We all know first impressions are highly influential, despite being told not to judge a book by its cover. A person's face can reveal a wealth of information ranging from their personality to their health. Now, researchers at the University of Toronto suggest social class can be accurately predicted by looking at someone's neutral facial expression.

The ability to read a person's social class was found to apply to their neutral face and not when people were smiling or expressing emotions. This suggests the first impression we give off, based on our neutral facial expression, is going to influence our interactions and the opportunities we have. The researchers believe the emotions reflected in our neutral state are linked to lifelong habits that have become etched in our face from our late teens or early adulthood.

Read More: Facial Expressions May Reveal Health Status

"Over time, your face comes to permanently reflect and reveal your experiences," said Nicholas Rule, co-author of the study published in Journal of Personality and Social Psychology, and associate professor at U of T, in a statement.

To draw this conclusion, Rule and Thora Bjornsdottir, a PhD candidate, used two groups of students.

First, one group was divided by annual family income: $75,000 was used as a benchmark; under $60,000 (poor); and above $100,000 (rich). The participants were photographed with their neutral facial expression. Following, another group of students looked at the photos and decided which ones were "rich or poor" just by looking at the faces.

This group was able to determine which student belonged to the rich or poor group with over 50 percent accuracy, which exceeds random chance. The results were not influenced by race, gender, or how much time students spent making their decisions. The researchers focused solely on neutral faces, because facial expressions like smiles or frowns can influence readings.

Rule concluded students who are just 18 to 22 years old have acquired enough life experience that it has physically influenced the shape of their face to the extent it reveals their socioeconomic status.

However, Rule and Bjornsdottir remain unclear how viewers make these judgements.

"People are not really aware of what cues they are using when they make these judgments," said Bjornsdottir. "If you ask them why, they don't know. They are not aware of how they are doing this."

We do know there are neurons in the brain that specialize in facial recognition, and therefore, when we look at someone, their face is the first thing we notice. This allows us to make immediate impressions of people, even if they have no basis in reality. Facial bias affects who we vote for, date, hire, prosecute, and convict, among many others.

Although first impressions predicted social class over half the time in the new study, facial bias can lead us to believe false insights or emphasize real ones. For example, a 2014 study in Trends in Cognitive Sciences found we tend to judge criminality and remorsefulness based on faces. Defendants who had certain facial characteristics, like appearing trustworthy or "baby-faced", were less likely to be convicted of a crime than those who lack these characteristics.

Read More: Fearful Facial Expressions Are Powerful Social Cues

It seems our expectations can lead us to influence people to behave in ways that conform to those expectations. For example, if we consistently think of our blonde friend as having more fun, they may end up behaving that way. In regards to the new findings, the relation between facial cues and social class may provide clues into poverty cycles and social classes.

However, the results should be approached with caution. The study did not take into account that family incomes can change over time and average income can differ significantly from place to place. Rule and Bjornsdottir seek to study older age groups to determine if patterns of facial cues can become even more apparent to people over time.

The truth is the definition of what we consider "being rich" and "being poor" is subjective and influenced by our own personal experience. Therefore, facial cues are not a foolproof tool to use to determine socioeconomic status.

But, our neutral facial expression seems to have more significance in people's first impressions of ourselves than we think.

Source: Bjornsdottir TH and Rule NO. The Visibility of Social Class From Facial Cues. Journal of Personality and Social Psychology. 2017.

See Also:

This One Facial Expression Can Permanently Damage A Relationship

Immigrants Show More Positive Facial Expressions To Overcome Language Barrier