A conditioned stimulus is a stimulus that we learn to respond to with a certain response. It’s the opposite of an unconditioned stimulus which we naturally respond to as part of our physiology.
An example of a conditioned stimulus is a bell for a dogs, which may mean food is coming shortly. The dog learns this because they come to associate the bell with arriving food. For humans, a car horn is also a conditioned stimulus. We’ve learned that we need to get out of the way (that’s our conditioned response) so we don’t get hit!
Generally, a conditioned stimulus has no inherent meaning. It only develops its meaning because of an association we develop between the stimulus and a desired response.
Definition of Conditioned Stimulus
A conditioned stimulus is a previously neutral stimulus that initially has no meaning. We can see it, touch it, and hear it, and it will basically mean nothing to us. However, now that it has become paired with another object that does have meaning, then it begins to have significance.
Russian physiologist Ivan Pavlov discovered that a neutral stimulus that has been repeatedly associated with a meaningful stimulus, will eventually have meaning too.
Food is inherently pleasing; it is an example of an unconditioned stimulus. When the sound of a bell, called a conditioned stimulus, is repeatedly presented before a dog receives food, then the dog will eventually learn that the sound of the bell means that food is coming soon.
The conditioned stimulus (the bell) will trigger a response just as the unconditioned stimulus (food) did before the training.
Conditioned Stimulus Examples
1. The Recess Bell
Stimulus: The recess bell
Response: Students can leave class
Every child sits in class just waiting. Waiting for the sound of the glorious recess bell. That bell means freedom. As soon as it rings it means the kids can escape the classroom and run around like wild animals on the playground. So much fun.
Not only is the recess bell the sound of freedom, it’s also an example of a conditioned stimulus. It really has no inherent meaning. Only until the sound of the bell has been associated with recess does it have any significance.
If we want to use the terminology of classical conditioning, then the sound of the bell is the conditioned stimulus and the joy of recess is the unconditioned stimulus.
2. Rote Learning Math
A conditioned stimulus can also be a simple answer to a math quiz. The stimulus is the math question (2×2) and the response is the learned answer: 4.
In fact, this method of learning – called rote learning – has been the dominant learning style throughout most of history. Teachers teach students what the stimulus is, and what the correct response is, and then repeat until the students manage to develop the association off by heart.
However, critics of this rote learning approach argue that it doesn’t teach students why 2×2 equals 4. So, students don’t get more intelligent. They simply get more knowledgeable and there’s an important difference. Learning why and how math works can help students to multiply different, and bigger, figures than only the ones they have learned by heart through stimulus-and-response.
3. The Bicycle Bell
Stimulus: Bicycle bell
Response: Jump out of the way
Over time, people have learned what the sound of a bicycle bell means; it means you better get out of the way or risk getting hit. The bell on a bicycle serves as a warning to others that a bicycle is approaching.
Generally speaking, the sound of a bell does not inherently mean anything at all initially. It only has meaning because it has been associated with an unconditioned stimulus.
In our example, the unconditioned stimulus is getting hit by a bike. The sound of the bell (CS) takes on meaning by giving us an opportunity to avoid getting hit (UCS). We learn that when we hear the bell, we could get hit by the bike.
4. Learned Phobias
Stimulus: Getting stuck in an elevator
Response: Lifelong fear of elevators
Strictly speaking, a phobia is defined as an irrational fear of a place, object, or situation. Of course, it is better not to use the term “irrational” to someone that has a phobia, because for them, their fear is very real and very reasonable.
However, we can understand how a phobia develops by understanding what a conditioned stimulus is. For example, suppose a person is riding in an elevator and all of a sudden it stops. The person is trapped for several hours. The elevator is small and periodically drops a little and shakes.
Although the person has been rescued with no physical injuries, they develop a fear of elevators and small spaces. The elevator is now a conditioned stimulus because it has been associated with the unconditioned stimulus of nearly crashing.
4. Getting Vaccine Shots
Stimulus: A painful syringe shot
Response: Lifelong fear of syringes
Although the nurse’s syringe looks inherently scary, it’s not. The first time you saw a syringe it did not evoke any kind of emotional response at all. However, as soon as that needle pokes through your epidermal layer and triggers pain, it has become a conditioned stimulus.
Now, every time you see a syringe you will feel a slight tinge of fear. That fear might go a little further. For example, a young child might develop a fear of the doctor’s office. They will start to cry at the first sight of the office, maybe even at first sight of the building when mom pulls the car into the parking lot.
The doctor’s office and the building it is located in have also become conditioned stimuli. This chain of connected conditioned stimuli might extend to going down a specific street on the way to the doctor’s office.
5. Product Packaging
Stimulus: Pleasant-looking packaging
Response: Positive feelings about a brand
Packaging designers put a lot of thought into their designs. Not only are they skilled graphic artists and masters of human-design interaction, but they are also well-versed in the principles of classical conditioning.
A good designer will incorporate features of an stimuli into their design. This might include a beautiful flower, pleasant colors, or even physically attractive models. A lot of times the unconditioned stimulus will have no logical connection to the product at all.
That’s not important. The goal is for the consumer to associate the positive packaging with positive brand recognition. When the consumer sees the package, the positive feelings from those images will automatically be activated and associated with the product.
