Dopamine - Your Happiness is Now
What is dopamine? Where does it come from? How does the brain use it?
Hey Brain Rewirers,
Welcome to this week’s newsletter! Let’s chat about dopamine.
Dopamine: What is it and where does it come from?
First off, what is dopamine? It is a chemical that acts as a neurotransmitter and neurohormone. It is made inside neurons, starting as tyrosine which enters neurons via the bloodstream and can be taken in through our diet1. Neurons turn tyrosine into L-DOPA, and then finally into dopamine1. Dopamine is then released at the synapse. Dopamine signalling is stopped by reuptake into the presynaptic neuron or by uptake into astrocytes (other brain cells present at synapses) that can breakdown the dopamine1. Â
Great…so which neurons make it? Well, there are two areas in the brain with dopamine-containing neurons: the zona compacta of the substantia nigra (SNc) and the ventral tegmental area (VTA)2. These dopaminergic neurons have long axons and project to overlapping and adjacent regions. The SNc primarily projects to the striatum2. This is known as the nigrostriatal system and is strongly involved in motor function. The VTA projects mainly to the nucleus accumbens, but also the amygdala and hippocampus2. This is known as the mesolimbic dopamine system. Projections from the VTA to the medial prefrontal, cingulate and perirhinal cortex are known as the mesocortical system2.
What I hope you can appreciate from the above paragraph and figure is that dopamine is not localized to one specific area or important to only one brain function; it is widespread and involved in many brain processes. Dopamine is involved in movement, reward, reward prediction, motivation, pleasure, and memory2,3.
Dopamine – Your Happiness is Now
Dopamine is classically known as the reward neurotransmitter, but it is actually more prevalent in the pursuit of the reward, i.e. motivation.
Let’s take a little look at how dopaminergic neurons respond when there’s a reward4.
When there’s an unpredicted reward, dopamine neurons fire more frequently.
When there is a predicted reward, dopamine neurons don’t fire any extra at the reward, but fire extra at the stimulus associated with the reward.
When there’s a predicted reward that isn’t received, dopamine neurons stop firing.
This makes sense; when you’re first establishing a habit, for example, going to a café, your brain doesn’t necessarily predict a reward of coffee and cake because it hasn’t been to that café before. So, you get that coffee and cake, and it’s an unpredicted reward. Dopamine surge! But, when you go back to the café, driving the same route might cause that dopamine surge, and seeing the café sign might cause the dopamine surge. But, getting the coffee and cake that you expected won’t give you that big dopamine hit. However, let’s say they’re all out of your favourite cake. You don’t get your expected reward, so you will see a reduction in dopamine firing!
Thus, in the beginning of learning an association, the reward itself will cause extra dopamine release. But, as your brain learns the place, smell, feel, etc. associated with the reward, extra dopamine is released not at the reward but in anticipation of it. There are a few ways this can relate to everyday lives:
Forming habits, good or bad: Environmental cues for rewards are important in motivating us to do things. If you’re trying to maintain a habit, use this to your advantage and keep those environmental cues close to you. I know that if I can get running gear on, I’ll usually end up going for a run. If you want to break a habit, remove those environmental cues. If I walk down the street with the bakery, I am almost guaranteed to ‘just stop in and have a look’. Â
Our happiness: Achieving goals, i.e. a reward, will give us a dopamine hit. But that hit doesn’t last forever. Happiness isn’t something that will come ‘when you get that promotion’ or ‘when you buy that new car’. We have a baseline level of happiness that can temporarily increase through one-off events, like getting a promotion. To permanently increase baseline levels of happiness we need to form good habits:
Practising Gratitude
Engaging in Random Acts of Kindness
More tips can be found in my book, Rewire!
If you want to know more about dopamine, how to form habits, and improve your happiness, you can find it all in my book!
Until Next Week,
Nicole x
P.S. Leave a comment with topic requests for future weeks!
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