In Vivo Involvement of the Cholinergic and Dopaminergic Systems in the Pathophysiology of Apathy.

Exclusion Criteria

• •Patients over 75 years old
• •Taking of any pharmacological treatment likely to affect cholinergic systems at the time of PET-scan: Amitriptyline, Atropine, Brompheniramine, Chlorphenamine, Chlorpromazine, Clomipramine, Clozapine, Dimenhydrinate, Diphenhydramine, Doxepine, Hyoscyamine, Imipramine, Meclozine, Nortriptyline, Oxybutynine, Promethazine, Scopolamine, Trimipramine, Hydroxyzine.
• •Taking of any pharmacological treatment likely to affect dopaminergic systems at the time of PET-scan: glucagon, haloperidol, reserpin
• •Taking of any selective serotonine reuptake inhibitors treatment
• •White matter T2 hyperintense lesions (Fazekas score \> 3)
• •NYHA Class III to IV Heart Failure Patient
• •Patients with allergy or conter-indication to entacapone
• •Subjects with positive pregnancy test (BHCG dosage and Urine dipstick), and/or currently breast-feeding
• •Patients unable to come back to hospital for at least 2-follow-up visits
• •Patient with a chronic neurological disorder or severe psychiatric disorder
• •Patient with cognitive impairment (MoCA\<24) and depression (CES-D score \> 17 for men and \>23 for women)
• •Patient presenting a counter-indication for MRI
• •Patient presenting a counter-indication for TEP with \[18F\]-FEOBV or \[18F\]-FDOPA (known allergy)
• •Patient who underwent a PET examination in the previous month
• •Patient with state of health not allowing a displacement in the department of imaging of the CHU: bedridden state, state of health very deteriorated
• •Patient deprived of liberty by judicial or administrative decision
• •Patient under legal protection or unable to express its own consent
• •Subject within exclusion period from another clinical trial