Why We Buy Things We Don’t Need

Searching for an explanation for compulsive shopping, I recently ran across the story of a woman who couldn’t stop buying rabbits. Her husband told doctors that each day, she would visit the market and return home with yet another furry creature in a compulsive habit that appeared almost like an addiction. Then she would feel guilty about all the rabbits she had purchased.

The reason this 70-year-old woman was suddenly buying so many rabbits? She had been diagnosed with Parkinson’s disease, which scientists believe is caused by a lack of dopamine in some parts of the brain, and she had then been put on drugs to trick her brain into believing it was getting the dopamine it needed. But some patients who received these “dopaminergic” drugs started compulsively shopping, gambling, and binge eating—their brains were getting inundated with dopamine, which made rewarding behavior feel even better than usual.

I think about the woman who bought so many rabbits every time I look at the many recent Amazon orders on my account, or receive a new package on my doorstep and scurry to move it inside so my neighbors don’t judge my consumption habits. I know that buying more new stuff is bad for the planet—the production and use of household goods and services was found to drive 60% of greenhouse gas emissions—but every time I buy something, I get a little jolt of happiness that’s hard to give up. Like the woman buying rabbits, I can’t stop.

But a new book has helped me understand that my desire to keep buying things isn’t necessarily a personal flaw—it’s the way our brains have evolved. And there may be a way to break the cycle.

“All things being equal, we are predisposed to try to acquire more and more stuff, and to try and work less to get it,” says Ann-Christine Duhaime, a Harvard neurosurgeon who explored how to rewire the human brain to stop needing more stuff in her new book, Minding the Climate: How Neuroscience Can Help Solve Our Environmental Crisis.

We are, after all, evolved from blobs that survived because their networks of cells learned to repeat decisions like moving towards a tasty treat or backing away from a predator. Today, we have some 86 billion neurons, the “action cells” in the brain, that are constantly creating circuits to reinforce rewarding behavior, releasing dopamine as they do so, in order to help us learn how to get a reward. We seek out those releases in dopamine, and at the same time, learn to repeat the actions that lead to them.

Our brains especially like it—and release more dopamine—when we get an unexpected good reward, Duhaime says. Our ancestors likely learned the benefits of “intermittent small variable rewards,” as Duhaime calls them, to teach them to explore. Maybe they were walking through a new patch of woods and stumbled across an unexpected patch of blueberries, she writes. Different networks in their brains told them that the blueberries were a good thing, which also caused their brains to release dopamine, and they learned to repeat the behavior that led to the blueberries.

The good feeling associated with unexpected rewards is partly why we like shopping. Maybe you weren’t even thinking about buying watercolor paints and then you read something that reminded you that you like painting, and you went online to buy yourself some watercolor paints. Even better: the watercolor paints were less expensive than you expected and, when they arrived on your doorstep the next day, they were higher-quality than you thought they’d be. Your brain will be drawn to repeat the behavior that got you something unexpected and good.

You don’t buy those watercolor paints every day because the dopamine hit decreases every time you repeat the same new learned behavior. People get addicted to things when the appeal of getting that new, unexpected reward doesn’t fade with time, which helps explain why that woman who was on a drug that kept the dopamine flowing continued buying so many rabbits.

(Some scientists argue that modern society is so addicted to shopping because so many people are stuck in repetitive mind-numbing jobs—buying things is one of the few ways they are able to do something out of the ordinary.)

Read more: Here’s the Carbon Footprint of Four Families in a Week

Of course, all humans are different, and our brains work differently depending on our genetics and our life experiences. Maybe you inherited a particular kind of receptor for a specific neurotransmitter that makes you react faster in a certain circumstance, so you take more risks than most people do. Or you might have learned in childhood that overspending can lead to poverty, which made you thrifty even if your parents weren’t.

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A larger study of Parkinson’s patients published in 2010, for instance, found that not all people receiving dopamine treatments had a tendency to overshop. Those who had impulse control problems tended to be younger male smokers who lived in the U.S. and who had a family history of gambling, which suggested that both genetics and environment played a role.

That’s why Duhaime stresses that our brains are not “hard-wired” to keep consuming more and more. Yes, we have learned over time that the key to survival is acquiring more resources, but the brain also has a tremendous amount of plasticity. The challenge is that our systems are designed for short-term decision-making, and curtailing our own individual consumption for the long-term health of the planet may not benefit an individual person today. When a predator approached, we’d throw a rock at it and be rewarded, but the long-term deterioration of the planet is a little harder for the reward centers of our brains to understand, even if we are intellectually aware of it.

“The problem is, we topped out, and now more and more is bad for us,” Duhaime says. “It’s bad for us climate-wise, and it’s bad for us health-wise.”

The best way to alter the overconsumption habits that have gotten us here is not to stop buying things completely; a better solution may be to substitute new rewards for the old rewards that we know, in the long-term, aren’t good. I told Duhaime that as the days get shorter, I can’t stop eating chocolate just before bed for comfort, even though I know I don’t need the calories. She told me about her new before-bed treat: a glass of almond milk with a scoop of fancy cocoa powder, which gets her that same feeling of comfort without the calories of chocolate bars. Once she started losing weight, Duhaime says, the reward of being able to fit into her old clothes felt as good as the chocolate once did. We need that same substitution for shopping.

Buying used items, as I’ve written before, is an elegant substitution that could help fulfill our desire to acquire. You can buy something that’s new to you, and get that same good feeling of an unexpected reward without requiring a company to extract more resources from the earth.

Read more: I Tried Buying Only Used Holiday Gifts. It Changed How I Think About Shopping

Our current economy is still evolving toward a place where buying used items is rational; sometimes, buying new clothes online is cheaper and easier than buying old ones in a thrift store. But the secondhand market is growing—and is projected to more than triple within the next decade. And even companies like Apple, which long resisted calls from consumer groups to allow customers to repair their devices, rather than just buying a new one, now has a Self Service Repair Store that provides repair manuals and genuine Apple parts.

Creating social rewards can also help nudge more people toward behavioral change, Duhaime says. There’s a reason humans still cooperate and share—our brains get something out of having connections with other people. When like-minded people reinforce each other’s decisions—think about the successes of groups like Alcoholics Anonymous or Weight Watchers—they can help each other change. Already, there are so-called Buy Nothing groups cropping up, forming communities to help people exchange used goods—and there’s a hashtag #BuyNothingDay circulating on social media aimed at discouraging people from shopping unnecessarily on Black Friday.

Duhaime points to a successful project in the Netherlands called Eco-Team Programme, in which neighborhood teams got together to try and change their behavior, perhaps tracking the weight of the trash they generated or the amount of water they consumed. Over time, environmentally friendly habits replaced more harmful ones, as neighbors created new connections with each other by sharing the experience of changing their behavior. “If it’s not rewarding,” Duhaime says, “we simply won’t do it.”

Whether that approach would work in the U.S. is up for debate. There have been efforts to encourage similar behaviors. In his 1995 book, Ecoteam: A program empowering Americans to create earth-friendly lifestyles, David Gershon, an author and expert on social change, set out a strategy. It included forming teams of family members or neighbors and agreeing to some shared goals, like keeping their thermostats at 65°F or getting their names taken off junk mail lists.

Of course, the book is available on Amazon if you are hankering for something to buy.