The Language Environment Analysis (LENA) system is a specific tool for the language environment analysis. Children aged from 18 months to 6 years old, with cochlear implants (CIs), wear an electronic device during a day and their language interactions are registered. Then the investigators can analyze with a specific software four different parameters (adult words, conversational turns, child vocalizations and media exposure) and compare them to the language ability of the children assessed by a speech therapist. With the results, the speech therapist can advise the parents how to improve the language environment to help their children with CIs for their language development. Parents are encouraged to follow these advices at home during few months (5 months +/-1 month). Then there is a new registration of the LENA device and another language assessment are performed, to see if there is any improvement. The investigators also measure the family participation.

Hypothesis : There is an influence of the language environment measured by the LENA system on language development in children with cochlear implants.

Over 24 months the investigators will recruit 90 patients with cochlear implants (CIs) in 2 centers.

Each patient will follow during 5 months and will have three or five visits according to the arm.

Eligibility Criteria:*

Inclusion criteria:

• Congenital profound deaf children
• aged from 18 months to 5 years old 11 months
• with a cochlear implant at least since 6 months
• regular following in speech therapy

Exclusion criteria:

• non-francophone parents
• syndrome (like CHARGE syndrome) or aplasia
• partial insertion of the electrode array
• associated troubles (Autism Spectrum Disorders, mental retardation…)
• visual troubles
• irregular use of the cochlear implant (externe part)
• absence of parental consent