Dopamine, explained

Dopamine, a chemical messenger in the brain, used to be neuroscience jargon — something you’d read about in a biology textbook. But today, dopamine has become a cultural catch-all, shorthand for focus, yearning, and joy.

Scroll through TikTok or sit next to a Silicon Valley software engineer at a dinner party, and you’ll be bombarded with dopamine-related life hacks. Struggling to stay off your phone? Maybe you’re due for a dopamine detox. Concerned that you’re not enjoying life like you used to? Try dopamine fasting or, for a quick pick-me-up, get dopamine dressed.

Wanting to hack your brain isn’t some niche thing. Celebrity neuroscientist and podcaster Andrew Huberman’s 2021 “Dopamine Masterclass” episode, “Controlling Your Dopamine For Motivation, Focus & Satisfaction,” has racked up over 9 million views on YouTube — a staggering number for a 136-minute neuroscience explainer. This video and others like it offer techniques for controlling dopamine release. Some are behavioral, like quitting sugar or abstaining from pornography. Others involve buying supplements, phone apps, or life coaching.

But in reality, dopamine does both more and less than pop culture gives it credit for. While dopamine-driven wellness trends often hinge on its role as “the pleasure molecule,” most neuroscientists today agree that dopamine doesn’t represent pleasure at all — at least not directly. Its role in the brain is wide-reaching and nuanced, shaping everything from motivation to nausea. Outside of the brain, it helps to widen blood vessels, lower white blood cell activity, and more. Even plants make dopamine! 

At the same time, dopamine doesn’t singularly drive our productivity, our mood… or anything, really. Silicon Valley optimization evangelists say that if we can hack our dopamine systems, we can maximize productivity. This both oversimplifies the vast complexity of human brain chemistry, and overstates our capacity to optimize consciousness.

“People like Andrew Huberman are taking the incredible things we’ve learned and using them for marketing,” said Nandakumar Narayanan, assistant professor of neurology at the University of Iowa.

There are nuggets of truth buried in the deluge of dopamine-obsessed trends, but its precise function is still a hot area of active research. Dopamine’s evolution from humble neurotransmitter to cultural icon says more about our collective desire to regain control of our impulses than it does about the chemical itself. Here’s what we actually know — and don’t know — about dopamine, and how to separate helpful advice from pseudoscientific hype.

Discovering dopamine

“Dopamine is probably the most famous neurotransmitter in the brain,” said Kent Berridge, a neuroscientist at the University of Michigan. “It has a long history, and a lot of baggage.” 

Until about 70 years ago, dopamine was just 3,4-dihydroxyphenethylamine, a chemical found in the body that early 20th-century scientists guessed had something to do with heart rate and blood pressure. In 1952, the chemical got its snappier name: dopamine.

In the early 1900s, most scientists thought dopamine was no more than a half-formed version of norepinephrine, a hormone involved in the fight-or-flight response. But in the late 1950s, German-British biochemist Hermann “Hugh” Blaschko noticed that dopamine was stored in the brain, and therefore must be more than an ephemeral midpoint in the creation of another chemical. Swedish pharmacologist Arvid Carlsson ran experiments that confirmed dopamine was a neurotransmitter in the brain — but neither he, nor anyone else, knew what it really did there.

Parallel research into Parkinson’s disease led to a breakthrough: Neurologists realized the disease’s characteristic tremors and muscle stiffness were tied to the loss of dopamine-producing cells in a part of the midbrain that controls movement. Levodopa (L-DOPA), a dopamine precursor, was introduced in the 1960s as a “miracle drug” for Parkinson’s, bringing once-immobile patients back to life temporarily. (Robert De Niro and Robin Williams star in a movie about it, an adaptation of Oliver Sacks’s 1973 book Awakenings.)

Dopamine’s first moment in the spotlight inspired more pharmaceutical research. Haloperidol, an antipsychotic commonly used to treat schizophrenia, first went through clinical trials in 1958 — it effectively treated psychosis, but scientists didn’t know why. But in the 1970s, the discovery of dopamine receptors in the brain led to an important realization: haloperidol binds to and blocks a certain type of dopamine receptor, suggesting that dopamine — specifically, having too much of it — plays a central role in schizophrenia. 

