Taste aversion is a fascinating psychological and physiological phenomenon that combines an organisms’ biological disposition with classical conditioning. In this case, an organism becomes nauseous, or disgusted even by the smell of a food that they once became ill after eating. The illness does not have to have been due to the food as long as it followed consuming that particular food or drink. This is a version of classical conditioning where the food or drink becomes a conditioned stimulus, that triggers the illness as a conditioned response. Before this occurs, the illness is a natural, unconditioned response to either a virus, or another natural and unconditioned stimulus. I have become very familiar with taste aversion, and can no longer smell cheetos without wanting to throw up. How did such a strange taste aversion occur? One night as a freshman my friends and I decided to see who could eat the most cheetos in a single sitting. (One of us had too many meal ponits). During this time I was feeling slightly unwell and was in the early stages of the Penn State plague. Regardless of this I ate about three family sized bags of cheetos. Later that evening I became quite ill. In this case, the cheetos acted as an unconditioned stimulus that induced an unconditioned response of illness. However, I associated that feeling of illness with the taste of the powdered cheese. This process had made the smell of cheetos into a conditioned stimulus that triggers nausea, a now conditioned response. Note that there were many other stimuli during that evening that I could have associated with my illness, but my biological predisposition for the connection between taste and nausea took precedence.