Why first impressions are so persistent

"Imagine you have a new colleague at work and your impression of that person is not very favourable" explains lead author Bertram Gawronski, Canada Research Chair at The University of Western Ontario. "A few weeks later, you meet your colleague at a party and you realize he is actually a very nice guy. Although you know your first impression was wrong, your gut response to your new colleague will be influenced by your new experience only in contexts that are similar to the party. However, your first impression will still dominate in all other contexts."

According to Gawronski, our brain stores expectancy-violating experiences as exceptions-to-the-rule, such that the rule is treated as valid except for the specific context in which it has been violated.

To investigate the persistence of first impressions, Gawronski and his collaborators showed their study participants either positive or negative information about an unknown individual on a computer screen. Later in the study, participants were presented with new information about the same individual, which was inconsistent with the initial information. To study the influence of contexts, the researchers subtly changed the background color of the computer screen while participants formed an impression of the target person.

When the researchers subsequently measured participants' spontaneous reactions to an image of the target person, they found the new information influenced participants' reactions only when the person was presented against the background in which the new information had been learned. Otherwise, participants' reactions were still dominated by the first information when the target person was presented against other backgrounds.

Although these results support the common observation that first impressions are notoriously persistent, Gawronski notes they can sometimes be changed. "What is necessary is for the first impression to be challenged in multiple different contexts. In that case, new experiences become decontextualized and the first impression will slowly lose its power. But, as long as a first impression is challenged only within the same context, you can do whatever you want. The first impression will dominate regardless of how often it is contradicted by new experiences."

According to Gawronski, the research also has important implications for the treatment of clinical disorders. "If someone with phobic reactions to spiders is seeking help from a psychologist, the therapy will be much more successful if it occurs in multiple different contexts rather than just in the psychologist's office."

The research, co-authored with Robert Rydell, Bram Vervliet, and Jan De Houwer, is published in the latest issue of the Journal of Experimental Psychology: General.