(Psychologytoday) - If I give you two glasses of wine and tell you that one costs $50 a bottle and the other $10 a bottle, which one are you more likely to say tastes better? As plenty of studies have shown, the $50 wine is probably going to win the taste test, and that’s true even if both glasses are really the same wine. A new brainimaging study shows that this is more than a matter of preference: Our brain is wired to fall for the trick.

Study volunteers were first shown bottles of wine with the prices clearly marked, and then given a small amount to drink while they were in an MRI scanner. For each wine, they were asked to rate the taste on a nine-point scale. The wine prices shown to the participants ranged between 3 to 18 euros (the equivalent of about $4 to $22), but in reality, all of the wine was the same and cost about $14.

As predicted, the volunteers rated the allegedly higher-priced wine as tasting better than the allegedly cheaper wine. The MRI scan showed that when those evaluations were made, two parts of the volunteers’ brains experienced greater activity—the medial pre-frontal cortex and the ventral striatum. That’s important because those two areas are especially involved in evaluating expectations and seeking rewards. When we see a higher price, our brain links the price to greater expectation of reward, which changes our perception—in this case, taste.