Serotonin Control of Impulsivity in Tourette Disorder

"A highly selective 5-HT2A receptor ligand (\[18F\]-altanserin) will be injected to patients before each PET scan. The IV injection in the arm (via a catheter) will be performed in continue during a period of 2 hours in the imaging centre (CERMEP) before the acquisition. The dose will be 2,6 MBq/kg +/- 10 % depending the prescription of the nuclear medicine.~Patients will be evaluated twice, one time free of neuroleptic treatment and a second time during stable chronic treatment by neuroleptic."