The researchers included neurobiologist Philippe Tobler, PhD, of the University of Cambridge.
"The rich are different from you and me," write Tobler and colleagues, quoting novelist F. Scott Fitzgerald.
Tobler's team studied 14 healthy adults who were 28 years old on average (age range: 20-44). All participants had completed college or were within two years of completing their college degree. They completed surveys in which they reported their financial assets and annual income.
Their average assets equal $1,691. Their average annual income translates to $20,238.
Participants saw a series of images on a computer screen. They could press a computer key to make some (but not all) of the images switch to a picture of a 20-pence British coin. The images kept changing and were shown for three seconds at a time. Participants had to quickly learn which images could switch to the picture of the 20-pence coin.
If they pressed the computer key when those images appeared, they earned a real 20-pence coin, which is worth 39 U.S. cents. If they goofed, they got no money.
The people with the most financial assets and highest incomes were slower to learn the money-making images than those who were less wealthy, according to financial surveys completed by participants.
During the test, the researchers scanned participants' brains with functional magnetic resonance imaging (fMRI). The brain scans show that richer participants had slower reaction times in brain areas related to reward than those who had lower incomes and fewer financial assets.
Age and education level didn't explain the results, note Tobler and colleagues.
Tobler's team also asked participants how often they would pick up a 20-pence coin if they found one on the street.
The researchers reason that "once very rich, one would less readily pick up a coin from the street than at the start of a financial career."
The study didn't include any moguls. But the findings suggest that that theory may hold for people without oodles of money.
Participants answered on a five-point scale, in which 1 meant they would never pick up a 20-pence coin on the street and 5 meant they would always pick up the coin. Participants with lower incomes were more likely to say they would pick up the coin, compared with richer participants.
Participants weren't followed over time. So it's not clear if changes in their bank accounts over time affected their test scores or their appreciation of small change.
The study appears in Neuron.
By Miranda Hitti
Reviewed by Louise Chang, M.D.
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