6. Open House
Stimulus: Freshly baked cookies in an open house
Response: Pleasant feelings about the house
A clever real estate agent has a great intuitive understanding of classical conditioning and the power of association. In addition to making sure the house is clean and looks good, some agents will set some freshly baked bread on the kitchen counters for Open House Day.
When potential buyers enter, the smell of freshly baked bread will naturally trigger a pleasant feeling. Who doesn’t like the aroma of baked goods?
The agent is betting that the house will become associated with the feelings that come from the aroma of freshly baked bread. The house is the conditioned stimulus and the aroma from the bread is the unconditioned stimulus.
7. Animal Predators
Stimulus: A snake sees lots of mice near a house
Response: The snake associates the house with food
There are many lessons that animals learn through the principles of classical conditioning, and the role of the conditioned stimulus can be found in many examples.
When predators are searching for food, they often have to cover a lot of territory. Over time, they will learn that some landscapes are more likely to contain prey than others. Or, there may be certain times of the day in which some prey are out and about, also looking for food.
It may only take on pairing or perhaps repeated associations, but eventually a predator will learn that one area or one time of day produces the best odds of catching a meal. The landscape is the conditioned stimulus and catching prey is the unconditioned stimulus.
8. Changing Your Bicycle Route
Stimulus: An aggressive dog on your bike route
Response: Avoiding that route from now on (aka avoidance learning)
Riding a bicycle is usually a relaxing activity. The whole family can enjoy and a ride in the park or around the neighborhood. Sometimes it’s nice to take a look at other houses and people’s yards.
Unfortunately, some of those well-manicured lawns might also contain a not-so-well-behaved large dog. As soon as you ride past their fence, the dog jumps up and starts barking. It creates a startle response and you nearly crash.
The next time you take the family out for a leisurely ride, everyone gets a little apprehensive as they approach the house with the loud dog. That’s because the objects near the house of the barking dog are now acting as conditioned stimuli. Normally those objects (CS) would not be of any significance, but now they have been associated with the dog’s barking (UCS) and the fear it evokes.
9. Money (Leads to Desire to Work)
Stimulus: Having money allows us to buy food
Response: We work hard to get it
The rectangular shaped paper that we all carry around has no inherent properties. It is just a thin sheet of paper with a bunch of print on it. In and of itself, it means nothing.
Of course, that’s not the full picture. Because that piece of paper can allow us to get things that we want, and need, it takes on significance. A lot of significance. So much significance that we can’t live without it. We need it to buy basic goods, such as food and water.
From a classical conditioning perspective, the piece of paper is the conditioned stimulus. Because it has been associated with the necessities of life, food and water, it has value.
10. Michelin Tires Advertising
Stimulus: A cute baby in a TV ad
Response: Positive feelings toward the brand
One particular Michelin tire commercial is an excellent example of using a conditioned stimulus. The commercial shows a very cute baby sitting in a Michelin tire. The goal is for customers to associate the positive feelings that people naturally have for cute babies with the tire.
A tire in and of itself does not naturally evoke a response. We have to learn something about tires before we will have any feeling towards them. So, by pairing a cute baby (the unconditioned stimulus) with a tire (the conditioned stimulus), the tire company hopes that people will develop a positive feeling for the tire.
This is a very typical strategy in advertising. In fact, it might be hard to find a TV commercial or print ad that does not use classical conditioning to create a response to a conditioned stimulus.
- Positive Reinforcement: When a reward is given to a learner in order to create a positive association between a stimulus and a desired response. A positive reinforcement example is a sticker for good behavior.
- Operant Conditioning: When rewards and punishments are provided to stimulate explicit and intentional (rather than implied) responses to stimuli. An example of operant conditioning is rote learning the times tables until a stimulus (two times two) provides an instant response (four!).
- Stimulus Generalization: When multiple related stimuli lead to the same response. An example of stimulus generalization is when loud bangs stimulate fight or flight responses in war veterans who associate all bangs with wartime danger.
- Response Generalization: When one stimulus leads to multiple possible responses. An example of response generalization is when we respond to “how are you?” in different ways “alright,” “good,” or “fine” but really meaning the same thing.
- Stimulus Discrimination: When you can tell the different between multiple similar stimuli, leading to nuanced differences in responses. A stimulus discrimination example is when a musician can differentiate musical notes by ear.
- Unconditioned Response: When we have a physiological response to a natural stimulus. An unconditioned response example is when you start crying when you see an onion.
- Higher Order Conditioning: When there are two steps in the conditioning process: the unconditioned stimulus is linked to a conditioned stimulus, which is then linked to another conditioned stimulus. The third stimulus causes an unconditioned response associated with the first stimulus, even if the first and third stimulus are not linked.
- Partial Reinforcement: The intermittent rewarding of a behavior in order to prevent extinction.
- Continuous Reinforcement: The continuous reinforcement of a behavior to help shape behavior, meaning the behavior is reinforced every time it occurs.
We can see many examples of the power of the conditioned stimulus in our everyday lives. Advertising incorporates pleasing images that evoke positive feelings into product ads. The power of association also explains how people develop phobias, such as the fear of an elevator or small spaces.
Feeling anxious while approaching a neighbor’s house with a scary dog is an example of a conditioned stimulus warning us that danger is near. In the animal kingdom, the association between food and stimuli such as landscape features or time of day help animals know where and when to hunt for prey.
Perhaps the most powerful conditioned stimulus of all is located right in our wallet or purse. Any guess what that might be?
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