Have you ever wondered why your dog gets excited when you put on a coat and pick up the keys? What makes kids jump with joy when they hear ice cream truck music?
In the late 19th century, Nobel Prize winner and Russian physiologist, Ivan Pavlov, accidentally discovered what causes these phenomena: Respondent Conditioning.
What is respondent conditioning
Respondent conditioning, also known as classical conditioning, is the learning to respond to a signal in the environment. Respondent conditioning is a form of learning that occurs when a stimulus that naturally elicits a response (known as an unconditioned stimulus) is paired with a stimulus that does not naturally elicit a response (known as a neutral stimulus). After repeated pairings, the neutral stimulus becomes a conditioned stimulus that can elicit the response that was originally elicited by the unconditioned stimulus1.
Five common terms used in conditioning literature are:
- Unconditioned Stimulus (US): A stimulus that can cause a response naturally, also known as a primary stimulus.
- Unconditioned Response (UR): A response that is naturally triggered by US.
- Neutral Stimulus (NS): A stimulus that does not elicit a response before conditioning.
- Conditioned Stimulus (CS): A previously neutral stimulus is now associated with a US to bring about the same UR.
- Conditioned Response (CR): A response triggered by the CS after conditioning.
Pavlov’s famous dog
This classic experiment demonstrates the learning process through respondent conditioning.
Pavlov who was studying his dogs’ digestive processes ended up discovering a new behavior. The dogs would salivate (UR) at the sight or smell of food (US). He then rang a bell (NS) before the dogs would get their food. Slowly, the dogs learned the association between the sound of a bell with the provision of food. Hence, the sound (CS) alone can evoke the behavior of salivation.
The sound of bells forms a learned association with food. Although the dogs would naturally salivate seeing or smelling dog food, they did not salivate at the ringing of a bell, an audio stimulus, prior to this conditioning. After repeated CS-US pairings with the unconditioned stimulus, the neutral stimulus becomes conditioned and it can elicit the behavior of salivation by itself2.
This associative process is therefore also called Pavlovian conditioning.
Respondent conditioning leads to new respondent behavior.
Phases of respondent conditioning
There are three conditioning phases in the respondent conditioning process.
Since conditioning means learning, pre-conditioning means before learning occurs. For that, a certain amount of knowledge or neutral stimuli are naturally present. For example, the dogs naturally salivate (UR) at the sight or smell of dog food (US). They do not need training for that.
Learning occurs when the NS and US are paired together. When the bell sounds and food are presented together, the dogs learn to associate this ringing activity during conditioning with food.
An association between an NS and US starts to form, such that the NS becomes a CS to elicit a CR. The dogs will salivate at the sound of a bell because it has become a conditional response.
Respondent conditioning vs operant conditioning
In psychology, there are two types of conditioning: respondent conditioning and operant conditioning (also called instrumental conditioning).
The key difference between respondent and operant conditioning is whether or not the learned behavior is voluntary. Respondent conditioning results in the learning of involuntary behavior while operant conditioning results in voluntary behavior.
Since involuntary responses cannot be consciously controlled, they are reflex responses3.
Respondent conditioning examples
Our daily lives are filled with examples of respondent conditioning. Here are some common respondent behavior examples.
Every once in a while, a mother bakes cookies, her children’s favorite food before they come home from school. When she does bake, she usually greets them at the door wearing an apron. Over time, the kids learn that Mom wearing an apron (NS) means there are home-based cookies (US). Now, whenever they see her wear an apron after school, they become excited and hungry (CR). Now the sight of apron-wearing becomes a CS.
Bread baking during an open house
A well-known trick used by realtors is to bake bread at open houses. Many people associate the smell of bread baking (NS) with childhood memories (US) of their mother baking bread. As a result, the smell invokes feelings of warmth and homey comfort (CR) and the smell becomes a CS.
Little kids do not like getting an injection because it often results in pain (US) which induces fear (UR). Therefore, hearing words like “needle”, “vaccine”, or “injections” (CS) alone can induce fear (CR) in young children.
Properties of respondent conditioning
Here are some special properties of Pavlovian conditioning.
Higher order conditioning
Second-order conditioning occurs when an unconditioned stimulus is paired with a second stimulus (conditioned stimulus), which is itself paired with a third stimulus (second-order conditioned stimulus) to evoke the same response as the original stimulus.
The degree of learning is generally lower as the associative strength from higher-order conditioning is weaker4.
Stimulus generalization is the process by which a conditioned response is elicited by a stimulus that is similar, but not identical, to the original conditioned stimulus. The similarities between these stimuli allow learning to be generalized from one to the other5.
Fear conditioning, also called aversive conditioning, is a type of learning that occurs when an individual associates a conditioning stimulus with a negative outcome. Vaccination is an example of how the classical conditioning process may result in fear conditioning and phobias6.
Survival used to depend on this kind of associative learning, as it helps us to avoid dangerous situations. However, if the negative response to aversive stimuli is out of proportion to the threat, it may lead to anxiety disorders like phobias7.
Aversive conditioning can have a very powerful effect. Post-traumatic distress disorder (PTSD) can develop from just one traumatic event with a single pairing8.
For instance, fear of seeing blood (hemophobia), fear of closed spaces (claustrophobia), fear of swimming pools (aquaphobia), etc might just be the result of a single CS-US pairing in the past.
Extinction is a conditioning technique where a previously conditioned stimulus no longer invokes the conditioned response. The learned behavior is said to have been extinct.
However, experimental findings show that respondent extinction doesn’t erase the learned behavior. Instead, it generates new learning that inhibits the conditioned response in the conditioning situation9.
- 1.Pear JJ, Eldridge GD. THE OPERANT-RESPONDENT DISTINCTION: FUTURE DIRECTIONS. Journal of the Experimental Analysis of Behavior. Published online November 1984:453-467. doi:10.1901/jeab.1984.42-453
- 2.Rescorla RA. Behavioral Studies of Pavlovian Conditioning. Annu Rev Neurosci. Published online March 1988:329-352. doi:10.1146/annurev.ne.11.030188.001553
- 3.Kirsch I, Lynn SJ, Vigorito M, Miller RR. The role of cognition in classical and operant conditioning. J Clin Psychol. Published online 2004:369-392. doi:10.1002/jclp.10251
- 4.Gewirtz JC, Davis M. Using Pavlovian Higher-Order Conditioning Paradigms to Investigate the Neural Substrates of Emotional Learning and Memory. Learn Mem. Published online September 1, 2000:257-266. doi:10.1101/lm.35200
- 5.Mednick SA, Freedman JL. Stimulus generalization. Psychological Bulletin. Published online 1960:169-200. doi:10.1037/h0041650
- 6.Hermans D, Dirikx T, Vansteenwegenin D, Baeyens F, Van den Bergh O, Eelen P. Reinstatement of fear responses in human aversive conditioning. Behaviour Research and Therapy. Published online April 2005:533-551. doi:10.1016/j.brat.2004.03.013
- 7.Öhman A, Soares JJF. Emotional conditioning to masked stimuli: Expectancies for aversive outcomes following nonrecognized fear-relevant stimuli. Journal of Experimental Psychology: General. Published online 1998:69-82. doi:10.1037/0096-3422.214.171.124
- 8.Rachman S. The conditioning theory of fearacquisition: A critical examination. Behaviour Research and Therapy. Published online 1977:375-387. doi:10.1016/0005-7967(77)90041-9
- 9.Zimmer-Hart CL, Rescorla RA. Extinction of Pavlovian conditioned inhibition. Journal of Comparative and Physiological Psychology. Published online 1974:837-845. doi:10.1037/h0036412