Preference by Association: How Memory Mechanisms in the Hippocampus Bias Decisions

Abstract

The Right Choice? So-called irrational decisions made by humans are popular fodder for “believe it or not” stories. But what's actually happening when we make choices that do not seem to be justifiable on purely economic or logical grounds? Presumably, we are not simply making errors; instead, our choices may reflect an internal bias that we are not aware of. Wimmer and Shohamy (p. 270 ) show how the hippocampus can instill an unconscious bias in valuations, whereby an object that is not highly valued on its own, increases in value when it becomes implicitly associated with a truly high-value object. As a consequence, we then end up preferring the associated object over a neutral object of equal objective value while not really knowing why.