Counterfeit

To learn more, Rotem Botvinik Nezer at Dartmouth College in New Hampshire and her colleagues delivered moderately painful heat to nearly 400 people’s fingers via an electrode, allowing them to become familiar with it. They then applied two creams to different fingers of each person’s left hand. One was labelled “Prodicaine, an effective pain-relieving drug and the other “a control cream with no effects” The two creams were, in fact identical, with neither containing a pain-relieving drug.

Before receiving the Prodicaine cream, participants watched a short video on how to use it, along with a counterfeit testimonial about how effective it is. They were also told about its potential side effects. The researchers then reapplied the heat, this time alongside painful pressure. During this, they scanned participants’ brains via magnetic resonance imaging(MRI). People reported feeling less pain in the fingers treated with the Prodicaine cream than in those treated with the cream labelled as a control. The Prodicaine cream not only influenced their perception of the heat pain that they had become somewhat accustomed to, but also of the new pain from pressure.
–New Scientist