Dopamine

Figure 1. Dopamine is not the goal. Dopamine release causes the progression to a goal.

Figure 2. Dopamine in action

Dopamine works as a type of proto-reward chemical. When your dog sees the ball you are about to throw it sets a dopamine dynamic where it releases the neurochemical dopamine which causes a craving for the ball. The dopamine is not the reward as the release of which only occurs in the wanting stage (Figure 2 - between the signal and work). When the dog actually gets the ball in the reward stage the dopamine disappears. and consciousness looks for its next trigger for a neural pathway to flow down (Figure 3). The main difference between you and your dog is that you can perform longer loops as opposed to shorter loops due to your neocortex having the ability to discern time. This is called the Curse of Sisyphus, dopamine far from being the reward molecule is actually the greed molecule.

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