Samuel McClure and his group at Princeton University conducted a fascinating study investigating the cultural influences on human perceptions and behavioral preferences. Briefly, they selected coke and pepsi (two nearly identical beverages relative to chemical composition) and conducted taste tests, while recording brain responses using functional MRI. The results were interesting:
a) Preference was split equally for Coke and Pepsi in absence of brand information. In other words, relying solely on sensory perception (ventromedial prefrontal cortex), there was no significant difference.
b) When subjects (with stated preference for Coke) were asked to choose between Coke labeled cup vs no label cup, there was distinct preference for Coke labeled cups (even if both the cups contained coke). Moreover in these subjects, additional areas of the brain including the hippocampus, midbrain and the dorsolateral prefrontal cortex exhibited activity, suggesting that they also play a role in modifying behavior based on emotions. On the other hand, subjects with preference for Pepsi did not show statistically significant brand influence. The Coke brand thus evoked relatively stronger emotional response.
The study was published in 2004 and can be accessed here.