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Conditioned emotional response (CER)

Conditioned emotional response (CER) refers to the emotional reactions that humans or animals develop in response to external stimuli through associative learning. This process occurs when an individual experiences a stimulus—whether positive or negative—repeatedly in conjunction with certain emotions, leading the brain to form connections between them. Common examples of CER include both joyful anticipations, such as a dog getting excited at the sight of a leash, and negative responses, such as fear of a previously encountered stimulus, like a snake.

The phenomenon of CER is rooted in the brain's functioning, particularly involving the amygdala, which plays a crucial role in emotional regulation and the fight-or-flight response. While these conditioned responses can contribute to phobias or anxieties, they also offer avenues for positive behavioral conditioning. Techniques such as gradual exposure can help recondition emotional responses, allowing individuals to associate previously feared stimuli with non-threatening experiences. Furthermore, CER also informs social interactions and biases, emphasizing the importance of understanding how experiences shape perceptions of others and potentially reinforcing prejudices. By recognizing the impact of CER, individuals can work toward reducing discrimination and fostering more inclusive relationships.

Full Article

A conditioned emotional response (CER) is a feeling that a person or animal has after exposure to some sort of outside stimulus. The response results from experiencing something at the same time, or shortly after, the stimulus enough times that the mind connects the stimulus and the feeling. The American Psychological Association defines a CER as a negative emotional response, which is usually anxiety or fear, induced by a stimulus because of conditioning. While conditioned emotional learning can involve pleasant or unpleasant emotions, the term CER is usually used for learned negative emotional reactions such as fear or anxiety. Hence, CERs are identified as causative factors in many human behaviors, including phobias and many less intense fears. The term CER is often used positively in relation to dogs, and CER training is used to train dogs with behavior issues or major fear responses.

Background

Conditioned responses happen because of the way the brain works. When a person or animal has an experience, the stimuli associated with it travel through the nervous system to the brain. The brain encodes all the stimuli and the body’s responses to them as memories. These memories can be pleasant and positive, such as the way it smelled at home when a favorite meal was cooking, or unpleasant and negative, such as the way the neighborhood smelled after a fire. The brain associates these stimuli with the emotions that accompanied them and stores the memories together. Psychology experts call this conditioning because the body is conditioned, or trained, to interpret the stimuli in a specific way.

The effects of these types of conditioning on human and animal behavior were studied extensively by psychologists beginning in the nineteenth and twentieth centuries. One of the most famous researchers to work with conditioning was Russian physiologist Ivan Pavlov. Pavlov is best known for his experiments that taught dogs to salivate when a bell was rung. He did this by feeding them and ringing the bell at the same time. The dogs salivated when the bell rang because they were eating. Eventually, Pavlov was able to make them salivate at the sound of the bell even when food was not present. This is called classical conditioning. However, in CER, the stimulus triggers a negative emotional response.

For instance, researchers John B. Watson and Rosalie Rayner demonstrated that it was possible to condition people to have negative emotional responses to stimuli in the same way that the dogs were trained to have a physical response. In an experiment that was within the ethical standards of the 1920s but would no longer be permitted, researchers exposed a young baby they called Little Albert to various items, including a white rat, a mask of Santa Claus, and a furry white coat. Initially, the child exhibited only interest and curiosity in the items. However, when the researchers used a hammer and a steel bar to make a loud noise behind Albert’s head at the same time they showed him the white rat, he began to cry and show other signs of fear. Eventually, he displayed what psychologists call generalization when he reacted with fear to any white furry object, including the mask and the coat. The experiment was an unethical but very successful demonstration of CER.

Overview

CERs are examples of associative learning. The response is the result of the brain associating the action or stimuli with the specific negative reaction or emotion. The reactions are usually negative, such as sadness, anxiety, or fear. The negative emotions that result in sadness, stress, and fear are often the result of the body’s fight-or-flight response.

This is an automated response that is controlled and managed in the amygdala. The amygdala is a small area of the brain that serves as a control center for emotions and is also the brain’s alarm system. When something that generates a response of fear or danger is perceived, the amygdala sends out signals that tell the body to prepare to either fight the danger or flee from it. This can happen whether the stimulus is real, such as a snake in a path, or not, such as a picture of a snake.

