N400 and the beautiful is good stereotype continued, results from my current research

In a previous post I described my current research in which I tried to measure the beautiful is good stereotype using EEG. The idea is that when we are presented with something that contradicts our stereotypes, our brain says "wait a minute, those just don't go together, that is odd". It just so happens that there is an ERP component, called the N400, which is sensitive to mismatching stimuli.

So in my experiment, participants were presented with faces rated as either attractive or unattractive, followed by words rated as either positive or negative. Their EEG (their brain activity), was measured throughout the experiment. We expected to find that the magnitude of the N400 wave/component would be larger when presenting incongruous face-word pairs. Pairs that are incongruous contradict the stereotype, so in this experiment it would be attractive faces followed by negative words or unattractive faces followed by positive words.

So what did we find? Do our brains object when they see an attractive person followed by a negative trait or when an unattractive face is followed by a positive trait. In our experiment we found no N400 for attractive faces, however, we did find a clear effect for the unattractive faces. This supports the view that rather than having a "beautiful is good" stereotype we have an "ugly is bad" stereotype. Just to spell it out, our data showed that when the average participant was presented with an unattractive face followed by a positive word, the brain responded with a larger N400 component, indicating that there was a mismatch between the two stimuli, they did not go together. According to our data, it is much harder to imagine an unattractive person with positive traits than an attractive person with negative traits...

Another discovery that we made during the study is that there was a difference in the EEG that depended only on the type of face presented, that is the EEG activity following presentation of an attractive face is different from the EEG activity that follows the presentation of an unattractive face. Interestingly, the difference in EEG activity following presentation of either attractive or unattractive faces is highly similar to the difference that you see when you present pleasant or unpleasant stimuli. So it would seem that perceiving an attractive face will "reward" your brain. This is also supported by fMRI studies in which it has been shown that perception of attractive faces leads to activity in parts of our brain normally associated with reward.

If you are still curious and want a more complete description of the experiment you can download the entire article here.

The next step in our research is to investigate further what types of positive traits are associated with attractive and unattractive faces. A previous meta-analysis have shown that we associated attractiveness more with social competence than with intellectual competence. We are going to see whether this pattern we will also see this pattern when we measure the stereotype using N400. Furthermore, we are going to see if there is a link to memory. One could speculate that it is easier to remember face-word pairs that agree with our stereotype because we already have a developed network to store such information (or something like that). Or, alternatively, perhaps we remember incongruous information better because when we see something that does not agree with our stereotype we use lots of resources to reconcile it with what we know, and since the level of processing of a stimuli is correlated with how well we remember it, it is possible that we will remember incongruous pairs better. We will see...