Links between dopamine and mental illness kept popping up in clinical research: Addiction, ADHD, and depression all seemed related to changes in the dopamine system. ADHD medications like Adderall and Ritalin, as well as addictive drugs like cocaine and methamphetamine, target the dopamine system, implicating it in habit formation, craving, and euphoria. Together, these results caused a paradigm shift in our understanding of dopamine: If the chemical is involved in disorders of attention and thought, and in substances that affect how we think and feel, then it must play a role in cognition.

If our relationship with dopamine goes both ways, meaning our behaviors affect dopamine signaling and dopamine shapes how we feel, that opens the door to optimization. If dopamine responds to what we do when we’re not thinking about it, maybe, just maybe, we can fine-tune our dopamine systems through intentional lifestyle changes. 

How does dopamine work? 

Despite its A-list status, dopamine is just one of the brain’s many chemical messengers. 

Only a tiny fraction of neurons make dopamine: roughly 400,000 out of 86 billion, or 0.000005 percent. Dopamine-producing neurons are mostly clustered in the midbrain, where they play a key role in motivation, learning, and decision-making. These functions fall under the wide umbrella of action selection: weighing options, deciding what’s best and whether it’s worth doing, and sending commands to the rest of the brain. 

“They’re like the influencers of your brain,” said Narayanan.

Countless TikTok videos will obsess over “dopamine levels.” According to social media, dopamine levels spike when you indulge in everything from sex to exercise to creative expression; they fall when you’re sad or unmotivated. 

That’s the simplified social media explanation. But Talia Lerner, a neuroscientist at Northwestern University, told me, “it’s a little bit more nuanced than just one thing that moves up and down.”

Dopamine neurons receive inputs from a large swath of the brain: your sensory, motor, and limbic systems all send information to the midbrain. “Some of these inputs are designed to calibrate how much dopamine you get, based on your needs,” Lerner said. And because dopamine neurons send signals to different places at different times, she emphasized that “there’s not just one dopamine signal.”

There are two main kinds of dopamine signaling; dopamine is released when a neuron fires in response to some specific stimuli. But these neurons are also firing steadily in the background all the time, maintaining a baseline level of dopamine that fluctuates throughout the day. Kurt Fraser, a neuroscientist at the University of California Berkeley, told me that the amount of dopamine floating around in the brain is constantly fluctuating, but “you wouldn’t have any conscious awareness of being in a ‘high’ or ‘low’ dopamine state.”

To understand what dopamine is actually doing after it’s released, it’s helpful to know what it’s not doing. 

All of the neuroscientists I spoke with made one thing clear: dopamine is not a “pleasure” chemical. Despite the pervasive belief that dopamine is the thing that makes us feel good, “that hypothesis was debunked in the ’80s,” said Arif Hamid, an assistant professor of neuroscience at the University of Minnesota.

“If we have to put a label on dopamine,” Fraser said, “I would say it’s like your desire chemical.” But not abstract goal-oriented desires, like desiring a promotion at work. It’s a more urgent, almost animalistic desire, or want: what you feel when you’re compelled to snack, check Instagram notifications, or smoke a cigarette.

Its exact function is confusing even to many neuroscientists. For a long time, they did think dopamine represented pleasure — after all, it’s released when pleasurable things happen. “If you step outside and the world beckons, and people are attractive and interesting to interact with, your mesolimbic dopamine system is clearly responding.” Berridge told me. “It makes the world inviting, and it makes the world attention-grabbing.” 

Berridge ran a series of pivotal experiments about 30 years ago in which his research group prevented lab rats from producing dopamine and observed the consequences. Without it, the rats couldn’t even move to feed themselves. But when hand-fed something yummy, the rats still liked it. Similar behaviors have since been reproduced in human experiments. So, even with zero dopamine, one can still enjoy pleasurable things; neuroscientists suspect that pleasurable feelings themselves are actually mediated, at least in part, by naturally produced brain chemicals called endogenous opioids that bind to the same receptors as synthetic opioids like oxycodone.

What dopamine does is make you want things. It is now understood as playing an important role in motivation, cheering the brain on as it makes decisions and sends commands to the body. Beyond this, Hamid added, “it’s also this really awesome coach,” teaching us how to make better decisions in the future.

Around the same time Berridge and colleagues were studying dopamine-less rats, German neuroscientist Wolfram Schultz’s team was recording the activity of dopamine cells while monkeys reached for treats, hoping to better understand Parkinson’s disease. Instead, they noticed something that revolutionized our understanding of dopamine: rather than firing in response to the treat itself, the dopamine neurons responded to the sound of the treat box opening. Then, once the monkeys got familiar with the task, their dopamine neurons stopped firing altogether.

