Dopamine

Dopamine

  • Reading time:11 mins read

What is it and why you should care

In short:

Dopamine motivates us to act. In excess it makes us addicted. Modern activities hack our biology to secrete excessive dopamine.


[natural: reward-motivation neural pathway] 

Explaining addictions starts with neurology. The key to addictive behaviour is the mesolimbic/ mesocortical dopamine system. Its central component is the neurotransmitter dopamine.

Dopamine is they key to addiction. You feel pleasure after eating candy or getting a like on Instagram. That is dopamine binding to its receptors. Dopamine is often called the pleasure molecule. But it’s more accurate to say it is the motivation molecule. It is the basis of the human intrinsic reward system. It is what drives us to action.

“Dopamine is not about the happiness of reward. It’s about the happiness of pursuit of reward that has a decent chance of occurring.” Robert Sapolsky

Let’s examine the dopamine cycle. First time you do something pleasant, you get a dopamine hit. This feels good. Let’s say it’s the first time you eat cotton candy. As you eat it, the high energy content of sugar activates signals in your brain telling you that it is good. Dopamine surges. It binds to its receptors. You feel pleasure.

What happens next time you eat cotton candy? The same thing. But now you get a small dopamine hit before you eat it, in anticipation of the pleasure. This is the crux of human motivation.

As you repeat eating cotton candy more times, the quantities of dopamine change. The anticipatory dopamine hit increases, while the reward hit decreases. You feel higher motivation to do the behaviour, even as its reward diminishes.

What can release dopamine? Anything that is pleasant for you. Example activities that release dopamine:

eat a doughnut,

eat a steak,

eat anything,

new messages in chat,

an email,

turn up the heat when you are warm,

read an article,

scratch an itch,

indulge in an addiction,

look at a pleasant view,

someone caressing you,

lick salt,

watch a video,

sit down when tired,

discover new information,

open Facebook,

someone smiles at you

Most of our behaviour has a dopamine component. Otherwise we would not do it. This is why it is the motivation molecule.

Addictive behaviour are not special because they release dopamine. But rather because of the quantity and flow of dopamine. They elicit unnaturally high dopamine spikes. And they morph into a pattern of very high motivation dopamine hit, but low reward hit. Many of them, change your tolerance of dopamine. Your system get overwhelmed with the excessive high so often, its sensitivity decreases. Some addictions even damage your dopamine system permanently.

Addicts are dopamine-resistant.

Take smoking. First time you smoke is for reasons unrelated to cigarettes as a product. Most people do it to be cool in high-school. But when you do, the nicotine releases dopamine and you feel good. You might also feel sick from that first cigarette, but it does not matter. Next time the opportunity of smoking appears, your brain releases a tiny dopamine hit. This pushes you to smoke again. If you do, you then get the reward.

Next time you have the opportunity to smoke, the anticipatory dopamine hit will be higher. You feel a stronger urge to smoke. Next time even stronger. And so on.

The dopamine pathway is self-reinforcing. The more you repeat a behaviour with an excessive dopamine spike, the stronger the urge to repeat it. The anticipatory dopamine increases.

Why does this happen? Dopamine used to signal pro-survival behaviour. Eating, resting, social validation. As you repeat a dopamine behaviour, your unconscious becomes more convinced that behaviour is advantageous to survival. Addictions hack the dopamine signal.

Dopamine is not an addiction mechanism. It is the crux of motivation. It is so important, that without it you lose the will to live. In an experiment researchers destroyed the dopamine behaviour in rats. These rats starved to death because they did not have the motivation to eat (or do anything else). 

For our ancestors dopamine rarely led to addictions. It is a signal that evolved to increase survival in nature. Addictions are not useful to survival. Humans changed the world, and created artificial dopamine-stimulating behaviours.

[modern: hack dopamine]

As any other part of the human body, the dopamine pathway is adaptable. Too much stimulation creates tolerance. Tolerance reduces the reward felt. In the short term this leads to more of the respective behaviour. In the long term it can compromise your ability to feel dopamine. Dopamine receptors die from overstimulation. You need higher and higher doses of dopamine because you have fewer receptors. 

What happens when you develop tolerance (or your receptors die)? You up the dose of addictive behaviour. The more you do it, the more you need to feel the same pleasure. There is a saying: ‘every smoker smokes as much as he can tolerate’. It means that every smoker wants to smoke as much as possible. The barrier is how sick he feels. The healthier he is, the more he can poison his body. But all smokers tend towards more. And the more they smoke, the more tolerance they build up, the more they have to smoke to get the same hit.

Then there is the dark side. When you are not doing the behaviour that over stimulates dopamine, you are in a dopamine deficit. You feel less dopamine than a non-addicted person. Dopamine deficit makes you lose motivation, have no energy and become depressed. This might be why there is a strong documented correlation between substance abuse and depression: 1, 2, 3. And there is a correlation between social media addiction and depression.

