What Is the Cannon-Bard Theory of Emotion? Definition and Overview

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The Cannon-Bard theory of emotion was developed in the 1920s by Walter Cannon and Philip Bard as a response to the James-Lange theory of emotion. According to Cannon, a brain region known as the thalamus is responsible for responding to potentially emotional events.

Key Takeaways: Cannon-Bard Theory

  • The Cannon-Bard theory is a theory of emotions that challenged the influential James-Lange theory.
  • According to Cannon, the brain’s thalamus is crucial for our emotions.
  • Cannon’s research has been influential, although more recent research has led to a more precise understanding of which brain regions are involved in emotions.

Historical Background

In the early 1900s, an influential—yet controversial—theory of emotions was the James-Lange theory, put forward by William James and Carl Lange. According to this theory, our emotions consist of physical changes in the body. (For an example, think of the feelings you might get when you’re nervous, such as your heart beating faster and feeling “butterflies” in your stomach—according to James, our emotional experiences consist of physiological sensations such as these.)

Although this theory was incredibly influential, many researchers doubted some of the claims made by James and Lange. Among those who questioned the James-Lange theory was Walter Cannon, a professor at Harvard.

Key Research

In 1927, Cannon published a landmark paper critiquing the James-Lange theory and suggesting an alternate approach to understanding emotions. According to Cannon, scientific evidence suggested that there were several problems with the James-Lange theory:

  • The James-Lange theory would predict that each emotion involves a slightly different set of physiological responses. However, Cannon noted that different emotions (e.g. fear and anger) can produce very similar physiological states, yet it’s relatively easy for us to tell the difference between these emotions.
  • Cannon noted that many factors affect our physiological states but don’t produce an emotional response. For example, fever, low blood sugar, or being outside in cold weather can produce some of the same bodily changes as emotions (such as having a faster heart rate). However, these types of scenarios don’t typically produce strong emotions. If our physiological systems can be activated without feeling an emotion, Cannon suggested, then something else besides just physiological activation should occur when we feel an emotion.
  • Our emotional responses can occur relatively rapidly (even within a second of perceiving something emotional). However, bodily changes typically occur much more slowly than this. Because bodily changes seem to occur more slowly than our emotions do, Cannon suggested that bodily changes couldn’t be the source of our emotional experience.

Cannon’s Approach to Emotions

According to Cannon, emotional responses and physiological changes in the body occur in response to emotional stimuli—but the two are separate processes. In his research, Cannon sought to identify which part of the brain was responsible for emotional responses, and he concluded that one region in the brain was especially involved in our emotional responses: the thalamus. The thalamus is a region of the brain that has connections to both the peripheral nervous system (the parts of the nervous system outside of the brain and spinal cord) and cerebral cortex (which is involved in the processing of information).

Cannon reviewed studies (including both research with laboratory animals, as well as human patients who had suffered brain damage) suggesting that the thalamus was crucial for experiencing emotions. In Cannon’s view, the thalamus was the part of the brain responsible for emotions, while the cortex was the part of the brain that sometimes suppressed or inhibited emotional responses. According to Cannon, patterns of activity in the thalamus “contribute glow and color to otherwise simply cognitive states.”

Example

Imagine you’re watching a scary movie, and you see a monster jump towards the camera. According to Cannon, this information (seeing and hearing the monster) would be transmitted to the thalamus. The thalamus would then produce both an emotional response (feeling afraid) and a physiological response (racing heartbeat and sweating, for example).

Now imagine you’re trying not to let on that you’ve been scared. You might, for example, try to suppress your emotional reaction by telling yourself that it’s just a movie and the monster is merely a product of special effects. In this case, Cannon would say that your cerebral cortex was responsible for trying to suppress the emotional reaction of the thalamus.

Cannon-Bard Theory vs. Other Theories of Emotion

Another major theory of emotions is the Schachter-Singer theory, which was developed in the 1960s. The Schachter-Singer theory also sought to explain how different emotions can have the same set of physiological responses. However, the Schachter-Singer theory primarily focused on how people interpret the environment around them, rather than focusing on the role of the thalamus.

Newer research on the neurobiology of emotion also allows us to evaluate Cannon’s claim about the role of the thalamus in emotions. While the limbic system (of which the thalamus is one part) is generally considered a key brain region for emotions, more recent research studies have found that emotions involve much more complicated patterns of brain activity than Cannon initially suggested.

Sources and Additional Reading