Ketamine and Neurofeedback as Combined Therapeutic Interventions to Target Glutamatergic Neurotransmission in Alcohol Use Disorder

Inclusion Criteria: * Informed Consent as documented by signature * In- and outpatients aged 18 to 65 years of all sexes. * DSM-IV diagnosis of alcohol use disorder (mild - severe). * Motivation to reduce or stop alcohol use * Normal level of language comprehension (German or Swiss-German) * Good physical health with no unstable medical conditions * Participants of childbearing potential must use an effective and established method of contraception for the entire study duration * Comply with the study protocol as explained by investigator Exclusion Criteria: * History of DSM-IV severe drug dependence other than alcohol (except for caffeine or nicotine) and any opiod use disorder within two months prior to enrolment. * Hallucinogen and ketamine use 3 months prior to study participation (including regular microdosing). * Alcohol withdrawal symptoms at any of the treatment visits (V2 and V3) (CIWA-Ar Scale \>9). * 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 * High risk of adverse emotional and behavioral reactions * 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) * During the study, new use or dose changes of already existing concomitant medication without prior informing the investigators. * Taking medications that are known to modualte uridine diphosphate glucuronosyltransferase-enzyme * Medication directly affecting glutamate signaling (e. g. anticonvulsant medication) * Inhibitors of UGT1A9 and 1A10 should be discontinued at least five half-lives prior to the administration of ketamine. * Monoamine oxidase and aldehyde or alcohol dehydrogenase inhibitors should be discontinued at least 5 half-lives prior to the dose of ketamine. * 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 \< 17 or \> 35 * Allergy, hypersensitivity, or other adverse reaction to previous use of ketamine * Contradictions to magnetic resonance imaging * Concurrent participation in other clinical study