Clinical Trials

Inclusion Criteria: (Minimal or No Alcohol Group)

1. Male or female age 21-70
2. Consume less alcohol than what is described in this protocol as a "higher dose drinker", or consume no alcohol at all
3. Able to complete a 60 min. MRS brain scan

Exclusion Criteria:

1. Inability to speak English
2. Inability or unwillingness to provide written informed consent
3. Diagnosis of active substance dependence other than nicotine (e.g. alcohol, cannabis, caffeine, prescription use of barbiturates, benzodiazepines, opiates, or stimulants) this will be determined using a PRISM (Psychiatric Research Interview for Substance and Mental Disorders) interview
4. Any unstable active medical or additional psychiatric condition as determined by the investigator
5. Active suicidal ideation as determined by the PHQ-9 question 9 indicating response #2 or higher (several days; more than half the days; or nearly every day)
6. History of encephalopathy, hepatic failure, or HIV seropositivity
7. History of claustrophobia
8. History of major head trauma with loss of consciousness >5 minutes or skull fracture
9. History of previous neurological event (e.g. epilepsy, stroke, transient ischemic attack)
10. Implanted metal objects (e.g. pacemakers; aneurysm clips; metal prostheses, joints, rods, or plates)
11. Contraindication to MRI scanning
12. Pregnancy or breast-feeding