Odorants were delivered with an air-dilution olfactometer as described elsewhere (Kareken et al., 2004; Bragulat et al., 2008; Kareken et al., 2010). The odorant classes were: 1) Alcohol odors (AO, each subject's two most frequently consumed alcoholic drinks, except for vodka, which has little detectable odor), 2) Appetitive control odors (ApCO; chocolate and grape juice; McCormick & Company, Inc., Hunt Valley, MD), and 3) Non-appetitive odors (NApO; International Flavors & Fragrances, Union Beach, NJ), representing stimuli that are not evocative of ingestive thoughts or behavior. As some found certain NApO unpleasant, subjects could choose two of four from: grass, leather, lilac and Douglas fir. AO were actual alcoholic drinks rendered volatile by passing an airstream through the drink's liquid in the olfactometer's odorant vial. NApO and ApCO were chosen according to prior data that showed them to be approximately equal in intensity, pleasantness, and representativeness (Bragulat et al., 2008).
