Study of the Role of Top-down Processes in Neuronal Reorganization and Recovery From Sensory Loss: an Exploratory Behavioral and Electroencephalographic Study in Cochlear-supported Deaf Patients

NCT07500909 | Not Yet Recruiting

• 2 other identifiers: RC31/26/00052026-A00163-48
• Study Type: observational
• Target: 90
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study posits that central top-down processes (attention, inhibition), marked by alpha oscillations in EEG, play a key role. Understanding the evolution of these neuronal signatures and their link to pre-implantation visual dependence could allow the identification of biomarkers predictive of the success of auditory rehabilitation.

Conditions

Deafness, Bilateral

Keywords

electroencephalographic; top-down processes; sensory loss; deaf; cochlear implant

Outcome Measures

Primary Outcomes (1)

• Evolution of oscillatory signatures

  Composite criterion :the modulation of alpha oscillations, measured through frequency analysis, amplitude variations and temporal synchronization via EEG, in response to a word recognition task in silence.

  6 months

Secondary Outcomes (5)

• EEG (alpha) signatures and eye-tracking

  6 months

• Speech recognition performance

  6 months

• alpha modulation and memory/auditory

  6 months

• audiovisual, visual and auditory comparison

  6 months

• SSQ

  6 months

Study Arms (5)

Group of cochlear implant patients

This group consists of adult patients with profound bilateral hearing loss, candidates for a first unilateral cochlear implant, and meeting the specific inclusion criteria.

Other: neurophysiological assessment; Behavioral: Cognitive, behavioral and quality of life assessment

Group of young, normally hearing subjects

This control group consists of healthy young adult subjects (18-40 years old) with normal and symmetrical hearing confirmed by audiometry.

Other: neurophysiological assessment; Behavioral: Cognitive, behavioral and quality of life assessment

Group of normally hearing elderly subjects matched for gender and age

This control group consists of healthy older adults (\> 50 years) with age-appropriate hearing (thresholds defined in the inclusion criteria) confirmed by audiometry. They are matched by age (+/- 2 years) and gender with the cochlear implant patient group.

Other: neurophysiological assessment; Behavioral: Cognitive, behavioral and quality of life assessment

Group of experienced cochlear implant patients

This control group consists of adult patients using a unilateral cochlear implant for at least one year and exhibiting good hearing performance (≥70% word recognition).

Other: neurophysiological assessment; Behavioral: Cognitive, behavioral and quality of life assessment

Group of hearing-equipped deaf patients

This control group consists of adult patients with severe bilateral deafness who have been rehabilitated with optimally fitted hearing aids.

Other: neurophysiological assessment; Behavioral: Cognitive, behavioral and quality of life assessment

Interventions

neurophysiological assessment OTHER

Electroencephalography and eye tracking

Group of cochlear implant patients; Group of experienced cochlear implant patients; Group of hearing-equipped deaf patients; Group of normally hearing elderly subjects matched for gender and age; Group of young, normally hearing subjects

Cognitive, behavioral and quality of life assessment BEHAVIORAL

Cognitive anfd behavioral assessment : Speech recognition test in silence (MBAA) and in noise, verbal working memory task with distractors, Trail Making Test and MoCA test. Quality of lige assessment : This questionnaire is a set of scales concerning patients' hearing abilities, experience, and listening skills in different situations. For each question, the patient must answer by choosing a number between 1 (not at all) and 10 (perfectly).

Group of cochlear implant patients; Group of experienced cochlear implant patients; Group of hearing-equipped deaf patients; Group of normally hearing elderly subjects matched for gender and age; Group of young, normally hearing subjects

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants with cochlear implants will be informed about this study during a routine check-up at the partner hearing aid laboratory (Audial), or by the ENT department at Purpan Hospital during a consultation as part of patient follow-up. All participants with normal hearing (young and old) will be recruited through announcements made to members of the ENT department and the CerCo UMR 5549 laboratory.

You may qualify if:

• For cochlear implant patients:
• Adult patients
• Profound bilateral hearing loss requiring a first cochlear implant
• Normal cochlear anatomy (confirmed by preoperative imaging)
• Full insertion of the cochlear electrode array planned
• Acceptance of the protocol and signing of the informed consent form
• Enrollment in a social security or equivalent plan
• For young patients with normal hearing:
• Adult patients aged 18 to 40
• Normal and symmetrical hearing
• Acceptance of the protocol and signature of the informed consent form
• Affiliation with a social security scheme or equivalent
• For older patients with normal hearing:
• Patients over 50 years of age, matched by gender and age (+/- 2 years) with the cochlear implant patient group
• Normal and symmetrical hearing, with hearing thresholds \< 20 dB HL at 2 kHz and \< 40 dB HL at 4 kHz

You may not qualify if:

• History of associated neurological pathology
• Etiologies with unfavorable prognoses, such as recurrent chronic otitis media: These conditions are associated with a poor prognosis due to chronic inflammation that can affect the cochlea
• Duration of profound bilateral deafness exceeding 5 years (worse prognosis)
• Contraindications to EEG or other neurophysiological examinations within the study (for all groups)
• Cognitive impairment confirmed by the MOCA test for the cochlear implant patient group and the group of elderly subjects with normal hearing
• Use of psychotropic medications that may interfere with the results of cognitive or neurological tests
• History of epilepsy or other major neurological disorders
• Pregnancy or breastfeeding
• Participation in another interventional research protocol or one that impacts the criteria studied in this project
• Individuals under legal guardianship (guardianship, tutorship, curatorship, institutionalized, or under a future protection mandate)

Sponsors & Collaborators

• University Hospital, Toulouse: lead
• Centre de recherche Cerveau et Cognition (CERCO): collaborator

MeSH Terms

Conditions

Hearing Loss, Bilateral

Condition Hierarchy (Ancestors)

Hearing Loss; Hearing Disorders; Ear Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Mathieu MARX, PU-PH

  University Hospital, Toulouse

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Mathieu MARX, Pr

CONTACT

05 61 77 77 04; marx.m@chu-toulouse.fr

Florine LEGAY

CONTACT

+33 5 61 77 82 04; legay.f@chu-toulouse.fr

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: PROSPECTIVE
• Target Duration: 6 Months
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 24, 2026
• First Posted: March 30, 2026
• Study Start: March 1, 2026
• Primary Completion (Estimated): March 1, 2029
• Study Completion (Estimated): March 1, 2029
• Last Updated: March 30, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share