The proposed project will help to understand the changes in reinforcement and impairment experienced by Roux en Y bariatric surgery (RYGB) patients who consume alcohol. In this study the investigators propose to investigate RYGB patients with a prospective, longitudinal design. Investigators will examine driving impairment before and after surgery as well as study cognitive changes and reinforcement changes that may occur in RYGB patients while consuming alcohol. Finally, investigators aim to better characterize the changes that occur in the pharmacokinetics of alcohol following bariatric surgery and examine key variables which may play a role in the development in alcohol use disorders.

The three major objectives of this NIH sponsored application are: 1) to characterize the severity of cognitive impairment and driving performance changes following alcohol consumption in a group of patients who have undergone Roux-en-Y Gastric Bypass (RYGB) bariatric surgery and 2) to investigate differential reinforcing properties of alcohol in patients before and after they undergo RYGB. Both of these objectives stem from observations from the investigators work and previous empirical studies suggesting that the pharmacokinetics (PK) of alcohol are substantially altered following bariatric surgery. This may lead to alterations in the time-course and severity of alcohol-related cognitive and driving impairment, as well as alter the reinforcing effects of drinking alcohol. Particularly relevant to these objectives, PK data have shown higher peak alcohol concentrations and a shorter time to achieve them in bariatric surgery patients. Therefore the third objective of this application is to better characterize the PK profile of alcohol following RYGB. Finally, investigators will explore whether changes in impairment, reinforcement, and PKs are moderated by gender, age, smoking, and alcohol use.

In this study investigators propose to prospectively investigate approximately 50-60 RYGB patients. Participants will be assessed at baseline (pre-surgery) and one year after surgery (to approximate their weight nadir) in an acute alcohol dosing laboratory paradigm.

Inclusion Criteria:

1. Male or female (approximately 50% each)
2. 21 - 65 years of age
3. In evaluation for Roux-en-Y gastric bypass surgery
4. Able to tolerate alcohol dose
5. Cognitive ability to complete study protocol as assessed at screening
6. Medically stable

Exclusion Criteria:

1. History of or current alcohol use disorder (as assessed at screening)
2. Psychotic or bipolar spectrum disorder (as assessed at screening)
3. Current suicidality (as assessed at screening)
4. Concomitant medication known to significantly interact with alcohol
5. Concomitant medication known to significantly impact driving simulator performance
6. Pregnancy or intending to become pregnant prior to the end of the their participation in the study or breastfeeding
7. Positive urine drug screen
8. Unable to tolerate blood draws
9. Significant risk for developing motion sickness while using the driving simulator
10. Unable to speak English
11. Other factor that would increase participant risk in the protocol in the judgement of the investigators or physician.
12. Participated in an investigational drug study within the past 30 days
13. Is or has an immediate family member that is employeed by the Neuropsychiatric Research Institute
14. Has a pacemaker
15. Insulin dependent diabetes mellitus
16. Smoking defined as regular use of nicotine in the past 6 months
17. A presurgery weight of > 400lbs at screening appointment or as reported on telephone screen
18. Unable to provide a blood sample at the screening appointment or is assessed to have poor vein quality for IV placement as determined by the research clinical personnel.
19. Laboratory abnormalities defined as a hepatic panel greater than three times the upper limit of normal, or fasting glucose of < 60 or >120 mg/dl, or positive pregnancy test.