Psychologists conducted four separate studies examining spending patterns across three payment methods—credit cards, gift cards, and cash. Results revealed participants exercised significantly greater caution when paying with cash compared to other methods.As reported by the Financial Times, Priya Raghubir of New York University and Joydeep Srivastava of the University of Maryland published their findings on the 8th in the Journal of Experimental Psychology: Applied. They ranked payment methods from relatively transparent (cash) to less transparent (credit cards and gift cards).The researchers sought to test whether "less transparent payment methods might be perceived as more like playing with money, thereby making spending feel easier." One study was disguised as a market research exercise. Investigators described a fictional restaurant and menu to participants. Half were told the restaurant accepted credit cards, while the other half were informed it accepted only cash.When participants knew they could pay by credit card, their planned spending on dining increased significantly. In another study, volunteers were asked to plan purchases for a celebratory feast. Researchers gave participants a shopping list and asked them to estimate total costs. Those planning to pay by credit card estimated an average feast cost of $175, while those intending to pay cash gave a more conservative upper limit of $145.There may be ways to curb this credit card spending spree. Researchers asked other volunteers to approach the same test from a different angle. They had to estimate the price of each individual item and then add them up. This time, credit card users made a lower estimate of about $135. Summarizing their findings, they concluded: "The more transparent the payment method, the greater the 'pain of paying.'"