The major steps forward of the neurosciences in recent years have linked psychiatric diseases, neuropsychological symptoms and brain dysfunctions. The cerebral functioning requiring a big quantity of energy, mitochondria, essential organelles in the cellular energy processes, are at present considered as a way of research for big interest in neurology and in psychiatry. Thus, an increasing number of studies describe potential links between mitochondrial dysfunction and psychiatric symptomatology. The clinical symptomatology of children with mitochondrial cytopathy is varied. Well described neurologically and somatically, it is significantly less in its psychiatric aspects. However, psychiatric symptoms are frequently associated and this symptom has already been described in adult patients. The symptoms mainly include depressive and anxiety disorders, or even tables suggestive of psychotic disorders, which would precede the diagnosis of mitochondrial disease of 13 years on average.

Neuropsychological disorders refer to disorders of the higher functions following a cerebral anomaly (language, praxis, motricity, gnosis, visual spatial processing, memory, attention, intelligence, executive functions ...). Tests validated in French and adapted to children and adolescents can identify neuropsychological disorders in these populations.

Inclusion Criteria:

• Child with mitochondrial cytopathy (defined by the presence of a mutation known to cause mitochondrial cytopathy or mitochondrial respiratory chain abnormality)
• Aged 6 to 17 years
• Beneficiary of a Social Security regime
• Parents sign consent

Exclusion Criteria:

• Child refusal to participate in the study
• Complete inability to complete questionnaires (e.g. non-communicating child)
• Child already included in intervention research modifying care