Anticipation Effect on Painful Phenomenons Linked to Rectal Distension for Patients With a Crohn's Disease in Remission

Inclusion Criteria: * For patients : * Patients over 18 years and less than 60 years. * Right-handed. * Diagnosis of Crohn's disease established on clinical biological, endoscopic and anatomopathological criteria. * Ideal localization and/or diarrhea of Crohn's Disease, with an absence of rectal or anoperineal ravages past or presents in order to not do distension on rectal/ and anoperineal lesions. * Crohn's disease treatment authorize : 5-aminosalicylates since at least 4 weeks with a stable dose since at least 2 weeks ; immunosuppressive drugs since at least 12 weeks with a stable dose since at least 4 weeks ; anti-TNF since at least 3 months with a stable dose since at least 1 month ; absence of corticosteroid treatment since at least 15 days. * Clinical remission : Crohn's Disease Activity Index (CDAI) \< 150 (Best 1976) and biological : normal CRP and faecal calprotectin \< 100 g/g. * Patient able to understand and follow necessary commissions for the conduct of the clinical trial, and that have given his free written consent for this study. * Registered to a French social security. * The person won't be allow to participate simultaneously to another study and there won't be an exclusion period to participation to a clinical or therapeutic trial at the end of this study. * For healthy volunteers * Patients over 18 years and less than 60 years. * Right-handed. * Paired with patients for sex and age. * Absence of digestive surgical or medical history except appendectomy, hysterectomy, cholecystectomy, inguinal hernia cure and/or femoral. * Absence of digestive symptomatology searched while a standardized interrogation. * Clinical digestive exam normal. * The person won't be allow to participate simultaneously to another study and there won't be an exclusion period to. participation to a clinical or therapeutic trial at the end of this study. * Registered to a French social security. * Registered to the national file of persons participating to biomedicals searches without direct individual profit. Exclusion Criteria: * Subjet under 18 years and more than 60 years. * Counter-argument for MRI : presence of intra-corporeal ferro-magnetic particles, claustrophobia. * Existence of a severe condition on general level (cardiac, respiratory, hematological, renal, hepatic, cancerous). * Existence of an organic digestive affection (gastritis, gallstones, duodenal ulcer, megacolon, inflammatory colitis). * Existence or history malignant gastrointestinal condition. * History of abdominal digestive surgery except appendectomy, hysterectomy, cure of inguinal hernia) * Recto-anal or périneal active pathology (haemorrhoid , anal fissure …). * Presence of arectal fecal impaction. * Patient included in an other clinical or therapeutic trial. * Patient treated by a drug sensitive to modify sensitivity and/or digestive motor function. * Patient regularly receiving psychotropic drugs (anxiolytics, sedatives, antidepressants, neuroleptics). * Patient with a pathology that could modify visceral sensitivity like diabetes or neurodegenerative diseases. * Persons concerned by articles L1121-5 to L1121-8 of CSP.