The incredible thing about dopamine it’s not specific to addictive substances. Almost any behaviour can trigger a dopamine hit. From classical addictions such as smoking, drinking, sugar, to modern recognized addictive behaviours like gambling, social media, sex, gaming, to almost anything, like collecting weird objects, sniffing used panties, intercourse with inanimate objects, schadenfreude — gloating over an envied person’s fall from grace [H. Takahasi et al., “When Your Gain Is My Pain and Your Pain Is My Gain: Neural Correlates of Envy and Schadenfreude,” Sci 323 (2009): 890; K. Fliessbach et al., “Social Comparison Affects Reward-Related Brain Activity in the Human Ventral Striatum,” Sci 318 (2007): 1305.], punishing norm violations (jerks) [D. De Quervain et al., “The Neural Basis of Altruistic Punishment,” Sci 305 (2004): 1254; B. Knutson, “Sweet Revenge?” Sci 305 (2004): 1246.], but also cooperation [A. Sanfey et al., “The Neural Basis of Economic Decision-Making in the Ultimatum Game,” Sci 300 (2003): 1755. Also see J. Moll et al., “Human Front-Mesolimbic Networks Guide Decisions About Charitable Donation,” PNAS 103 (2006): 15623; W. Harbaugh et al., “Neural Responses to Taxation and Voluntary Giving Reveal Motives for Charitable Donations,” Sci 316 (2007): 1622.], pleasant music. And many, many, more.

How can dopamine affect such a wide variety of completely different behaviours? If we only released dopamine for basic survival and reproduction activities (like hunting, sex, drinking, resting when tired, defecation, etc.) then we would still be apes in the bush. Homo Sapiens is more adaptable at an individual level than any other animal. This adaptability comes from our ability to reprogram our own motivation. The dopamine carrot drives our unconscious to initiative and adaptation.

What determines how much dopamine comes from an action? Its perceived value to survival and reproduction.

Our brain determines this value based on its model of the world. This model is obsolete, consisting of a Paleolithic worldview. It perceives many modern actions valuable for survival when they are not. Actions such as eating sweets, responding to notifications, scrolling social networks, and other addictions. These are pro-survival in a Paleolithic model, but in fact reduce survival or quality of life in the modern world.

The higher the perceived value of an action, the higher the dopamine incentive. You want to eat doughnuts more than celery. Doughnuts have a higher survival value than celery in a Paleolithic world of scarce food. Sex releases dopamine in all animals tested . [J. Cloutier et al., “Are Attractive People Rewarding? Sex Differences in the Neural Substrates of Facial Attractiveness,” J Cog Nsci 20 (2008): 941; K. Demos et al., “Dietary Restraint Violations Influence Reward Responses in Nucleus Accumbens and Amygdala,” J Cog Nsci 23 (2011): 1952.]. Food evokes dopamine in hungry subjects, but less so in satiated subjects .

The problem with dopamine is not its existence. The problem is when it is in excess. Addictions happen when the dopamine cycle is overloaded. You have higher than natural releases of dopamine. How does this happen? With stimuli that have not existed before in Homo Sapiens history.

Your dopamine system has evolved to life in the wild. Pleasures were subtle. Rest after a hard day of hunting and gathering. A small wild apple. A hug. Warmth of the fire at night. A soft and safe place to sleep. Sun after days of cold rain. Dance around the fire. Sex. Eating after several days of hunger.

How powerful is dopamine excess in creating addiction? To get a sense we can look at Parkinson disease. It is a neurodegenerative disease which involves a deficit of dopamine. Drugs meant to combat Parkinson increases sufferers’ dopamine. They turn almost 10% of the patients into gambling addicts. 

What can generate dopamine overstimulation? Unnaturally strong stimuli. Behaviours or substances that would have been unknown to our hunter gatherer ancestors. Or that would have been present in much lower quantities for our ancestors. Cocaine? check. Cigarettes? Check. Sugar? Check.

Every habit-forming drug: amphetamines, cocaine, nicotine, alcohol, sugar affects the dopamine system by dispersing much more dopamine than normal. This overload diminishes the neural pathways connecting the reward circuit to the prefrontal cortex, which is how we tame impulsive actions in favor of rational planned behaviour. It makes us more impulsive in pursuing cravings. The effect increases with usage: the more it happens, the more powerful it becomes.

Technology can create dopamine surges. A hundred likes for a selfie on Instagram when you regularly get 1 or 2 likes? Dopamine overload. A hot new match on Tinder? Dopamine overload. A notification on Facebook that turns out to be something pleasant, instead of random information? Dopamine overload.

Companies hack your dopamine system. Their success comes from getting as many people using the product as much as possible. The key goal of Facebook is getting more people to use their product more. The key goal of a drug dealer is getting more people to their product more. Chamath Palihapitiya, former Vice President of User Growth at Facebook said he felt ‘tremendous guilt’ at how they designed dopamine loops into the social platform 

The addictive power comes not from the size of the reward when doing the behaviour. It comes from the size of the dopamine surge in anticipation of the behaviour. Of course that a bigger behaviour reward will lead to a bigger anticipatory reward as well. As the behaviour repeats, the anticipatory reward increases. Thus a second factor is how many times you perform the respective behaviour. The more you do it, the more you want to do it. Any product or service that convinces you to use it daily stands a greater chance of becoming addictive. The incessant assault of notifications comes from companies that understand this fact. They are working to get you to use their product as often as possible.

Negative experiences with a behaviour should reduce the dopamine motivation for it. This should prevent us from repeating behaviours when we discover they pose a survival risk. Unfortunately this defense mechanism is ill suited for the modern world. The craving decreases only if we have extreme, life-threatening experiences with a product. Your addiction decreases only if you feel in immediate danger. That is why people give up an addictive behaviour after a close brush with death.

This protective mechanism does not come into action for most modern addictions. It cannot take into account long-term risks, or chronic health damage. Each cigarette is too small to trigger your fear. But all the cigarettes you smoke give you cancer.

In short:

Dopamine motivates us to act. In excess it makes us addicted. Modern activities hack our biology to secrete excessive dopamine.


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