What is the Cannon-Bard theory of emotion?
The Cannon-Bard (or Thalamic) theory of emotion is a physiological explanation of emotion developed by Walter Cannon and Philip Bard. Cannon-Bard theory states that we experience emotions and physiological reactions such as sweating, trembling, and muscle tension simultaneously.
More specifically, it suggests that emotions result when the thalamus sends a message to the brain in response to a stimulus, resulting in a physiological reaction.1 For example: I see a snake –> I am afraid, and I begin to tremble.
How the Cannon-Bard Theory Works
According to the Cannon-Bard theory of emotion, we react to a stimulus and experience the associated emotion at the same time. The physical reactions are not dependent upon the emotional reactions, or vice versa.
When an event occurs, the thalamus transmits a signal to the amygdala. The amygdala is a small, oval-shaped structure in the brain that plays an important role in emotional processing, including emotions such as fear and anger. The thalamus also sends signals to the autonomic nervous system, resulting in physical reactions such as muscle tension, shaking, and sweating.
Examples
You can see how the Cannon-Bard theory might be applied by looking at any experience where you have an emotional reaction. While you might immediately think of negative emotional responses, it also applies to positive emotions.
A Frightening Experience
For example, imagine that you are walking to your car through a darkened parking garage. You hear the sounds of footsteps trailing behind you, and spot a shadowy figure slowly following you as you make your way to your car.
According to the Cannon-Bard theory of emotion, you will experience feelings of fear and physical reaction at the same time. You will begin to feel fearful, and your heart will begin to race. You rush to your car, lock the doors behind you, and rush out of the parking garage to head home.
A New Job
Imagine that you are starting a new job. Your first day can be stressful. You’ll be meeting new co-workers, making first impressions, learning more about your role, and participating in training or meetings. Cannon-Bard theory suggests that you would experience both physical and emotional signs of stress simultaneously. You might feel nervous and experience an upset stomach.
A Date
Imagine that you are going on a date with someone you recently met. You really like this person and are excited to spend time with them. You experience both physical and emotional responses, including feelings of happiness and excitement as well as sweaty palms and a rapid heartbeat.
Comparison to Other Theories
The Cannon-Bard theory differs from other theories of emotion such as the James-Lange theory of emotion, which argues that physiological responses occur first and are the cause of emotions.
The James-Lange theory was the dominant theory of emotion at the time, but Harvard physiologist Walter Cannon and his doctoral student Philip Bard felt that the theory did not accurately reflect how emotional experiences take place.
James-Lange Theory
Cannon-Bard theory was formulated as a reaction to the James-Lange theory of emotion. Where James-Lange theory represented a physiological explanation for emotions, the Cannon-Bard theory represents and neurobiological approach.
William James’s theory suggested that people first experience a physiological reaction in response to a stimulus in the environment. People then experience some sort of physiological reaction to this stimulus which is then labeled as an emotion.
For example, if you encounter a growling dog, you might begin to breathe rapidly and tremble. James-Lange theory would then suggest that you would label those feelings as fear.
Cannon’s work instead suggested that emotions could be experienced even when the body does not reveal a physiological reaction. In other cases, he noted, physiological reactions to different emotions can be extremely similar.
People experience sweating, a racing heartbeat, and increased respiration in response to fear, excitement, and anger. These emotions are very different, but the physiological responses are the same.
Cannon and Bard instead suggested that the experience of emotion was not dependent upon interpreting the body’s physiological reactions. Instead, they believed that the emotion and the physical response occur simultaneously and that one was not dependent upon the other.
Schacter-Singer Theory
Another more recent theory is the Schacter-Singer theory of emotion (also known as two-factor) theory, which takes a cognitive approach.
The Schacter-Singer theory draws on elements of both James-Lange theory and Cannon-Bard theory, proposing that physiological arousal occurs first but that such reactions are often similar for different emotions. The theory suggests that the physiological reactions must be cognitively labeled and interpreted as a particular emotion.
The theory emphasizes the role that cognition and elements of the situation play in the experience of emotion.
Criticisms
Criticisms suggest that Cannon-Bard theory places too much emphasis on the role that the thalamus plays in emotions while largely ignoring other parts of the brain. The thalamus is part of the limbic system and does play an important part in the experience of emotions, but more recent research suggests that the process is more complex than the Cannon-Bard theory suggests.2
The basic assumption of Cannon-Bard theory, that physical reactions do not lead to emotions, has been refuted by a number of studies. Research has shown that when people are asked to make a particular facial expression, such as frowning or smiling, they are more likely to also experience an emotion connected to that expression.