Scientists from the Ohio State University discovered that humans have 21 different emotional facial expressions developed a way for computers to identify humans' emotions in the brain.
Led by Aleix Martinez, a cognitive scientist and associate professor of electrical and computer engineering at the Ohio State University, researchers found out that humans have "compound emotions" such as "happily disgusted" or "sadly angry."
"That is simply stunning. That tells us that these 21 emotions are expressed in the same way by nearly everyone, at least in our culture," Martinez said in a press release.
The research team carried out the study by consolidating 230 volunteers--100 male and 130 female. They photographed their facial responses to verbal cues like "you smell a bad odor" ("disgusted") and "you just got some great unexpected news" ("happily surprised"). In the 5,000 captured images, scientists observed prominent landmarks for facial muscles such as the outer edge of the brow and corners of the mouth. They used psychologist Paul Ekman's method called Facial Action Coding System (FACS)-- standard tool in body language analysis.
The resulting computational model will aid in mapping emotions in the brain. It is also a potential help to the diagnosis and treatment of mental conditions such as autism and post-traumatic stress disorder (PTSD).
Cognitive scientists will continue to determine the link between facial expressions and emotions and the genes, neural and chemical pathways that govern them.
"For example, if in PTSD people are more attuned to anger and fear, can we speculate that they will be tuned to all the compound emotions that involve anger or fear, and perhaps be super-tuned to something like 'angrily fearful'? What are the pathways, the chemicals in the brain that activate those emotions? We can make more hypotheses now, and test them," he explained in the press release. "Then eventually we can begin to understand these disorders much better, and develop therapies or medicine to alleviate them."
This study was published in the April 1 issue of the Proceedings of the National Academy of Sciences.