The Neuroscience of Emotions

Oct 17, 2017

anger , anxiety , brain , emotions , love , neuroscience , self

Your brain is the most hungry organ in your body. It requires more oxygen and nutrients than any other, and the complex neural networks that make it up largely explain everything you do, every day. Advances in neuroscience have improved our understanding of complex emotions and behaviours, providing valuable information that we can implement into our daily lives.

If asked what makes you human, emotions - or some aspect of your personality intrinsically linked to emotions - might come pretty close to the top of the list. Our emotions influence our relationships, our work, our lifestyle, our sense of self, and our decisions, big and small.

Darwin was fascinated by emotions, and concluded that emotions were there, in essence, to warn us very quickly whether a situation is safe. In this respect and many others, we recognise the importance of our emotions. We know that fear helps us cross the road safely, that anger can give us strength, that love keeps us bonded to others.

But often we have a complicated relationship with our emotions, branding some as good and others as bad. We might suppress and ignore the ones we don't want or that we don't deem 'appropriate', and chase the ones we do, potentially to our detriment. So here's a brief overview of the neuroscience of emotions and the different areas of the brain that are involved in human emotion, as well as an explanation into the difference between emotions, feelings, and moods.

The first thing to know is that our brain can roughly be divided into three areas: lizard brain, mammal brain, and human brain.

Lizard brain is a deep structure and it's priority is to keep you alive. Lizard brain involves itself with breathing, digestion, keeping your heart beating. Lizard brain doesn't really care what you think or feel I'm afraid.
Wrapped around lizard brain is mammal brain, otherwise known as the Limbic system. Your Limbic system is concerned with safety. This is the area of the brain where you keep track of past pain and pleasure memories. All mammal brain wants to do is keep you safe, so if you have survived up until now by doing certain things, mammal brain will push you to keep repeating those same behaviours. Mammal brain absolutely hates change.
Human brain, or the neocortex (at the front of the brain), is the area of the brain we can most consciously access. It is the home of rational thought, learning, decision making, empathy and creativity.

Importantly, these different areas of the brain do not always agree with one another. If human brain wants to try out a new hobby, mammal brain might try and put human brain in its place, inducing anxiety and fear in order to dissuade human brain from taking such a bold leap into the unknown.

Our brain is covered in neural networks that get stronger or weaker depending on how often they are used. The ones that get used repeatedly become very strong 'neural highways': these define our default thoughts, emotional profile, and personality. The good news is that our neural pathways can be changed; this is called neuroplasticity.

So, what are the major emotions at the root of our neural networks? The spectrum of human emotion contains eight major emotions: sadness, shame, disgust, anger, fear, startle/surprise, excitement/joy, and love/trust. As you might have immediately noticed, all of us are a little unbalanced, with more major emotions available to us on the side of the scale that mostly characterises 'escape' rather than 'attachment'. Unfortunately, evolutionarily speaking it was more important for us to stay safe than have a good time.

Sadness tries to tell us that something in our situation is not right
Shame is our moral compass of sorts, but a very complicated emotion that can become deeply harmful if disproportionately attributed to particular situations. Our reaction to shame can either cause us to withdraw from engaging in the activity that resulted in this emotion, or drive us to work harder in order to avoid the feeling the next time around
Disgust serves the evolutionary purpose of keeping us safe from microbial harm. Disgust stops us from eating gone-off food, and keeps us at a distance from other things that we deem to be dangerous to us in terms of our health
Anger tries to change the situation. It is not passive like sadness. Anger is extremely situational in terms of how useful it is
Fear is experienced when we perceive that, firstly, there is a potential danger and, secondly, that we are relatively powerless over this danger. Fear inspires the fight or flight response
Surprise falls on both sides: we all know there are good surprises and bad surprises. When we feel surprise, we don't know what the outcome is, so our brain and body recruits extra energy in order to prepare for what might come to pass. This happens in the form of endorphins flooding the brain, helping us to feel relaxed
Excitement/joy are centred around pleasure and reward
Love/trust rely on predictability. These emotions are built up, as we build up a back-catalogue of positive, reinforcing experiences and memories around another person. These emotions also take into account how people like this new person have treated you in the past.

What are the areas of the brain involved in emotional response?

There are a few key areas that make up how emotions work in the brain. Our prefrontal cortex, which exists in human brain, is involved with emotional regulation and decision-making. This is where we store our sense of self, our value system, our self-control. We use the prefrontal cortex to suppress emotions.

The next key area is the amygdala. Our amygdala assesses our environment for potential danger and conjures the anxiety, fear, and anger that we might need in order to respond to this potential danger. The amygdala is also where we store emotional memory.

Our thalamus receives information from the senses - sight, touch, smell, hearing, taste - and sends information to relevant areas of the brain.

Our hippocampus is where we store memory. We also use it for navigation. The hippocampus stores the physical sensations of emotion.

How do these areas work together in an anxiety response?

Whilst our amygdala has been very helpful to our survival throughout evolution, individuals with anxiety disorders might be living with an over-active amygdala that perceives danger and threat disproportionately, and floods the brain and body with the same emotions that we might have needed in order to avoid real predatory dangers in the past.

When we perceive something that makes us feel fear or anxiety, our thalamus sends this information to our amygdala. The amygdala checks in with our hippocampus, to see whether we have previous memories that might inform us as to how to behave in the situation now. If our hippocampus shoots back painful emotional memories, we respond with fear and anxiety. Strong emotions can cause our rational brain to shut down. Our amygdala is much quicker to respond than our rational brain. Anxiety and fear leads to shallow breathing: this starves the brain of oxygen and leads to the areas of the brain not involved with survival to take a back seat. Rational thinking, creativity, and empathy are all shut off to us.

Breathing exercises can therefore be very helpful when experiencing fear or anxiety; ensuring that your brain is receiving the oxygen it requires in order to function properly will support you in better managing your emotions.

Emotions, feelings, and moods

Largely, we experience emotions in response to a specific external stimulus, but that isn't always the case. Our thoughts can also trigger emotional responses. If our human brain conjures up a thought, or a memory, of a time we felt shame or anger for example, mammal brain can be triggered into producing a physical emotional reaction. These are feelings. Feelings are different from emotions therefore in that they can be rationalised. An emotion happens very quickly; feelings are responses to the environment combined with our thoughts, interpretations, or inner beliefs about the situation. For this reason, our feelings are more manageable than our emotions: we can question our feelings, reflect our thoughts back to ourselves and question their validity.

Emotions and moods are also distinct. Whereas emotions are rapid-onset, specific responses to specific events that give us information about our current situation, moods are much harder to define. Moods often have a more gradual onset, and it isn't so clear what they are caused by. Moods give us information about our current state of self, our inner system. Unlike emotions, moods are therefore unhelpful when it comes to decision-making. Emotions, as they inform us about our current situation, are vital to the decision-making process. We are often instructed that there is a difference between 'following your head' and 'following your heart', the latter sometimes looked upon as synonymous with being foolish or at least irrational, but suppressing your emotions when decision-making can lead to ongoing indecision. Refusing to listen to what your emotions are telling you can leave you in a stressful state of 'analysis and paralysis', unable to move forward.

We may sometimes think life would be easier if our emotions were more predictable, more peaceful, or simply less pervasive, but they are one of our most important resources and are ultimately here to serve us.