Search Here

Seeing happiness in ambiguous facial expressions can reduce aggressive behavior in healthy adults and young people at high-risk of criminal offending and delinquency, according to a new study.

Researchers at the University of Bristol wanted to look at the relationship between recognition of emotion in ambiguous facial expressions and aggressive thoughts and behavior in healthy adults and adolescents considered to be at risk of committing crime.

The study published in the journal Psychological Science revealed that it was possible to modify biases in emotion recognition to encourage the perception of happiness over anger when viewing ambiguous expressions.  Researchers said encouraging people to see happiness in ambiguous facial expressions decreased the levels of self-reported anger and aggression in both healthy adults and high-risk adolescents.

The study consisted of 40 healthy volunteers and 46 adolescents aged 11 to 16 who were considered to be at high risk of committing crime and had a high frequency of aggressive behavior.

In the experiment researchers showed participants composite images of facial expressions that were happy, angry, or emotionally ambiguous and asked them to rate them as happy or angry. This first part of the experiment established a baseline balance point of how likely participants were to read ambiguous faces as angry.  Afterwards researchers told some of the participants that some of the ambiguous faces they had previously labeled as angry were in fact happy.

The study found that both healthy volunteers and at-risk adolescents trained to recognize happiness rather than anger in ambiguous faces reported lower levels of and aggressive behavior.

Researchers also ran another experiment on another set of 53 healthy volunteers.  Researchers wanted to see if perceptions of facial expressions could be changed without explicit feedback.  Past studies found that prolonged viewing of an image subsequently alters the perception of similar images. 

Researchers showed one group only angry faces and a control group a mixture of happy and angry faces.  They found that participants shown only angry faces subsequently shift their perceptions and became more likely to see happiness in ambiguous faces.  These participants also reported lower levels of anger and aggression.

"Our results provide strong evidence that emotion processing plays a causal role in anger and the maintenance of aggressive behavior. This could potentially lead to novel behavioral treatments in the future," lead researcher Professor Marcus Munafò said in a statement.