In recent years, researchers have developed experimental models of oral self-administration of alcohol to study the effects of different variables on alcohol consumption in rats (Linseman, 1987; Tabakoff & Hoffman, 2000). According to Kamenetzky and Mustaca (2005), home cage and operant conditioning models are the two main forms of self-administration of alcohol in animals. The main difference between both models is the behavioral requirement established to have access to alcohol. In two cases the animal controls the temporal pattern of intake and dose.
Delay discounting refers to the process by which a delay between behavior and its consequences diminishes the effectiveness, or “value,” of those consequences. Delay discounting appears to play an important role in a variety of behavior patterns often described as “impulsive” and, thus, this process has received considerable attention recently (see Madden & Bickel, 2010). Non-human animal models have been particularly useful in characterizing delay discounting, and in examining variables that affect impulsive choice. In the basic experimental arrangement with non-human