Locus Coeruleus and CCHS (Congenital Central Hypoventilation Syndrome)

This study investigates whether cognitive dysfunction in young patients with congenital central hypoventilation syndrome (Ondine Syndrome) is related to the severity of the disease and dysfunction of the locus coeruleus (a brainstem structure involved in autonomic control and cognition). The investigators will assess cognitive evoked potentials (P300 wave) using high-resolution EEG during attention tasks, pupillometry, brain MRI, neuropsychological tests, and heart rate variability. Patients with different severities of PHOX2B gene mutation (alanine expansions \

Inclusion Criteria: * Neonatal diagnosis of Ondine Syndrome. * PARM-type PHOX2B mutation. * Age 7 to 20 years. * Receiving nocturnal ventilation. * Consent obtained. Affiliated with social security. Exclusion Criteria: * Severe autism spectrum disorder preventing test completion. * Legal guardianship or curatorship.