The study looks at both obese and lean women. Each woman comes in for two visits. Each woman takes both the Naltrexone or placebo (one during each visit). Research staff and participants are blinded. Drugs are not used as treatment, but rather to provide information for possible future treatments.
Hypotheses are:
1. Compared with their lean counterparts, obese women will demonstrate more fMRI activation in the brain in response to visual food cues.
2. Naltrexone will reduce the activation in reward-relevant brain sites in response to viewing photographs of fattening food as compared in placebo in both groups.
3. Naltrexone will suppress spontaneous intake of food in obese and lean AI women.
