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Cheerleaders Make Fools of Our First Impressions

Credit: MN National Guard

Credit: MN National Guard

By Daniel Carragher

The “cheerleader effect” ­– the observation that people appear more attractive when they are in a group – reveals some quirks about how the brain processes complicated visual information.

Since our earliest days, we have been taught never to judge a book by its cover. Despite this timeless warning, we are all quick to judge others based upon their facial appearance. But this doesn’t make us terrible people. Rather, these trait judgments occur automatically.

The brain responds to the attractiveness of a face regardless of whether we are supposed to make attractiveness judgments or not. Of the many trait judgments that we make during first impressions, attractiveness is the only trait that is accurately shown in the face.

In contrast to the conventional wisdom that attractiveness is an extremely subjective judgment, there is actually a compelling case to be made that there are universal standards of facial attractiveness. Males and females make very similar attractiveness judgments, as do people from other countries and cultures. Furthermore, months-old infants spend longer gazing at attractive than unattractive faces, and attractiveness judgments made by children are very similar to those made by adults. While any two people might disagree about the attractiveness of a face, in general people show very high levels of agreement about facial attractiveness. Why do we all find the same faces attractive?

The similarities in judgments of attractiveness around the globe suggests that there might be an evolutionary basis for attractive facial appearance. The “good genes” theory of attractiveness suggests that we find particular traits attractive because they signal that a potential mate is healthy, and will pass their high quality genes to potential offspring. In keeping with this theory, sex-typical characteristics, left/right symmetry and a trait called “averageness” are highly attractive traits in faces. Importantly, these traits can also signal the health of an individual.

Sex-typical characteristics, such as a square jaw in males and high cheekbones in females, develop around puberty with increasing levels of the sex hormones testosterone and oestrogen. These masculine and feminine facial features are attractive because they both signal the sexual maturity of a potential mate. Additionally, facial symmetry signals a history of typical, healthy development that comes from having a strong immune system.

The final attractive trait, averageness, is perhaps the most surprising. Contrary to popular belief, faces with an average shape are relatively attractive. That’s not to say that average faces are the most attractive faces, but they are certainly more attractive than most. By digitally blending many faces together to create one average face, researchers have found that the average face is perceived to be more attractive than the individual faces used to create it! Average facial characteristics are attractive because they can signal that an individual has an immune system resistant to a diverse array of diseases and parasites.

Because sexual dimorphism, symmetry and averageness are all characteristics shown in the face, nearly all we know about facial attractiveness comes from asking people to view just one face at a time. Yet, in the real world, we often meet others for the first time in a crowded setting, like a busy restaurant or bar. Do we make the same judgments in these situations?

The need to consider the effect of external factors on attractiveness evaluations was highlighted in 2008 by the TV show How I Met Your Mother. In the show, Barney Stinson described “the cheerleader effect”, a phenomenon he said made women appear to be more attractive when they are in a group compared with when they are seen alone. At the time, such an effect was purely speculative.

It was not until 2013 that the cheerleader effect was first tested under scientific conditions using the definition offered in the TV show. Remarkably the study, published in Psychological Science (https://goo.gl/TMHfs9), found that faces were more attractive when seen in a group compared with when they were viewed alone – just as Barney Stinson had predicted.

Crucially, this finding represents an increase in attractiveness for the same image of a face. Therefore, any change to the attractiveness of the image could only have been caused by the presence of the other faces in the group.

Of course, the cheerleader effect is not limited to pictures of cheerleaders. Indeed, both women and men look more attractive in a group. Our research shows that the cheerleader effect increases the attractiveness of an individual by around 2%. Importantly, our work also shows that the effect applies to the vast majority of faces, including those who are attractive and unattractive, suggesting that the cheerleader effect is a widespread phenomenon.

My own research, published in Scientific Reports earlier this year (https://goo.gl/GMG66e), has shown that the increase in attractiveness remains the same regardless of where the face is located in the group image. This is particularly interesting because we often spend longer looking at visual information from the left side of space compared with the right. Furthermore, increasing the number of faces in the group does not change the size of the attractiveness increase. My research also shows that the increase in attractiveness even remains if the observer is given significantly more time to view the group image compared with the single photograph. Together, these findings demonstrate that the effect consistently occurs under a variety of conditions.

Why does the cheerleader effect occur so reliably? Studies suggest that the increase in attractiveness is not because an individual looks more friendly or likable in a group. Indeed, my own research has found that the same cheerleader effect occurs even if the group is only made of identical photographs of the same person.

Curiously, it appears that the cheerleader effect is the accidental side-effect of the way that our visual system processes complex scenes, like a group of faces. The world around us contains more visual detail than we could ever successfully process and interpret, so our visual system has developed a short-cut to deal with this complexity by automatically creating a summary of complex scenes. For example, rather than encode each blade of grass, we simply see a lawn. This same averaging process occurs when we see a crowd of faces.

A crowd of faces is quickly summarised to create a single average face. Interestingly, by digitally averaging a group of faces to create an average face, researchers have shown that people incorrectly remember having previously seen this average face. This finding suggests that they have created the average face of the group in their mind. Through this summary process, people can very accurately identify the average emotion shown by a crowd of faces. As it happens, this summary face has the average facial characteristics that are so attractive in faces.

The final consequence of rapidly summarising group images is that we are unable to remember information about each individual face in the group. Consequently, we remember individual faces from the group as being more like the group average than they truly were.

Understanding why the cheerleader effect occurs requires that we bring together these cognitive processes. An individual is more attractive in a group because they are remembered as being similar to the automatically created group average, which, thanks to its average facial characteristics, is highly attractive.

While a 2% increase in attractiveness might sound trivial, the cheerleader effect is important for two key reasons. First, the attractiveness of an individual activates a powerful positive stereotype that influences a number of important life outcomes. Attractive people get more votes in elections, get shorter criminal sentences and have more dating experience than less attractive individuals. Therefore, any phenomenon that can systematically influence the attractiveness of an individual is worthy of further study and consideration.

Finally, the cheerleader effect clearly shows that in addition to the biological characteristics of the face itself, external visual factors and basic perceptual processes can also influence attractiveness judgments. So far we have only investigated the cheerleader effect in relation to attractiveness judgments, but attractiveness is just one of many judgments that create our first impression. Attractiveness, trustworthiness, competence, intelligence and sociability are all positively related to one another. For example, attractive faces are usually also considered trustworthy.

While we still have much to learn about how the cheerleader effect can influence attractiveness, perhaps the most exciting findings will come from applying the same research ideas to the other trait judgments made during first impressions.


Daniel Carragher is a PhD candidate studying experimental cognitive psychology at Flinders University.