How Credit Cards Affect Our Brains
Share Button

How Credit Cards Affect Our Brains

Buying with plastic doesn’t just eliminate a barrier to buying. It actively encourages purchases.

By Cheryl Winokur Munk
Tue, May 4, 2021 10:18amGrey Clock 2 min

It’s been known for decades that credit cards encourage spending. But why that happens still isn’t entirely clear. New research offers some fresh insight into the causes—and how consumers might be manipulated in an increasingly cashless society.

Research on credit-card spending has tended toward the explanation that delaying payment removes a barrier to purchases in shoppers’ minds. A study published in February in Scientific Reports found evidence of another kind of trigger. Differences it found in brain activity between shoppers planning to use a credit card and those planning to buy with cash indicate that buying on credit doesn’t just ease shoppers’ inhibitions, it actively encourages purchases, the researchers say.

The upshot: When people are shopping with credit cards and see a product they like, the neural network in the brain that produces a sensation of reward perks up, which seems to create a craving to spend, says Sachin Banker, assistant professor at the University of Utah, who worked on the study as a Ph.D. student at the MIT Sloan School of Management.

“You’re basically feeling more reward when you shop with credit cards,” he says. “We don’t see that with cash. It was actually a very stark difference.”

Researchers used a form of magnetic resonance imaging to measure the brain activity of the study subjects as they participated in a shopping exercise. Each participant was shown a total of 84 everyday products over the course of three sessions and was asked whether they would buy each product at the stated price. Half the products were offered for purchase by credit card and half for purchase with cash. None of the products cost more than $50.

The differences in the shoppers’ brain activity support the hypothesis that after repeated credit-card purchases over time the brain learns to anticipate the rewards of credit-card shopping, according to the report. And that suggests that consumers could be conditioned to spend through the use of various sensory rewards in new payment systems, Dr. Banker says. For instance, with digital payments the use of particular sounds or vibrations on your smartphone when you make certain purchases but not others could, over time, teach your brain to anticipate rewards for buying specific products while you’re shopping.

Dr. Banker adds that further research could be done to see if the study’s theories hold true at higher prices. It also could study consumers who tend to overuse or misuse credit cards, to understand further why they act as they do. This study focused on people who mostly paid on time and used credit cards appropriately. Understanding brain patterns for other types of consumers could help lead to solutions that attempt to pre-empt harmful spending behaviour, Dr. Banker says.

Reprinted by permission of The Wall Street Journal, Copyright 2021 Dow Jones & Company. Inc. All Rights Reserved Worldwide. Original date of publication: May 1, 2021



MOST POPULAR

BNW Developments has established a Sydney presence, joining Arada and Sobha Realty among the growing number of UAE developers pursuing Australian buyers and development opportunities.

The Australian leather house has opened an immersive four-day pop-up in Manhattan, unveiling its Bloom Collection and redefining what a product launch can look like.

Related Stories
Money
How Families Can Beat 7% Mortgage Rates and Lower Their Tax Bills
By Laura Saunders 09/10/2026
Money
The Stock Market’s Breezy Summer Is Over. Investors Beware.
By Hannah Erin Lang 08/09/2026
Money
The Sudden Unraveling of Wall Street’s Momentum Trade
By Gregory Zuckerman and Gunjan Banerji 31/08/2026

Strong family financial planning can help reduce taxes and support younger generations. From intrafamily loans and asset gifts to inheritance disclaimers, strategic cooperation can create meaningful financial benefits—when families have the trust and structure to make it work.

By Laura Saunders
Fri, Oct 9, 2026 4 min

Happy is the family whose members—parents, grandparents and grown children—trust each other enough to cooperate on shared goals, especially financial ones. When that is truly the case, Uncle Sam’s tax rules can help as well.

This matters especially now that mortgage rates are above 7%, and many families are looking for ways to help younger members. If the elders have resources and are confident younger ones can cooperate, a family loan could make homeownership possible while providing the elders with a useful income stream.

Other strategies can actually lower taxes, such as when funding 529 plans or Roth IRAs, or when someone inherits a traditional IRA with required withdrawals larger than they will need.

Here are three strategies useful for functional families.

Intrafamily loans

It is perfectly legal for families to lend money to a relative for a down payment or even a private mortgage.

