Huntington's disease is a rare genetic neurodegenerative disease. It is accompanied by movement disorders, cognitive and behavioral. The social behavior of patients are changed, affecting interpersonal relationships. Patients with Huntington's disease are described as self-centered, lacking sympathy and empathy and mentally inflexible. These behavioral problems can be a major source of anxiety for patients and their families. These disorders also have a negative impact cognitive and motor symptoms as well as the functional abilities and the quality of life of patients and their entourage. Authors have suggested that these problems could be related inter alia to social cognition disorders. This concept refers to a set of skills and emotional and social experiences that regulate relations between individuals and can explain the behavior of individuals and groups. The objective is to evaluate disorders of social cognition, which may account for behavioral changes in Huntington's disease.

Inclusion Criteria:

For all particpipants

• Patient gave its written consent
• between 20 and 70 years
• School level : at least 7 years
• native language: french

For presymptomatic patient

• Huntington's disease diagnosed with abnormal number of CAG repeats: 36 < nucleotide expansion (CAG)
• Unified Huntington Disease Rating Scale moteur ≤ 5

For symptomatic patient

• Huntington's disease diagnosed with abnormal number of CAG repeats: 36 < nucleotide expansion (CAG)
• Unified Huntington Disease Rating Scale moteur > 5

Exclusion Criteria:

• No national health insurance affiliation
• Being under guardianship
• Meeting brain MRI exclusion criteria (pacemakers, aneurysm clips, artificial heart valves, ear implants, metal fragments or foreign objects in the eyes, skin, or body, Renal failure, hypersensitivity of Gadolinium) or refusing MRI
• Pregnant or lactating women
• Patient with involuntary movement hampering the realization of MRI