Inside your head, nestled deep behind your brain’s neocortex is a relatively ancient part of the brain known as the basal ganglia. This little blob of tissue receives inputs from many different cortical regions, including your frontal cortex (thinking, working memory) and motor cortex (physical actions).
The problem the basal ganglia solves is that our brains are massively parallel computing structures. Billions of neurons and trillions of synapses all firing independently. Yet, we need to take one and only one action at a time. Try to sit down while jogging and you’ll probably fall.
How the basal ganglia accomplishes this is with a pattern called the motor loop. Basically, it locks all actions by default. Only when an action gets enough support from dopamine-carrying neurons from the substantia nigra, does it go through. These dopaminergic neurons are trained to be reward-predictors — anticipating which set of actions will lead to the best rewards.
The circuitry guiding our thoughts and actions is exquisitely complicated. I’ve only provided a crude summary. But it does have a big limitation — our motivational impulses are remarkably short-term. As motivational researcher Piers Steel commented in our interview:
A week is actually, motivationally a long, long way off. A couple days, yeah, that’s pretty much it.
Motivation comes with an eye-dropper when you want it, and a firehose at the end. What we want is a nice tall glass of motivation, but we don’t really have that. We have this really messed up system.
In brief, while we have an excellent system for predicting rewards and choosing the best action to take, the system is remarkably short-sighted. Messed up indeed.
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