Change in Reward System Activation and Gut Microbiota Following RYGB and Sleeve Gastrectomy for Weight Loss vs. Control-Heads Up Ancillary

Inclusion Criteria:

Surgical Groups (RYGB and SG) Inclusion criteria for the two surgery groups (n=16)

• Individuals who qualify for Heads Up and would like to participate in this ancillary study
• Be willing to participate in additional procedures including: 4 brains scans (2 before surgery and 2 after surgery), 2 meal challenges (1 before surgery and 1 after surgery), and 2 microbiota collections (1 before surgery and 1 after surgery).
• Be willing to archive microbiota samples

Control Group:

Inclusion Criteria for the BMI matched control group (n=9):

• Males and females age 21-70 years
• Body Mass Index ≥40 kg/m2 without type 2 diabetes or ≥35 kg/m2 and ≤ 60kg/m² with type 2 diabetes
• Agree to receive frequent contacts from investigators and communicate with program staff for up to 6 months
• Able to give written informed consent
• Able to comply with study procedures

Exclusion Criteria:

• Exclusion Criteria for the two surgery groups (n=16):

  • Unable or unwilling to give informed consent
  • Pregnant or planning on becoming pregnant during the 6 months you participate in the study
  • History or presence of unremoveable metal objects (medical or dental) or electronic devices or other contraindication to MRI scanning.
  • Unwillingness to complete an MRI due to confined space or other related phobias

Exclusion Criteria for the BMI matched control group (n=9):

• Unable or unwilling to give informed consent
• Hospitalization for psychiatric illness or substance use/abuse within the past year
• Diagnosis of schizophrenia, other psychotic disorders, bipolar disorder, or personality disorder as determined by the medical staff
• Travel plans that do not permit participation
• Pregnant or planning on becoming pregnant during the 6 months you participate in the study
• History of prior bariatric surgery, extensive bowel resection, or hiatal hernia repair (unless approved by the medical staff)
• History of eating disorder such as anorexia nervosa, bulimia, or binge eating (unless approved by program staff)
• Current major depressive episode or history of suicidal behaviors
• Severe congestive heart failure (NYHA class III, IV)
• Second degree or greater heart block
• Other medical, psychiatric, or behavioral limitations that in the judgement of the investigator may interfere with program participation or the ability to follow the intervention protocol
• History or presence of unremoveable metal objects (medical or dental) or electronic devices or other contraindication to MRI scanning.
• Unwillingness to complete an MRI due to confined space or other related phobias