Development of a Deaf Child With a Cochlear Implant.

Inclusion criteria

To achieve this study, two cohorts will be formed:

• A cohort of deaf children aged 12 to 30 months:

• Be reached a bilateral profound sensorineural hearing loss (greater than 90 dB hearing loss, as classified by the International Bureau for Audiophonology, 1997);
• Raise a cochlear implant;
• Being affiliated to a social security scheme.
• Consent representatives of parental authority (or at least one of the two)
• A cohort of deaf children from 6 to 9 years:

• Be reached a bilateral profound sensorineural hearing loss;
• Be holder of a cochlear implant for at least 3 years;
• Consent representatives of parental authority (or at least one of the two).
• A group of normal hearing typically developing children:

this group will provide benchmarks for perception tests. It consists of two sub-groups:

• Children with normal hearing typically developing 12 to 30 months; children whith a general, linguistic and normal psychomotor evaluated on the basis of prior clinical examination at baseline and on the compilation of their health record. They must not present psychomotor retardation or language.
• Children with normal hearing in typical development 6 to 9 years.

• Be matched in age and sex with deaf children (a pairing with a child on the criteria defined above). In terms of developmental age, we can consider as having comparable in terms of age development of children with:
• +/- 6 months for the population of children 6 to 9 years
• +/- 1 month for the population of children 12 to 30 months.
• Have a typical development, evaluated by a grade level for their age;
• Consent representatives of parental authority (or at least one of the two).

Exclusion criteria

Will be excluded from our study subjects where there is an inability to meet the tests, either in situations:

• Impossible to understand instructions
• Blindness
• Impossible to meet the tests
• Multihandicap
• A legal impossibility. Furthermore, children will be excluded for which there is a refusal on the part of the parents or of the child to participate in the study (for children old enough to express their opinion).