People and animals can develop CERs to many things that affect all of the senses. For example, feeling panic at the sound of a specific alarm or feeling nauseous at the smell of a specific food after getting sick from it at an earlier instance. The same stimulus can even be both positive and negative, depending on what the person has been conditioned to experience. For instance, someone who is waiting for a check or a letter from a loved one will have a positive response to the sight of the mail truck outside the home, while someone who has many unpaid bills might feel nothing but anxiety at the same sight.

Such conditioned responses are at the root of phobias, the strong fears some people develop about things such as heights, dogs, flying, clowns, and other things. However, the same process that results in CERs can also be used to help alter or extinguish the conditioned response. These fears can be overcome with reason—such as knowing that the snake is just a picture,or that it is not a venomous snake—or by taking advantage of the conditioning process. For instance, a person might be exposed to the snake several times without anything negative happening. This can condition the person’s emotional response to one that is not fearful. The same technique is often used to help eliminate other CERs. For example, a person who is afraid to fly might slowly increase their exposure to planes and flight before planning a trip to somewhere they have always wanted to go. The flight then becomes associated with a pleasant trip, not the previous fears. However, although some fears reduce with this approach, certain persistent phobias might need other evidence-based approaches such as systematic desensitization or cognitive behavioral therapy.

Similarly, conditioning can be used to help improve anxiety and how someone addresses it. While anxiety can be reinforced or created with operant conditioning, the same techniques can be used to help overcome unwarranted fears and negative emotions. A common tool utilized by psychologists is systematic desensitization, where individuals are gradually exposed to the anxiety-inducing stimuli or situations and the exposure is paired with relaxation techniques. Over time, the individual becomes desensitized to the stimuli or situation.

CERs are important because they are a factor in so many aspects of life. In addition to the role they play in everyday experiences, CERs are part of the prejudices and responses individuals have to others. The experiences one individual has with another create the same sort of stimulus-response connections that the brain forms from all other types of stimuli. This means that the type of interaction a person has with a person of another race, religion, or culture can impact future interactions with other people from that same race, religion, or culture. Understanding the role CER plays in relating to others can help minimize or eliminate prejudices or discrimination. 


Bibliography

“Conditioned Emotional Response.” American Psychological Association, 19 Apr. 2018, dictionary.apa.org/conditioned-emotional-response. Accessed 12 Mar. 2026.

“Conditioned Emotional Response.” Psychestudy, 17 Nov. 2017, www.psychestudy.com/behavioral/learning-memory/classical-conditioning/conditioned-emotional-response. Accessed 12 Mar. 2026.

Conger, Anthony J., et al. “Conditioned Emotional Responses in Racial Prejudice.” Ethnic and Racial Studies, vol. 35, no. 2, July 2011, pp. 298–319.

DeAngelis, T. “Little Albert Regains His Identity.” American Psychological Association, vol. 41, no. 1, 2010, www.apa.org/monitor/2010/01/little-albert.aspx. Accessed 12 Mar. 2026.

“Ivan Petrovich Pavlov.” Nobel Prize, www.nobelprize.org/prizes/medicine/1904/pavlov/biographical/. Accessed 12 Mar. 2026.

Kwong, Alex H. K., et al. “Spreading the Reduction of Fear: A Systematic Review on Generalization of Extinction Learning in Human Fear Conditioning.” Clinical Psychology Review, 28 Oct. 2024, DOI:10.31234/osf.io/rbshj. Accessed 13 Mar. 2026.

“The Little Albert Experiment: The Perverse 1920 Study That Made a Baby Afraid of Santa Claus and Bunnies.” Open Culture, 29 Jan. 2015, www.openculture.com/2015/01/the-little-albert-experiment.html. Accessed 12 Mar. 2026.

McLeod, Saul. “Classical Conditioning.” Simply Psychology, 1 Feb. 2024, www.simplypsychology.org/classical-conditioning.html. Accessed 12 Mar. 2026.

O'Bryan, Amanda. "Using Classical Conditioning for Treating Phobias and Disorders." Positive Psychology, 13 July 2023, positivepsychology.com/classical-conditioning-for-phobias/. Accessed 12 Mar. 2026. 

Scatena, Robyn. "Conditioned Emotional Responses in Dogs: Understanding the Science Behind Their Behavior." K9 Mama, 10 July 2024, k9mama.com/k9alchemy/conditioned-emotional-responses-in-dogs-understanding-the-science-behind-their-behavior. Accessed 17 Mar. 2026.

