Ketamine and Neurofeedback-Training: Effects on Neuroplasticity in Cocaine Addiction

Inclusion Criteria: * Informed Consent as documented by signature * Male and female cocaine users 18 to 55 years of age * diagnostic and statisical manual (DSM)-5 diagnosis of CUD * Willingness to comply with the study protocol as explained by investigator * Normal level of language comprehension (German or Swiss-German) Exclusion Criteria: * Current or lifetime psychotic disorders * History of severe substance-induced psychosis * Current or lifetime bipolar I or II disorders * Current suicidality * Previous suicide attempts during the last 2 years * Current severe alcohol use disorder * Current severe cannabis use disorder * Current moderate or severe stimulant use disorder (other than cocaine) * Current moderate or severe benzodiazepine use disorder * Current opioid use disorder * First-degree relatives with psychotic disorders * Beck Depression Inventory Score greater than 25 * Unmedicated or unstable hypertension * Severe illness (e. g. myocardial ischemia or arrythmias, severe pulmonary secretions, glaucoma, congestive heart failure or angina, significant renal or hepatic impairment) * Acute infection (e. g. pulmonary or upper respiratory tract infection) * Insufficient treated or uncorrected hyperthyroidism * Severe central nervous system related traumas or disorders (e. g. stroke, cerebral trauma with loss of consciousness over more than 24h, epilepsy) * Increased intracranial pressure * Medication directly affecting glutamate signaling (e. g. anticonvulsant medication) * Any unstable psychoactive medication (no changes in compounds within last 4 weeks before start of study) * Pregnancy or lactation * Women of childbearing potential with no use of medically accepted contraceptive (e. g. condoms, contraceptive diaphragm, birth control pill, hormone injection, intrauterine device) * BMI\>35 * Allergy, hypersensitivity, or other adverse reaction to previous use of ketamine * Contradictions to magnetic resonance imaging * Concurrent participation in other clinical study