For decades it was believed that emotions originated in a single spot in the brain. For example, there is a fingerprint for anger in the brain, because the expression/identification of anger appears to be universal. Based on this scientific premise, the classical theory of emotions was born. The classical theory of emotions poses that emotions are universal and relay a common facial and physical response, across all cultures. For example, when we see someone frowning and are slumped down; we would identify that person as being sad.
It made sense. When you show a large group of people 2 pictures, one is an angry face, the other a happy face, a high proportion of individuals will identify the difference in emotions, whether in Africa, Australia or Canada. Because studies were showing people identifying differences in emotions, it was assumed that there must be an area of the brain that is developed for that particular emotion. That the emotions are somehow built in.
As scientific inquiry continued, a group of scientists started noticing anomalies or outliers in studies and wondered why some people could not identify emotions correctly. So scientists turned to individuals with damage to certain areas of the brain to see if they could express or identify emotions that were associated with that part of the brain. If emotions were built in and there was a fingerprint for that emotion, if that area was damaged it should result in problems with that emotion. So if someone had damage to the amygdale, typically associated with fear, then they would have trouble identifying and expressing fear.
What studies began to show is despite damage to particular brain structures, individuals were still able to express/identify emotions. Why? It turns out that in the event of damage, other areas of the brain have neurons that can take over and serve more than one function. The brain is a wonderful organ with built in redundancy. This means we have extra neurons that are not necessary for that function but are present in case they are needed. It’s like a built in back-up system so if the main program crashes, a secondary program can run. There are actually many areas of the brain that associated with developing the perception and expression of fear.
Also, emotions are not universal. Perception and expression of fear depends a lot on context. There was an interesting study where participants were shown a picture of a facial expression and were asked to identify the emotion. No background was provided to the face in the picture and they were not provided a list of emotions to choose from. They had to self identify what they thought the person was expressing. Their ability to correctly identify the emotion was poor.
However, when the same picture was shown with a background, the accuracy increased. Not surprisingly context plays a much bigger role in identifying emotions than was previously thought. For example, a picture that appears to be an angry person yelling, when put into the context of winning the championship game is not longer angry but ecstatic with happiness/joy for winning.
All sorts of fascinating studies have been done disproving the classical theory of emotions as universal and built in. The new theory of emotions is that it is an emergent property. I spoke of this concept as it relates to pain but feel it would be useful to define again.
An emergent property is when a number of single areas operate within an environment forming a more complex behaviour as a collective (Wikipedia: emergence). For example, there is not just one part of the brain that is associated with the expression of fear. The expression of fear is a collective response of the brain to the environment within the context of the situation and culture norms.
Before the brain expresses fear, it is receiving information from all our senses, our past experiences and our future projections of what the brain thinks will happen. Then the emotion is created from the simultaneous firing of these areas of the brain.
It is amazing how the universe is created and then how we function within this intricate web of experiences. If you like neuroscience and understanding human nature, then you may be interested in the book, How Emotions are Made: The Secret Life of the Brain by Lisa Feldman Barrett.
Written By: Madelaine Golec PT, Pelvic Health Physiotherapist