REward SYSTem in Autism Spectrum Disorder and Addictive Disorder

Inclusion Criteria: Arm A ˗ Concerning ASD patients: Adult carrying the diagnosis of ASD (DSM-5, ADOS, ADI-R criteria) Arm B ˗ Concerning FAD patients: Adult diagnosed with FA presenting with food addiction (DSM-5, YFAS 2.0, BES \>= 18 criteria). Arm C ˗ Concerning healthy volunteers : Adult with no neurological and psychiatric history , absence of progressive somatic pathologies or with vital risk. For all participants: * Age greater than or equal to 18 years old * Without intellectual delay (IQ \> 70). * Able to understand and apply the instruction when an active task is proposed, according to the estimate of the investigator. * Free, express, informed and written consent of the participant. * Participant affiliated to a social security scheme Exclusion Criteria: * Neuromotor disorders. * Visual disturbances not corrected or incompatible with MRI. * Known epilepsy. * Current substance use disorder with emotional distress/significant impact on functional outcome * Rare genetic syndrome. * Contraindications to MRI (other than body circumference) * For women of childbearing age: negative urine or blood pregnancy test * Person subject to a measure of judicial protection (safeguard of justice, curatorship, guardianship or family authorization)