Irving Kirsch’s (Harvard Medical School lecturer & Associate Director of Program Placebo Studies @ Harvard) Response Expectancy Theory is based on the idea that what people experience depends partly on what they expect to experience. This is the process that can at least partly explain what lies behind the placebo effect and hypnosis. The theory is supported by research showing that changing people’s expectancies can alter physiological responses. The theory has been applied to understanding pain, depression, anxiety disorders, asthma, addictions, psychogenic illnesses, and food hedonics.
Food perception and Response Expectancy Theory
How we perceive taste and flavor can be influenced by suggestions and expectations. Yeomans et al. (2008) looked at expectations about food flavor by using an unusual flavor of ice cream- smoked salmon ice. One group ate the ice cream from a dish labeled ice cream and another group ate the ice cream from a dish labeled frozen savory mousse. The experience of the food in the mouth generated strong dislike when labeled as ice-cream, but acceptance when labeled as frozen savory mousse. Labeling the food as ice-cream also resulted in stronger ratings of how salty and savory the food as compared to when it was labeled as a savory food. The individuals that ate the frozen savory mousse found the ice cream less salty and bitter, and found its overall flavor more pleasant. Thirty- nine patrons attending a prix–fixed dinner at a university–affiliated restaurant were given a glass of either North Dakota–labeled or California–labeled wine with their meal. The amount of leftover food and wine was measured. Those whose wine was labeled from California consumed 12% more of their entrée and consumed a greater weight of wine and entrée combined compared to those served North Dakota–labeled wine. The researchers concluded that not only does taste expectation influence one's taste ratings of accompanying foods, but that it also influences consumption of accompanying foods (Wansink et al., 2007).
At a cafeteria in Urbana Illinois 175 people were given a fee brownie dusted with powdered sugar (Wansink, 2006). They were told the brownie was a new dessert that may be added to the menu. They were asked how well they liked the flavor and how much they would pay for it. All of the brownies were the same size and had the same ingredients. However, the brownies were served on a china plate, on a paper plate or on a paper napkin. Those who received the brownie on a china plate said the brownie was excellent. The people eating the brownie from the paper plate rated the brownie as good. Those who were served the brownie on a napkin said it was okay but nothing special.
Individuals eating from the china plate said they would pay $1.27 for the brownie, while those eating from the paper plate said they would pay 76 cents, and those eating from the napkin said they would pay 53 cents. In a classic study conducted by Allison and Uhl (1964) college students who claimed to be “brand loyal” beer drinkers were asked to rate a number of unlabeled beers. Once the labels were removed and the beer was poured into a glass the “brand loyal” participants didn’t do very well picking out their favorite beer. Quite often we taste what we expect to taste, good or bad.
References available upon request