Psychologists have debated over “what comes first” when we experience extreme emotions. Does our heart rate go up and our sweat start dripping because we are feeling nervous? Or do we start to feel nervous because we are experiencing all of these physical reactions? The Cannon-Bard Theory is one of many theories that attempt to answer this question.
What Is The Cannon-Bard Theory?
The Cannon-Bard Theory says that our emotional and physiological responses occur at the same time, as two separate processes. One is not necessarily caused by the other, but both caused by the same stimulus. It was developed by Walter Cannon and Philip Bard in the 1920s.
Cannon and Bard looked at the brains of different humans and animals who had trouble processing emotion. They discovered that the thalamus played a big role. Their theory laid out the process for how different parts of the brain take in information and respond to it.
How Does the Cannon-Bard Theory Work?
Sensory information goes to the thalamus. The thalamus then sends a message to one of three places: the autonomic nervous system (ANS,) amygdala, or cerebral cortex.
The autonomic nervous system controls the body functions that we do not consciously control. These functions include heart rate, unconscious breathing, sweating, etc. If the ANS gets the “go-ahead” from the thalamus, it will start to ramp up any of these bodily functions.
At the same time, the thalamus may be sending information to the amygdala. This area of the brain controls our emotional responses. If we feel fear, excitement, nervousness, or joy, we can thank the amygdala.
The cerebral cortex controls our conscious thought. This is the part of the brain that will say, “Hey! I guess I feel nervous.” or “Whoa, I’m sweating a lot.”
All of these processes are happening at the same time, and may vary from person to person.
Examples of Cannon-Bard Theory
In yoga and meditation, teachers help their students slow down the breath and calm down the mind. The idea is to counteract the “fight or flight” reflex that we feel in our everyday lives.
The Cannon-Bard Theory says that we simultaneously experience physical and emotional reactions to situations. When the fight or flight reflex is triggered, for example, our heart rate to skyrocket, our palms to sweat, and our mood to go south. But with deep breathing, that reflex goes away. After a few minutes, the body starts to relax and the mood starts to lift. No wonder everyone looks so happy after a yoga class!
The James-Lange Theory
The Cannon-Bard Theory was a direct response to the James-Lange Theory. This was the prevailing theory before Walter Cannon and Philip Bard came around. The James-Lange Theory stated that we experience emotions as a response to psychological reactions in the body.
For example, let’s say you are getting up to speak in front of a class. Your heart starts to pound. Your palms get sweaty. You feel nauseous. According to the James-Lange Theory, this process happens first. Then, we assign an emotion to these sensations. You’re nervous.
Until the 1920s, this was the biggest theory in the study of our emotions. Then Cannon and Bard came around.
Criticism of the James-Lange Theory
Walter Cannon and Philip Bard had a few problems with the James-Lange Theory.
First, there are a lot of psychological responses that don’t necessarily cause emotions. We don’t necessarily feel an emotion every time we need to go to the bathroom, right?
Second, sometimes the same physiological response could cause multiple emotions. Your heart rate may pound because you’re nervous or because you’re excited. You may start to sweat because you’re nervous or just because it’s hot outside, and you don’t have a strong emotional response to the heat.
Cannon and Bard also had a problem with the timing. If bodily responses caused emotional responses, why do our emotions subside faster than our body returns to homeostasis?
With these criticisms in mind, they developed their own theory.
Criticisms Of Cannon-Bard Theory
But this theory isn’t without its critics either. Let’s go back to the idea of yoga and meditation. Practitioners use deep breathing and physical practices to change their emotional state. Similarly, studies have shown that by making certain facial expressions, you can change your emotions.
These studies are often used to critique the Cannon-Bard Theory, arguing that physiological changes do have some sort of impact on our emotions. Theories like the Schachter-Singer Theory attempt to bring the James-Lange Theory and Cannon-Bard Theory together. This theory says that while physical reactions occur before emotions, these reactions may cause different emotions.
How to Remember Different Theories of Emotion
There are a lot of hyphenated names and theories to remember, but memory tricks can help you if you are studying for an exam. Reddit user MickeyEliza had this to say about the Cannon-Bard and Schachter-Singer theories:
“I remember Cannon-Bard by thinking about how if I took a picture (Cannon camera) it would capture both happening at the same time. Then I think about Schachter-Singer by thinking about how you have to THINK while you SING (lyrics, tone, etc.). That’s how I remember that one has cognitive processing of the emotion too. I don’t know how helpful this is but it’s how I remember them 
“
There Is No Right or Wrong Answer…Yet.
The Schachter-Singer Theory was developed over four decades after the Cannon-Bard Theory, yet it’s not the end-all, be-all answer to the study of emotions. There is still a lot of research that needs to be done on the way that we process, recognize, and respond to emotions. But the Cannon-Bard Theory was revolutionary at its time, and remains an important theory in the world of psychology and neurobiology.