In other words, dopamine was responding to the treat being a pleasant surprise — not the reward itself. This signal, called a reward prediction error, tells the brain how far off its expectations were from reality, and it is crucial for trial-and-error learning. 

Dopamine is involved in both motivation and learning, but the two processes don’t exist in isolation. Motivation focuses your learning efforts, and you can learn to be motivated to do something. Stephanie Borgland, a neuroscientist at the Hotchkiss Brain Institute at the University of Calgary, told me, for instance, that dopamine neurons send signals to the prefrontal cortex that appear to help you figure out what you should pay attention to. Dopamine also drives the formation of habits, behaviors we’ve learned to be motivated to do, like checking Instagram for fresh notifications when we’re craving social validation. 

The problem, Borgland said, is that “your brain doesn’t know whether it’s developing a new skill, or whether it’s about to be a bad habit.” 

Once a habit forms, it’s out of the dopamine system’s hands — and this can create a rift between what makes us happy, and what we want. This is why someone with substance abuse disorder can feel compelled to use drugs without deriving pleasure from it. New drugs like Ozempic, which act on neurons that receive dopamine signals, might even be able to close that gap, bringing cravings down to a more manageable intensity.

The deep connection between addiction and dopamine makes the chemical an easy target for self-help guides, something to “optimize” to facilitate healthier relationships with drugs, work, and technology. But Borgland thinks it’s mostly “a lot of bullshit.” And she’s not alone.

Dopamine detoxing, hacking, and fasting: is any of it real?

As academic dopamine research flourished, the chemical started popping up in movies, music, and tattoo trends. In 2014, I had a friend stick-and-poke a dopamine molecule tattoo on my ribcage. But today, dopamine is presented by celebrity scientists like Huberman and Anna Lembke, author of the bestselling book Dopamine Nation, as both the root cause and the solution du jour of most mental maladies — often as a strange blend of cognitive behavioral therapy, engineering optimization, and “wellness” a la Goop.

That said, not one neuroscientist I spoke to (nor, for what it’s worth, any neuroscientist I interacted with during my time in academia) felt good about the portrayal of dopamine in the media. When asked about wellness advice doled out by Huberman and other optimization-minded influencers, Narayanan said they are “doing science and the general public a disservice by oversimplifying a complex topic.” 

The problem with trends like dopamine fasting — which instructs people to take intentional breaks from stimulating, potentially addictive things that might trigger dopamine release, in an effort to reset the mind — is that it puts too much stress on dopamine. One chemical doesn’t have the power to single-handedly overhaul your mental health.

In many cases, the emphasis on dopamine appears to be more semantic than biological. When people attach “dopamine” to almost anything, they are often simply discussing habits, addiction, and control, and throw in neuroscience jargon for extra heft. Dopamine fasting, for instance, is essentially cognitive behavioral therapy, with “dopamine” as a metaphor for impulsive pleasure-seeking. Cameron Sepah, who published a now-viral guide to dopamine fasting in 2019, even told the New York Times that the “dopamine” of it all isn’t meant to be taken literally — but it “makes for a catchy title.”

But there’s a reason why today so many of us turn to dopamine-labeled techniques to free ourselves from our impulses — especially those relating to screen time. In the late 2010s, startups like (now defunct) Dopamine Labs brazenly invoked dopamine to sell neuromarketing strategies that helped tech companies exploit the brain’s reward system to get consumers hooked on their platforms.

Neuroscientists agree our phone apps are habit-forming by design, and “it probably does activate your dopamine system,” said Lerner. Apps like Instagram and Hinge deliver notifications and hot matches on a variable reward schedule, like a slot machine. If your brain can’t figure out how to predict when a reward will come, every ping will feel like a surprise: a positive reward prediction error signaled via dopamine. It’s not necessarily that the apps are making your overall dopamine levels high or low, Lerner clarified, but they are made to reinforce your scrolling behavior. 

But then saying that these dopamine hits accumulate and ultimately make us unable to experience pleasure, Fraser said, is a stretch. Fads like dopamine fasting are built upon the idea that overindulging in compulsive, hedonistic behaviors will cause you to “burn out” on dopamine, but this doesn’t quite align with the timescale of human dopamine release. 

