phasic dopamine

Phasic dopamine is a brief exaggerated spike which encodes reward prediction error in the brain - the difference between what we expect and what we get.

This is when we find a berry on a tree or a tiger in the bushes and learn 'good' or 'bad'. Over time these learnings can become convoluted and contradictory; we start finding tigers in the trees.

Phasic dopamine, in its extreme form, is what encodes trauma and addiction. Every form of deep learning can be seen on a greyscale between equanimity and trauma.

Phasic dopamine is involved in both positive and negative learning. It is like a magnet with two poles; all we control is the strength of the magnet. 

Phasic-stimulating activities are flashy lights, high risk, thrill seeking gamification. They are social media, doomscrolling, drug taking and high-intensity training. These activities want to be avoided when possible and limited to midday when not; your dopaminergic environment is most resilient between late morning and early afternoon.

Every phasic spike results in a commensurate crash which we instinctively try to counteract with another phasic spike. This is the natural reinforcement learning cycle, but we also need to learn to unlearn, or the mind becomes noisy, scattered, and trapped in loops, as is common with PTSD and ADHD

Phasic dopamine primarily interacts with D1-type receptors in the brain and tonic dopamine sustains background activity through D2-type receptors. The way we can decrease the impact of D1-activation is by increasing D2 activity through modulating dopaminergic tone. This is also how we start to unlearn the maladaptive lessons of life.

In the car analogy, phasic dopamine is your nitrous boost; useful for rapid acceleration, but it will destroy the engine if it’s the only system you rely on.