The Garcia Effect

Explain the theoretical significance of the phenomenon known as the Garcia effect.

Does this phenomenon have any practical significance for animal or human behavior?

The Garcia effect or conditioned taste aversion is an example of classical conditioning of an animal's thought to link a taste with a symptom brought on by toxic substance causing nausea. It has had great significance in the understanding of human and animal learning. It shows that learning has a biological link. It shows that animals and humans learn based on their evolutionary roots. A thought that was snubbed by many early psychologists whom thought that learning had no inbuilt predispositions and that humans were a 'blank slate at birth' (R. E. Cornwell, C. Palme, P. M. Guinther, H. P. Davis, 2005). With nurture rather than nature being the only way a human could be shaped, a view which causes a lot of disagreement in science, coining the phrase 'nature vs. nurture.'

This essay will talk about the significance of the Garcia effect and how it has had a great impact on modern psychological thinking. The basic of this impact showed a strong biological link to learning.

Looking more specifically the Garcia effect is the conditioning of an animal's behaviour to acquire a specific conditioned response (CR) brought on by a specific conditioned stimulus (CS). For example this method is used to train animals to perform certain tasks when they are given the corresponding stimulus. The Garcia effect has also been utilised to condition animals to act in an uncharacteristic way when the stimulus is presented. An example of this is shown when a mouse is fed a grape, then is immediately after given an injection to make it nauseous. The mouse will start to link the grape to becoming nauseous and therefore will refuse the grape whenever it's presented. Although the nauseous feeling isn't linked to the ingestion of the grape the animal will think that it is.

Practically the Garcia effect can have an advantageous affect on people who abuse alcohol. Prescribing them with a pill before they drink alcohol, but will have a negative effect when the person subsequently drinks alcohol, i.e. the person will feel sick, so the result will be that the person will link alcohol to nausea so you can condition people to feel nauseous when they taste alcohol. This technique will eventually condition them to stop drinking alcohol, as they will link alcohol to vomiting. The "taste aversion conditioning, the process by which alcohol aversions are established, is a phylogentically old and highly efficient form of learning" (M. O. Howard, 2001).

This type of conditioning isn't new but it has posed questions into our own psyche, it has shown us that our learning has an evolutionary root. It has shown our ancestors history and what stimuli and response they would have used to learn and survive. It is an example of a phylogenetic trait. A trait that is inbuilt into our consciousness, a result of evolution.

This type of conditioning can be used on animals to further understand their behaviour, which can give us an insight into their past evolutionary learning techniques. Observing animals has shown that there are two basic types of conditioning, one is classical conditioning and the other is instrumental conditioning.

Early studies by Pavlov and Skinner indicated that classical and instrumental learning was free from biological constraints however they are not. A summary of the techniques is written below with their respective biological restraints

In classical learning animals associate one stimulus with the correct response by relating an unconditioned response to a conditioned stimuli. Pavlov (1927) showed that he could make a dog salivate when a bell was rung. A dog naturally salivated when it sees or smells meat. The salivation is the unconditioned response to the meat, which is the unconditioned stimulus. It was then found that you could link the unconditioned response to conditioned stimuli by ringing a bell every time the meat is presented. Then the animal will start linking the bell to the meat and will start to salivated when it hears the bell. The salivation is the conditioned response. However this type of learning is specific to it's evolutionary background, as it should link a noise say a sheep to meat and start to salivate. It wouldn't however link it's shape to meat, as this isn't the way a dog naturally associates food. This theory was shown by 'Brown and Jenkins' (1968) studies of auto-shaping, although in this experiment a pigeon was used, it still relies on the same principals.

Instrumental conditioning shows that animals learn to associate one event to the next. For example a baby will know that if it cries its mother will give it more attention. However there are biological constraints attacked to this type of learning. For example you can instrumentally condition a bird peck (Skinner 1938) if when a light turns on if you give it a reward. But is harder to get to make this link if the response is flapping its wings. It won't associate the reward to the flapping as readily as it does pecking. As it will associate flapping it's wings to an aversive situation in the wild rather than a advantageous situation. This shows that flapping its wings in the wild related to fear as it trying to escape. This is an aversive situation and pecking is associated to eating food a rewarding situation (Brown and Jenkins 1968)

Another type of conditioning is aversive learning. This type of learning is acquired using a combination of instrumental learning and classical learning. This learning links the conditioned stimulus to fear by the use of unconditioned stimuli. So that when the stimulus is presented fear will drive us to avoid the aversive

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