Trends like dopamine dressing by wearing bright, fun clothing as a mood booster also rely too heavily on dopamine to explain something with many underlying causes. A little Hot Girl Walk in clothes that spark joy can be a great pick-me-up, but Borgland suspects that “wearing your favorite shirt or whatever is probably modulating a whole bunch of different neurotransmitters and neuropeptides,” including serotonin (which is produced and released through entirely different processes from dopamine). “It’s not just a single neurotransmitter.”

Narayanan gave this example: if you buy a cupcake, eat it, and it’s delicious, dopamine is certainly part of that experience. “But reducing that cupcake experience to a dopamine pill is not going to work.” He laughed. “In fact, it would make you throw up.” (Nausea is a common side effect of medications that mimic dopamine.)

Your brain is more than a gas tank filled with dopamine. You can’t simply top it up to increase your mood or your working memory, or your ability to focus. The relationships between mental health, productivity, and dopamine signals are very complex, and we are just beginning to understand how brain chemicals shape how we feel, but Lerner is confident that, “at the very least, we can say that it’s not whether your dopamine is ‘too high’ or ‘too low,’ because that’s meaningless.”

While neuroscientists know more about dopamine than they do about many other neurotransmitters, many questions are still unanswered. Last year’s Society for Neuroscience meeting, a conference bringing together thousands of brain scientists, featured dozens of dopamine-related presentations. 

“We’re just entering a phase now where we’re starting to realize that dopamine is involved in a lot of processes that we didn’t fully appreciate,” Hamid said.

Why does the idea of a “pleasure chemical” resonate with us?

We’ve known for decades that dopamine isn’t strictly a “pleasure chemical,” but pop culture still portrays it as one. Even Franc Moody’s 2018 dance banger “Dopamine,” which opens with a scientifically accurate description of dopamine synthesis, uses dopamine as a metaphor for being a hedonistic hottie on the dance floor. Berridge said our outdated understanding of dopamine is so deeply ingrained that many neuroscientists still slip up. “They’ll write phrases that only make sense if dopamine were pleasure,” he said, then laughed. “I think it’s their former self taking over again.” 

Maybe the idea resonates for the same reasons as other formerly clinical concepts like dysregulation do: It provides a clear (arguably too clear) framework for understanding ourselves.

If we imagine dopamine as a lever we can pull to boost our focus, or a rising and falling tide that explains why we feel energized or disengaged, we regain a sense of power over our minds. The reality of dopamine’s more nuanced and mysterious function inside our brains is much less satisfying. 

Fraser suggested that people may be invoking dopamine “because there’s enough known about dopamine that we can talk about it as if it might impact our lives.” But he worries that “dopamine is just a straw man” empowering people to claim that they know how we can control our brains. The temptation to buy into that notion is powerful. As we continue to collectively fight a losing battle against the attention economy, we want agency and to know that our problems aren’t our fault. 

We’re in an era of constant distraction. We all have smartphones, and some fear that they’re ruining our brains. As the amount of time we spend on TikTok grows, news articles are shrinking, and songs are getting shorter. 

While the quantity and ease with which we can access distracting content is new, distraction-seeking isn’t unique to our dopamine-conscious era. For centuries, humanity has searched for escape from the ordinariness and angst of our lives. As early as the mid-17th century, French philosopher Blaise Pascal wrote that distraction-seeking is completely natural, even for the wealthiest of people: “The king is surrounded by persons who think only how to entertain the king, and to prevent his thinking of self. For he is unhappy, king though he be, if he think of self.” 

And as long as we’ve been seeking distractions, we’ve also been trying to free ourselves from them. For thousands of years, meditation has been embedded in many spiritual belief systems as a means of finding clarity and enlightenment. 

Optimization-oriented content creator Richard Yong, known to his 3.57 million YouTube followers as Improvement Pill, told the San Francisco Chronicle that “dopamine fasting is basically just an easy mode version of a Vipassanā retreat,” a specialized, intense kind of meditation practice. Taken to a lesser extreme, intentionally abstaining from things like checking your phone for a couple hours before bed feels like common sense (and good advice!). It only gets weird when you try to draw a direct line between these behavioral changes and a single neurotransmitter. 

Dopamine has become a byproduct of all that it tries to explain: impulse, addiction, our drive toward optimization. As technology and society writer L.M. Sacasas wrote, “It is a powerful and catchy meme, although one that is offered in the best spirit. For these reasons, I fear that it may trap us in the very patterns that it seeks to overcome.”

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