• Race to a Cure Authors

How Does the Brain Give Rise to Emotion?

Everyone has experienced some sort of emotion throughout their life. Whether you are sensitive or indifferent, emotion plays a big role in decision-making and relationships. One could argue that they are the driving force in our lives. Yet, emotions are complex more often than not. People go through situations in which they experience confusing emotions. Sadness and happiness are not detailed enough to describe the emotions that arise during such situations. However, no matter how confusing, simple, or complex emotions or feelings are, they all originate from the same organ, the brain. The most important organ, which has countless vital functions, is also the one that generates our emotions. The process by which emotions come to life is a rather complex process involving thousands of neurotransmitters and parts of the brain, such as the hypothalamus, hippocampus, amygdala, and the limbic cortex.


Image courtesy of Medical News Today.


What Role Does the Limbic System Play?


Neurotransmitters communicate emotions across the limbic system of the brain in response to the things one encounters. The limbic system is made up of various parts such as the hypothalamus, hippocampus, amygdala, and the limbic cortex. Most importantly, it has thousands of neurons. This system helps us understand the emotions we are experiencing by receiving information from neurotransmitters. Neurotransmitters are located in the entire brain, and they help transmit signals to each other and to each part of the brain. The limbic system is then responsible for connecting the experiences we have to certain emotions such as sadness, happiness, fear, or love. However, each part of the limbic system plays a different part in understanding each emotion.



Image courtesy of Teen Brain Talk.

Amygdala


The amygdala is responsible for emotions such as fear. It plays a large role in triggering fight or flight instincts. If a person senses that they are in a dangerous situation, that means their amygdala has helped identify certain factors as a danger. In this way, the amygdala becomes an extremely important part, for it can possibly save one’s life. If it is damaged, it can be hard to understand the dangers of certain situations, and thus, an individual loses fight or flight instincts. This is why the amygdala has been identified as a structure that helps process emotions that arise from environmental factors.


It also stimulates the hypothalamus when emotions such as anger arise. Again, a hormone release is necessary for such an emotion, so the amygdala responds to environmental factors and signals the hypothalamus to respond to the anger.


Hypothalamus


The hypothalamus is the part of the brain that is responsible for sexual responses such as hormone releases and it also helps regulate body temperature in order to maintain homeostasis. The hypothalamus is next in line when it comes to fear and anger. Since it controls hormone releases, the amygdala sends its signals to start releasing adrenaline. Adrenaline is the hormone that is released when one’s fight or flight instincts are initiated. This is yet another vital part of the limbic system that can impair one’s quality of life if it is damaged.


For instance, if you were to get in a car accident and sustain significant brain damage specifically to your amygdala or hypothalamus, you could lose your fight or flight instincts. This can lead to life-threatening situations. Something like a car accident can become a catastrophe if you do not believe that you are in danger. Simpler situations than a car accident can become life-threatening without your fight or flight instincts. Thus, emotions play a significantly large role in our safety as well.


Hippocampus


The hippocampus is the one in charge of memory. It stores memories and identifies the emotions we linked with said situations. It is not often linked with a specific emotion, though it is said to be responsible for recalling past emotions and the memories we correlate with them.


Limbic Cortex


The limbic cortex consists of two other parts of the limbic system, the cingulate gyrus and the parahippocampal gyrus. The limbic system often controls emotions such as happiness. So, it can be said that it is in charge of some of the more positive emotions. However, it is not solely responsible for maintaining happiness, for the precuneus is also involved in sustaining one’s mood and focusing on producing positive thoughts and emotions. According to an online source, “A 2015 study found that people with larger gray matter volume in their right precuneus reported being happier. Experts think the precuneus processes certain information and converts it into feelings of happiness. For example, imagine you’ve spent a wonderful night out with someone you care about. Going forward, when you recall this experience and others like it, you may experience a feeling of happiness.” Yet again, we see that the emotion is extremely complex, for the process of generating emotion often includes various parts of the brain outside of the limbic system.


Love, though often referred to as a happy emotion, is actually one of the emotions generated mainly by the hypothalamus, not the limbic cortex. Love is usually linked to stress and various hormone releases. As discussed earlier, the hypothalamus is in charge of hormone releases. Thus, when someone experiences love, they undergo hormone releases of Dopamine, Oxytocin, Serotonin, and Vasopressin. These are all hormones linked with social interactions, romantic love, and happiness.


Image courtesy of SITN .


Physical Changes and Signs


Emotions are easy to detect because of the physical changes they deploy. Physical changes are especially noticeable when strong emotions such as anger, anxiety, or fear are present. For instance, perhaps you start to get sweaty hands and your heart starts to beat faster when you are in a job interview because you are nervous. Or maybe you have been wronged in some way and you are confronting the person behind it, your heart and breathing rate will increase and your voice could possibly get louder. Though some of the changes are intentional, emotions produce a lot of uncontrollable physical reactions. Either way, both physical and emotional responses to one’s environment originate from the brain.



Article Author: Scarlet Affa

Article Editors: Edie Whittington, Victoria Huang



References

Harikrishnan, N. (2017, April 22). Limbic system. Teen Brain Talk. Retrieved December 20, 2021, from https://teenbraintalk.wordpress.com/limbic-system/.


Sandoiu, A. (2017, February 12). How does our brain process fear? study investigates. Medical News Today. Retrieved December 20, 2021, from https://www.medicalnewstoday.com/articles/315743.


Seladi-Schulman, J. (2018, July 24). What part of the brain controls emotions? fear, happiness, anger, Love. Healthline. Retrieved December 20, 2021, from https://www.healthline.com/health/what-part-of-the-brain-controls-emotions#anger.


Wu, K. (2020, June 19). Love, actually: The science behind lust, attraction, and companionship. Science in the News. Retrieved December 20, 2021, from https://sitn.hms.harvard.edu/flash/2017/love-actually-science-behind-lust-attraction-companionship/.