Antonio Rangel and colleagues at California Institute of Technology thought the perception that higher price means higher quality could influence people, so they decided to test the idea.
They asked 20 people to sample wine while undergoing functional MRIs of their brain activity.
The subjects were told they were tasting five different cabernet sauvignons sold at different prices.
However, there were actually only three wines sampled, two being offered twice, marked with different prices.
A $90 wine was provided marked with its real price and again marked $10, while another was presented at its real price of $5 and also marked $45.
The testers' brains showed more pleasure at the higher price than the lower one, even for the same wine, Rangel reports in this week's online edition of Proceedings of the National Academy of Sciences.
In other words, changes in the price of the wine changed the actual pleasure experienced by the drinkers, the researchers reported.
On the other hand, when tasters didn't know any price comparisons, they rated the $5 wine as better than any of the others sampled.
"We were shocked," Rangel said in a telephone interview. "I think it was because the flavor was stronger and our subjects were not very experienced."
He added that wine professionals would probably be able to differentiate the better wine — "one would hope."