Šimić, Goran et al. “Understanding Emotions: Origins and Roles of the Amygdala.” Biomolecules vol. 11, no. 6, 31 May. 2021, doi:10.3390/biom11060823. Accessed 12 Mar. 2026.

“Understanding the Stress Response.” Harvard Health Publishing, 3 Apr. 2024, www.health.harvard.edu/staying-healthy/understanding-the-stress-response. Accessed 12 Mar. 2026.

Full Article

A conditioned emotional response (CER) is a feeling that a person or animal has after exposure to some sort of outside stimulus. The response results from experiencing something at the same time, or shortly after, the stimulus enough times that the mind connects the stimulus and the feeling. The American Psychological Association defines a CER as a negative emotional response, which is usually anxiety or fear, induced by a stimulus because of conditioning. While conditioned emotional learning can involve pleasant or unpleasant emotions, the term CER is usually used for learned negative emotional reactions such as fear or anxiety. Hence, CERs are identified as causative factors in many human behaviors, including phobias and many less intense fears. The term CER is often used positively in relation to dogs, and CER training is used to train dogs with behavior issues or major fear responses.

Background

Conditioned responses happen because of the way the brain works. When a person or animal has an experience, the stimuli associated with it travel through the nervous system to the brain. The brain encodes all the stimuli and the body’s responses to them as memories. These memories can be pleasant and positive, such as the way it smelled at home when a favorite meal was cooking, or unpleasant and negative, such as the way the neighborhood smelled after a fire. The brain associates these stimuli with the emotions that accompanied them and stores the memories together. Psychology experts call this conditioning because the body is conditioned, or trained, to interpret the stimuli in a specific way.

The effects of these types of conditioning on human and animal behavior were studied extensively by psychologists beginning in the nineteenth and twentieth centuries. One of the most famous researchers to work with conditioning was Russian physiologist Ivan Pavlov. Pavlov is best known for his experiments that taught dogs to salivate when a bell was rung. He did this by feeding them and ringing the bell at the same time. The dogs salivated when the bell rang because they were eating. Eventually, Pavlov was able to make them salivate at the sound of the bell even when food was not present. This is called classical conditioning. However, in CER, the stimulus triggers a negative emotional response.

For instance, researchers John B. Watson and Rosalie Rayner demonstrated that it was possible to condition people to have negative emotional responses to stimuli in the same way that the dogs were trained to have a physical response. In an experiment that was within the ethical standards of the 1920s but would no longer be permitted, researchers exposed a young baby they called Little Albert to various items, including a white rat, a mask of Santa Claus, and a furry white coat. Initially, the child exhibited only interest and curiosity in the items. However, when the researchers used a hammer and a steel bar to make a loud noise behind Albert’s head at the same time they showed him the white rat, he began to cry and show other signs of fear. Eventually, he displayed what psychologists call generalization when he reacted with fear to any white furry object, including the mask and the coat. The experiment was an unethical but very successful demonstration of CER.

Overview

CERs are examples of associative learning. The response is the result of the brain associating the action or stimuli with the specific negative reaction or emotion. The reactions are usually negative, such as sadness, anxiety, or fear. The negative emotions that result in sadness, stress, and fear are often the result of the body’s fight-or-flight response.

This is an automated response that is controlled and managed in the amygdala. The amygdala is a small area of the brain that serves as a control center for emotions and is also the brain’s alarm system. When something that generates a response of fear or danger is perceived, the amygdala sends out signals that tell the body to prepare to either fight the danger or flee from it. This can happen whether the stimulus is real, such as a snake in a path, or not, such as a picture of a snake.

People and animals can develop CERs to many things that affect all of the senses. For example, feeling panic at the sound of a specific alarm or feeling nauseous at the smell of a specific food after getting sick from it at an earlier instance. The same stimulus can even be both positive and negative, depending on what the person has been conditioned to experience. For instance, someone who is waiting for a check or a letter from a loved one will have a positive response to the sight of the mail truck outside the home, while someone who has many unpaid bills might feel nothing but anxiety at the same sight.

