The Role of Classical Conditioning in Taste Aversions

young boy covering mouth as hand tries to feed him broccoli on fork
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A conditioned taste aversion involves the avoidance of a certain food following a period of illness after consuming that food. These aversions are a great example of how classical conditioning can result in changes in behavior, even after only one incidence of feeling ill.

How Do Conditioned Taste Aversions Work?

Have you ever gotten ill after eating something and later found that just the thought of that food made you feel a bit queasy? This is a great example of what is often referred to as a conditioned taste aversion.

A conditioned taste aversion can occur when eating a substance is followed by illness. For example, if you ate a taco for lunch and then became ill, you might avoid eating tacos in the future even if the food you ate had no relationship to your illness.

While it might seem expected that we would avoid foods that were immediately followed by illness, research has shown that the consumption of the food and the onset of the illness do not need to necessarily occur close together. Conditioned taste aversions can develop even when there is a long delay between the neutral stimulus (eating the food) and the unconditioned stimulus (feeling sick).


Examples of Conditioned Taste Aversion

Imagine that you are on vacation and eat a chicken enchilada at a restaurant. Hours after eating the enchilada, you become violently ill. For years after that incident, you might be unable to bring yourself to eat a chicken enchilada and may even feet queasy when you smell foods that remind you of that particular dish.

This conditioned taste aversion can occur even when you know that your illness is not connected to eating that particular item. In reality, you might be fully aware that you picked up a nasty stomach virus from one of your traveling companions who had been ill just days before the trip.

These conditioned taste aversions are quite common and can last for days to several years. Consider your own aversions to certain foods. Can you link your distaste for particular items to a period of illness, queasiness, or nausea? People may find that they avoid very specific types of food for years simply because they consumed that particular item before they became ill.

Understanding Taste Aversions








Explaining Conditioned Taste Aversions



"Taste aversions do not fit comfortably within the present framework of classical or instrumental conditioning," Garcia noted. " These aversions selectively seek flavors to the exclusion of other stimuli. Interstimulus intervals are a thousand-fold too long."

What Garcia and other researchers were able to demonstrate was that in some cases, the type of neutral stimulus used does have an influence on the conditioning process. So why does the type of stimulus matter so much in this particular case?



A Word From Verywell

Classical conditioning can have a powerful influence on behavior. As conditioned taste aversions so clearly demonstrate, sometimes learning can occur very quickly after only a single-trial.

The next time you find yourself avoiding a particular food, consider the role that a conditioned aversion may have played in your dislike for that particular item.

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Article Sources
  • Garcia, J., Ervin, F.R., & Koelling, R.A. Learning With Prolonged Delay of Reinforcement. Psychonomic Science, 1966; 5: 121-122.

  • Garcia, J. & Koelling, R.A. Relation of Cue to Consequence in Avoidance Learning. Psychonomic Science, 1966; 4: 123-124.

  • Weiten, W. Psychology: Themese and Variations. Belmont, CA: Thompson Wadsworth; 2007.