Clinical trial NCT02345876: Maturation of Auditory Processing in Children With Dyslexia Compared to Average-reading Children
Official title: Asymmetry, Auditory Processing and Reading Skills in Phonological Dyslexic Children Compared to Average-reading Children
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Dyslexia
Keywords: Dyslexia, Medial olivocochlear system, Maturation, Auditory Processing
Lead sponsor: Hospices Civils de Lyon
Sponsor class: OTHER
First posted: 2015-01-26
Enrollment: 161
Sex: ALL
Minimum age (years): 6
Maximum age (years): 11
Standard ages: CHILD
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: For the dyslexic children: primary care clinic and speech therapists For the normal reading children : elementary schools of Lyon and Clermond-Ferrand and their suburbs

Brief summary: The hypothesis of central auditory processing disorders has been advanced to explain the anomalies of the grapheme/phoneme combination in some dyslexia. These phonological disorders may be linked to abnormalities of the efferent (medial olivocochlear) system modulation and of cortical asymmetry. Indeed, the efferent system has an asymmetry in relation to handedness. Thus, in right-handed subject, it is predominant on the right side. In contrast, in the subject-handed dyslexic, the efferent system tends to be right-lateralized or non-lateralized. However, after an audio-visual training, normal lateralization can appear. This maturation of the efferent system lateralization during reading acquisition seems to have a particular profile in dyslexics with phonological disorder, especially if it is persistent. This finding allows to consider new prognostic evaluation and speech therapy rehabilitation in the dyslexic child.


Eligibility criteria: Common inclusion criteria

* Native French speaker and french education
* No medical treatment for behavior or neurological disorders (as epilepsy)
* Normal or corrected vision
* Right-handed children (Edinburgh tets (Oldfield, 1971): \>+50%)
* Normal ORL examination
* No hearing loss : hearing thresholds not above 15 dB between 250 and 4 000 Hz
* Presence of Otoacoustic Emissions (Total amplitude \< 5 dB or SNR \> 3dB for at least 3 frequency bands between 1 and 4 kHz)
* Normal level of intellectual development
* Regular school attendance

For the normal reading children

* Aged from 6 to less than 11
* Normal reading level

For the dyslexic children

* Aged from 8 to less than 11
* Diagnostic of dyslexia made by a complet check-up during the 6 last months before the inclusion

Exclusion Criteria

* Neurological or psychiatric disease incompatible with the testing procedure
* Ear disease during more than 6 months
* Normal reading children who have repeat a year
* Previous speech therapy for normal reading children
* Not corrected visual acuteness
* Schooling in a foreign language
* Foreign language spoken at home with both parents
* Known hearing deficit
* Invalid social security

Primary outcomes:
measure: Change of The Asymmetry Index of the efferent system at 2 years interval
timeFrame: Day 1 and then at least 2 years (± 4 weeks)
Secondary outcomes:
measure: Change in the level of reading skill
timeFrame: Day 1 and then at least 2 years (± 4 weeks)
measure: Change in the percentage of correct answers obtained during a speech perception test in silence and noise.
timeFrame: Day 1 and then at least 2 years (± 4 weeks)
measure: Change in percentage of correctly repeated stimuli which have been heard in both ears (binaural integration with divided attention) or in one indicated ear (binaural separation with selective attention)
timeFrame: Day 1 and then at least 2 years (± 4 weeks)
Other outcomes:
Locations:
city: Bron
country: France
facility: Centre Hospitzlier Le Vinatier
city: Clermont-Ferrand
country: France
facility: Service ORL CHU Montpied
city: Lyon
country: France
facility: Service d'Audiologie et Explorations Orofaciales Centre de Référence des Troubles des Apprentissages
Study officials:
References: