Updated: Jan 24
In 1953, two researchers from McGill University discovered that when they electrically stimulated specific regions of a rat's hypothalamus, they could activate the brain's reward system.
Convincing experimental results
The experiment was designed such that, when a rat pressed a lever, it was 'rewarded' through an electrode attached to the rat's brain. The rats clearly liked this, so they kept pressing the lever.
It was a revolutionary breakthrough that allowed scientists to model pleasure, reward and its effects on behaviour in their test subjects. According to the study, "rats perform lever-pressing at rates of several thousand responses per hour for days in exchange for direct electrical stimulation of the lateral hypothalamus." The experiment further showed that"rats will forgo food to the point of starvation in exchange for brain stimulation."
But what drove the rats to do something that was clearly so detrimental to them? What drove them to rather starve to death than pull the lever? The answer is dopamine. And the results are not just limited to rats— this phenomenon has been replicated in every vertebrate tested, including humans.
Dopamine as an addictive reward
Dopamine is the chemical that plays a salient role in regulating motivation and reward-driven behaviour. Whenever we do something enjoyable- whether that be eating food or interacting with friends— our brain rewards us by releasing dopamine. It therefore encourages certain behaviours, dictating the system of pleasure, and its counterpart, pain.
Yet it is due to the abundance, ease of availability and intensity of dopamine which we are exposed to today that frames the modern struggle.
Early humans had to track, hunt and kill their food, and dopamine was essential for driving this difficult and often painstaking pursuit. Today, we have Deliveroo. We are often being rewarded when we shouldn’t be- like scrolling through Instagram for 2 hours straight (which the brain rewards as social interaction), almost becoming like the rats in the experiment!
Dopamine exposure also leads to tolerance- and just like with any other drug, we eventually need more of a substance or increased levels of activity to feel the effects we initially did. The problem here is that we are then driven towards artificial activities which elicit even higher doses of dopamine, whereas meaningful returns in life are often found way lower on the dopamine scale - think completing an essay, reading a book, starting a business or eating healthy.
To accomplish great things means we need to learn to fall in love with boredom. It requires deep reflexive work. It is the only way we can write a 400-page book or build a billion-dollar business from scratch. Yet, the instant gratification that social media, Netflix and Deliveroo brings is the antithesis of this. I am at my most productive after a (mild) dopamine fast, and the concept of overstimulation and dopamine tolerance is one that I keep in mind throughout my daily life. The more we can cut down on artificially inflated dopamine hits, the easier our brain can encourage us to do the hard things that yield the greatest returns in the long-run.