Apomorphine in Severe Brain-injured Patients

Inclusion Criteria: * 18-80 years old. * Clinically stable, not dependent on medical ventilators for respiration. * Diagnosed as in an unresponsive wakefulness syndrome or minimally conscious state according to the international criteria and based on at least 2 consistent CRS-R in the last 14 days (one CRS-R in the last 7 days). * More than 4 weeks post-insult. * No serious neurological impairments others than related to their acquired brain injury. * No neurological medications other than anti-epileptic or anti-spasticity drugs within the last two weeks. * No use of dopaminergic medications other than apomorphine within the last two weeks. * Informed consent from legal representative of the patient (if patients recover, their consent will also be obtained). Exclusion Criteria: * Use of dopamine agonists or antagonists (e.g. amantadine, bromocriptine, l-dopa, pramipexole, ropinirole, amphetamine, bupropion, methylphenidate / risperidone, haloperidol, chlorpromazine, flupentixol, clozapine, olanzapine, quetiapine) in the last 4 weeks or 4 half-lives of the drug. * Use of drugs with known significant prolongation of the QT interval (e.g. class 1 antiarrythmics, sotalol, macrolides, quinolones, antipsychotic drugs, tricyclic antidepressants. Methadone, chloroquine, quinine) * A corrected QT interval over 480ms (calculated using Bazett's formula on a standard 12-lead ECG recorded in the last 14 days) or other risk factors for arrhythmia (congestive cardiac failure, severe hepatic impairment or significant electrolyte disturbance). * A history of previous neurological functional impairment. * Contraindication to MRI, EEG, or PET (e.g., electronic implanted devices, active epilepsy, external ventricular drain). * Use of nitrates or other vasodilators, central nervous system acting agents such as barbiturates, morphine and related drugs (relative exclusion criterion)