker no medical treatment for behavior or neurological disorders normal or corrected vision right-handed normal otorhinolaryngology examination valid affiliation to social security no participation to another research study For the normal-hearing subjects normal tonal hearing thresholds normal tympanometry For the subjects without specific language impairment aged from 6 ro 40 normal school attendance without scholastic retardation normal intellectual level normal for age reading skills no delayed speech (expression & production) For the children with specific language impairment aged fom 8 to 18 persistent specific literacy difficulties with reading levels at least 18 months behind that of their peers normal intellectual level For the hearing impaired subjects age from 18 to 70 first auditory rehabilitation bilateral and symmetric hearing loss (±10 dB) with hearing thresholds between 0 and 25 dB at 0.25 kilohertz, 0 and 35 dB at 0.5 kilohertz, 0 and 50 dB at 1 kilohertz, 25 and 70 dB at 2 kilohertz, 25 and 80 dB at 3 kilohertz, 30 and 80 dB at 4 kilohertz Exclusion Criteria: non signed assent treatment for depression, epilepsy, Parkinson's or alzheimer's disease during more than 6 months physical health deficiency mental retardation neurological or psychiatric disease incompatible with testing procedure For children known problem of hearing loss or chronic middle ear disease whic compromized the hearing status schooling in a foreign language foreign language spoken at home with both parents

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: 1: Normal hearing children without SLI, transversal group<br>Normal hearing children without Specific Language Impairment (SLI),Transversal group for test-retest measures | |
| No Intervention: 2: Normal hearing children without SLI, longitudinal group<br>Normal hearing children without Specific Language Impairment (SLI), longitudinal group without training | |
| Other: 3: Normal hearing children with SLI, longitudinal group<br>Normal hearing children with Specific Language Impairment (SLI), longitudinal group with training | Other: E-learning<br>* Management of auditory processing disorders with serious game (E-learning)<br>|
| No Intervention: 4: Normal hearing adults without SLI, transversal group<br>Normal hearing adults without Specific Language Impairment (SLI), transversal group for test-retest measures | |
| No Intervention: 5: Normal hearing adults without SLI, longitudinal group<br>Normal hearing adults without Specific Language Impairment (SLI), longitudinal group without hearing aids (HA) | |
| Other: 6: Hearing Impaired candidates for HA, longitudinal group<br>Hearing Impaired adult candidates for hearing aids (HA), longitudinal group with hearing aids (HA) | Device: Hearing aids fitting<br>* Symmetrical hearing loss which are fitted with binaural hearing aids for the first time<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline speech auditory brainstem and late responses (composite and objective measure) in response to syllables (behavioral measure) | Spectro-temporal analysis of speech auditory brainstem and late responses : The speech brainstem and cortical responses are simultaneously obtained in response of different selected syllables from a continuum (selected by using a phonemic identification test) which is presented throughout a behavioral categorical procedure | Arms 2 and 3: Baseline and 5 weeks / Arms 5 and 6: Baseline and 6 months / Arms 1 and 4: Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline medial olivocochlear system (MOCS) functioning measured using the contralateral suppressive effect of transient evoked otoacoustic emissions (composite measure) | Measurement of the contralateral suppressive effect of transient evoked otoacoustic emissions (expressed as Equivalent Attenuation) | Arms 2 and 3: Baseline and 5 weeks / Arms 5 and 6: Baseline and 6 months / Arms 1 and 4: Baseline | 
| Change from Baseline dichotic skills measured using central auditory processing tests (composite measure) | Presentation of different speech material to both ears simultaneously | Arms 2 and 3: Baseline and 5 weeks / Arms 5 and 6: Baseline and 6 months / Arms 1 and 4: Baseline | 
| Change from Baseline speech-noise listening skills measured using logatomes tests (composite measure) | Presentation of disyllabic words in presence of increasing noise levels | Arms 2 and 3: Baseline and 5 weeks / Arms 5 and 6: Baseline and 6 months / Arms 1 and 4: Baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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noise, dyslexia, training, auditory rehabilitation, hearing loss, evoked potentials, dichotic, plasticity