Such conditioned responses are at the root of phobias, the strong fears some people develop about things such as heights, dogs, flying, clowns, and other things. However, the same process that results in CERs can also be used to help alter or extinguish the conditioned response. These fears can be overcome with reason—such as knowing that the snake is just a picture,or that it is not a venomous snake—or by taking advantage of the conditioning process. For instance, a person might be exposed to the snake several times without anything negative happening. This can condition the person’s emotional response to one that is not fearful. The same technique is often used to help eliminate other CERs. For example, a person who is afraid to fly might slowly increase their exposure to planes and flight before planning a trip to somewhere they have always wanted to go. The flight then becomes associated with a pleasant trip, not the previous fears. However, although some fears reduce with this approach, certain persistent phobias might need other evidence-based approaches such as systematic desensitization or cognitive behavioral therapy.

Similarly, conditioning can be used to help improve anxiety and how someone addresses it. While anxiety can be reinforced or created with operant conditioning, the same techniques can be used to help overcome unwarranted fears and negative emotions. A common tool utilized by psychologists is systematic desensitization, where individuals are gradually exposed to the anxiety-inducing stimuli or situations and the exposure is paired with relaxation techniques. Over time, the individual becomes desensitized to the stimuli or situation.

CERs are important because they are a factor in so many aspects of life. In addition to the role they play in everyday experiences, CERs are part of the prejudices and responses individuals have to others. The experiences one individual has with another create the same sort of stimulus-response connections that the brain forms from all other types of stimuli. This means that the type of interaction a person has with a person of another race, religion, or culture can impact future interactions with other people from that same race, religion, or culture. Understanding the role CER plays in relating to others can help minimize or eliminate prejudices or discrimination. 


Bibliography

“Conditioned Emotional Response.” American Psychological Association, 19 Apr. 2018, dictionary.apa.org/conditioned-emotional-response. Accessed 12 Mar. 2026.

“Conditioned Emotional Response.” Psychestudy, 17 Nov. 2017, www.psychestudy.com/behavioral/learning-memory/classical-conditioning/conditioned-emotional-response. Accessed 12 Mar. 2026.

Conger, Anthony J., et al. “Conditioned Emotional Responses in Racial Prejudice.” Ethnic and Racial Studies, vol. 35, no. 2, July 2011, pp. 298–319.

DeAngelis, T. “Little Albert Regains His Identity.” American Psychological Association, vol. 41, no. 1, 2010, www.apa.org/monitor/2010/01/little-albert.aspx. Accessed 12 Mar. 2026.

“Ivan Petrovich Pavlov.” Nobel Prize, www.nobelprize.org/prizes/medicine/1904/pavlov/biographical/. Accessed 12 Mar. 2026.

Kwong, Alex H. K., et al. “Spreading the Reduction of Fear: A Systematic Review on Generalization of Extinction Learning in Human Fear Conditioning.” Clinical Psychology Review, 28 Oct. 2024, DOI:10.31234/osf.io/rbshj. Accessed 13 Mar. 2026.

“The Little Albert Experiment: The Perverse 1920 Study That Made a Baby Afraid of Santa Claus and Bunnies.” Open Culture, 29 Jan. 2015, www.openculture.com/2015/01/the-little-albert-experiment.html. Accessed 12 Mar. 2026.

McLeod, Saul. “Classical Conditioning.” Simply Psychology, 1 Feb. 2024, www.simplypsychology.org/classical-conditioning.html. Accessed 12 Mar. 2026.

O'Bryan, Amanda. "Using Classical Conditioning for Treating Phobias and Disorders." Positive Psychology, 13 July 2023, positivepsychology.com/classical-conditioning-for-phobias/. Accessed 12 Mar. 2026. 

Scatena, Robyn. "Conditioned Emotional Responses in Dogs: Understanding the Science Behind Their Behavior." K9 Mama, 10 July 2024, k9mama.com/k9alchemy/conditioned-emotional-responses-in-dogs-understanding-the-science-behind-their-behavior. Accessed 17 Mar. 2026.

Šimić, Goran et al. “Understanding Emotions: Origins and Roles of the Amygdala.” Biomolecules vol. 11, no. 6, 31 May. 2021, doi:10.3390/biom11060823. Accessed 12 Mar. 2026.

“Understanding the Stress Response.” Harvard Health Publishing, 3 Apr. 2024, www.health.harvard.edu/staying-healthy/understanding-the-stress-response. Accessed 12 Mar. 2026.

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