But it is important not to cut corners, says Ryan McKeown, a CPA with Modern Wealth Enhancement in Minnesota. If the loan is for a down payment, be honest with the mortgage provider and have a formal agreement. The lender owes tax on the interest payments received.

If the loan is for a private mortgage, both sides should have legal representation with a formal written agreement, including payment terms. The lender owes tax on the interest, and the borrower often can deduct it if he or she itemizes.

To avoid IRS trouble, the interest rate shouldn’t be lower than the agency’s Applicable Federal Rate at the time of the loan. Currently that is about 5% for loans longer than nine years; about 4.5% for loans three to nine years; and about 4% for loans three years or less. Currently, traditional mortgage rates are generally above 7%.

In addition, the lender could use the $19,000 annual gift-tax exemption (described below) to forgive some or all of the interest or principal annually. If both lenders and borrowers are married, that is up to $76,000 a year. There is no tax for the borrower on such forgiveness, because it is from a gift.

If you’re going this route, McKeown advises against having a fixed plan to forgive the debt. Instead, do it in one-off letters specifying the amount—and keep careful records. Otherwise the IRS might try to treat the loan as a taxable gift.

Asset gifts

Powerful tax-saving moves for families often use gift-tax provisions. Under current law, anyone can give anyone else up to $19,000 of assets annually, free of gift tax. That means a married couple with three grandchildren could give them a total of $114,000 in 2026.

The gifts can be cash or other assets, like stock. For noncash gifts, the cost basis—which is the starting point for measuring taxable gain after a sale—“carries over” to the recipient. So if someone buys $1,000 of stock and gives it away when it is worth $5,000, the recipient’s cost basis is $1,000. If the recipient later sells the shares for $8,000, the taxable gain is $7,000.

Here’s an example showing how gifts could save a family taxes. Grandma is a widow of modest means, while her child and spouse have prospered. The couple has two children, and they want to contribute $5,000 to a 529 college-savings plan for each—but they need to sell stock to do it. Their tax rate on the sale would be 18.8%, and they would need to sell about $11,000 of stock.

However, Grandma’s federal tax rate on the stock sale is 0%. If the couple gives $10,000 of shares to Grandma, she could sell them, pay no tax, and fund the grandchildren’s 529 plans. This saves about $1,000 of tax.

These moves are legal, and they could be used in other ways, such as to help a young person fund a Roth IRA.

But trust among family members is essential: Under the law, givers can’t put conditions on a gift. Grandma could use her stock proceeds to take a cruise, but she makes 529 contributions instead.

Mark Sellner, a retired tax attorney and CPA living in Sarasota, Fla., uses this strategy. His children sell stock he gives them and fund 529 plans for his grandchildren.

The family’s tax savings aren’t huge, but he likes other benefits. The sales by his children don’t boost his adjusted gross income, which in turn could raise his Medicare Irmaa premiums or his 3.8% surtax on net investment income.

Sellner doesn’t worry about his children using the funds for another purpose.

“There can’t be any strings attached to gifts. Of course, it is up to us to decide whether to make them in the future,” he says.

Two caveats: The “kiddie tax” applies to most children under age 24, and it is levied at the parents’ rate on investment income above $2,700 in 2026. Consider this before making gifts to a young person.

Investors who give away stock also forgo the step-up, an important provision that exempts assets held at death from capital-gains tax.

Sellner knows he’s losing a step-up, but says, “The children could use a little more now. Why should they wait 20 years to get it?”

Disclaimers

A disclaimer is a highly useful strategy in which one heir renounces an inheritance in favor of another heir. Assuming family members cooperate, this can save taxes.

Here’s one example. Dad died and had a large traditional IRA that he left to Mom. She has enough assets and income to cover her expenses, and she lives in a state with a stiff estate tax. The inherited IRA would put her estate over the threshold.

Also surviving are three young-adult children. If Mom disclaims all or part of Dad’s IRA within nine months of his death, that amount could go directly to the children. They will have 10 years to empty the account, and the family as a whole will likely save estate and income taxes.

Disclaimers have many key details, especially regarding beneficiary documents. Although heirs have great freedom in choosing what assets to disclaim, the rules about who gets disclaimed property are rigid. It is best if the original owner names tiers of heirs so that if one disclaims, the next recipient is clear.