and during testing. Food-restricted mice were given 3–4 g of mouse chow per animal per day depending on weight. To associate the odor of ethanol with the source of food, the piece of Purina chow was placed on the top of a Petri dish with a cotton ball soaked in 20% ethanol. Sixteen holes were made in the top of Petri dish. Thus, animals could sniff the ethanol but could not lick it. Conditioning sessions were carried out every day for 4 d. Every session was ended when the mouse found the piece of food. Weights were monitored each day during food restriction. Buried target testing was performed for 5 d, and the surface target control test was performed twice for one trial per day starting 1 d after the buried target. For the buried-target test, a clean mouse cage was filled with 3 cm of clean bedding. A Petri dish with a cotton ball soaked with 20% ethanol was buried along the perimeter of the cage, approximately 0.5 cm below the bedding so that it was not visible. A mouse was then placed in the center of the cage and the latency to dig up was measured using a
