Animals have innate preferences for tastes accompanying calorically rich foods and aversions to tastes associated with potentially spoiled or toxic foods. In addition, they possess learning mechanisms to modify feeding behavior based on their experience. If ingestion of a food is followed by gastrointestinal malaise, animals avoid consuming that food in the future. This phenomenon, known as conditioned taste aversion (CTA), protects animals against repeated consumption of toxic food. Taste aversion learning is considered a type of classical Pavlovian conditioning, where an association is formed between the food (conditioned stimulus [CS]) and subsequent malaise (unconditioned stimulus [US]). To develop a strong CTA, both the food and the malaise must be novel. A remarkable feature of CTA is that the ingestion of food and subsequent visceral malaise can be separated by hours, suggesting that an engram (or memory) of the novel food persists long after initial exposure (Reilly, 2009).