When it comes to money, people aren’t pursuing stacks of green paper or a collection of copper disks—they’re interested in what those objects represent. The pull of money, the economy and most behavioral research agree, is symbolic.

But what if the medium of exchange—cash itself—can change the way people behave? A study to be published next month in the Journal of Experimental Social Psychology points toward that possibility. Its authors found, through a series of six experiments, that people who were prompted to think about money—literally just shown a picture of bills or coins—were more likely to conceal their emotions than those who viewed non-financial imagery. This study offers only the latest addition to the list of behaviors brought on by the mere thought of money.

The idea of making people think about money and then observing how they behave first popped up in recent literature in 2006, when Kathleen D. Vohs, a professor at the University of Minnesota’s Carlson School of Management, published “The Psychological Consequences of Money,” a paper describing what happened when subjects were primed with images of cash. Instead of relying on pictures, Vohs had some of her subjects unscramble phrases that included words such as “salary”; meanwhile, a control group dealt with non-monetary phrases.

The disparities that arose between the two groups as they went about various tasks were surprising. The non-money group spent an average of three minutes on a difficult puzzle before giving in and asking for help, while members of the money group tinkered away for more than five minutes. Members of the non-money group also spent about twice as much time helping a struggling peer with the puzzle than those in the money group.

Vohs employed other strategies of bringing money to mind, with similar results. People who stared at a money-related screensaver ended up seating themselves farther away from a later conversational partner. And subjects who had more money left over after a Monopoly game were less likely to help a passerby who dropped her pencils. Being exposed to money, Vohs and her co-authors concluded, made people less helpful. This is the case because with money comes a sense of self-sufficiency, they reasoned.

In 2012, a replication of the study failed to turn up the same results that Vohs found, but before then, a handful of other researchers had already started to investigate other possible effects of priming people with money. Even though this replication casts some doubt on Vohs's findings, these other researchers, some using Vohs's own priming method, have observed significant behavioral changes in their subjects.

Wharton’s Cassie Mogilner published a paper in 2010 comparing the results of priming people with money to when they were primed with time. People with time on their mind were more likely to prioritize social interactions, while the money group worked longer and socialized less. And in February 2013, a study in Marketing Letters observed that priming people with money made them more likely to buy a pack of batteries than a slice of cake—a choice the researchers took to mean that money-primed people to prefer utilitarian options over hedonistic ones. Three months later, another study came out suggesting that being exposed to money made people more likely to behave unethically; in these experiments, money-primed subjects were more willing to lie to make money in a simple game and were more likely to rate certain scenarios, such as swiping extra office supplies for personal use, as ethically permissible.

Which brings us to 2014. By now, research has indicated that simply thinking about money turns people into antisocial, unethical pragmatists who are unwilling to help strangers. The soon-to-be-published Journal of Experimental Social Psychology study suggests we should add “stoic” to that description. The study, devised by a team divided between three universities in Hong Kong, tracked the visibility of subjects’ emotions after they looked at pictures of money, seashells, furniture, or leaves. (Sometimes they unscrambled money-related sentences, just like in Vohs’s study.) When asked to perform various tasks—such as writing negative reviews on Amazon or describing a funny scene from a movie—subjects primed with money were more reluctant to express their emotions. The researchers theorize that thinking about money forces people into a business mentality, a mindset in which it’s considered advantageous to hide your feelings.

The strength of all of these findings about money-priming likely has a lot to do with where they were observed—the U.S. and Hong Kong are both highly commercialized, business-oriented countries. Cassie Mogilner, the Wharton professor who compared the relative influence of money and of time, pointed out that money is more prized in American culture than in European culture, which might explain why Europeans are generally more satisfied with the decisions they make about their work-life balance.

So, to temper the harmful effects of money-priming, one option would appear to be to systematically erase all traces of cash from our culture. Instead, more reasonably, we could start to think critically about the medium of exchange we're using at any given time. Cash likely has this effect on us because it so clearly communicates its own scarcity; sensing your spending is easier when you're physically getting rid of a bill. Credit and debit cards, though, don't bring about the same behavioral shifts that cash does, as a study published last year hints. Of course, credit cards come with their own pitfalls: using one made subjects in a 2001 study willing to pay roughly twice as much for the same item, compared to when they paid in cash.