Feeling happy, free, confused and lonely at the same time? Science may have a name for that now.
While only six basic "emotion categories" had previously been identified, researchers have published a new study detailing 15 other "compound emotions," CNN reported.
Looking at emotions like colors, the scientists worked with the six primary emotion categories, which are happy, sad, fearful, angry, surprised and disgusted. The emotions are based on the facial muscles people use when they express each feeling.
Publishing their findings this week in the journal PNAS, the researchers combined these basic emotions for new "colors," similar to the way red and blue mingle to make purple.
The newly identified emotions are much more nuanced, showing how "happily surprised" is different from "fearfully surprised" or "happily disgusted."
"The problem with that is that we cannot fully understand our cognitive system ... if we do not study the full rainbow of expressions that our brain can produce," said Aleix Martinez, an associate professor at Ohio State University, as quoted by CNN.
Scientists hope to use the new findings to better understand the human brain, which has remained a mystery while researchers tried to analyze it using only the six basic emotions. While whether facial expressions are learned or innate is still in question, but researchers believe a large part of expressing emotion must be biological since humans universally use the same muscles to show a certain feeling.
Future research will examine psychiatric disorders such as schizophrenia or PTSD as well as autism and other development disorders.
The study could also influence future artificial intelligence. Japanese engineers are looking to build a robot that interacts "naturally" with people and can act as companion to the elderly since the aging population has few young caretakers.
"In order to do that, you need to have a system that can recognize the expressions of the user," said Martinez, as quoted by CNN.
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