Carl Jung, the Swiss founder of analytical psychology, called shame a "soul-eating emotion."
Following the Jungian model, author and shame expert Dr. Brene Brown has called the emotion the "swamplands of the soul" -- something that makes us see ourselves as defective and worthless.
People often confuse shame with guilt, but Brown says there's an important distinction between the two: Feelings of guilt revolve around "I did something bad," but shame has more to do with the feeling of "I am bad."
Shame has evolved to serve the important function of being a social defense, according to a study published last week in the Proceedings of the National Academy of Sciences.
This adds some nuance to the traditional belief that shame stems from a feeling of being deficient.
"We've been puzzled by these very prominent hypotheses in social psychology that shame really isn't about people's concerns over how others see them," Dr. Daniel Sznycer, a psychologist at the University of California, Santa Barbara and the study's lead author, told The Huffington Post. "It didn't make sense to us that shame would be completely divorced from concerns about the evaluations of others."
Similar to the way pain protects us from things that hurt us physically, shame may protect us from things that threaten our social identity, the research suggests.
In other words, "the function of shame is to prevent us from damaging our social relationships, or to motivate us to repair them," Sznycer explained in a statement. It makes us care what others think of us, and helps to us determine the "social cost" of a particular behavior or action.
There's a clear evolutionary advantage to securing positive relationships and being valued by others. Humans once lived in small, cooperative hunter-gatherer groups, Dr. John Tooby, an anthropologist at the university and a co-author of the study, said in the statement.
"In this world, your life depended on others valuing you enough to give you and your children food, protection and care," he said. "The more you are valued by the individuals with whom you live ... the more weight they will put on your welfare in making decisions. You will be helped more and harmed less."
To conduct the study, researchers created 24 fictional scenarios depicting behaviors or personal traits that could lead to social devaluation, such as physical weakness, stinginess and infidelity.
For each scenario, one group of participants was asked to rate how negatively they would view someone else if they performed that action or had that trait. Another group was asked how much shame they would feel if those things were true of themselves.
Participants reported devaluing themselves and others at nearly equal levels. Other emotions, like anxiety and sadness, did not have the same similarities in magnitude.
Cross-cultural similarities among the 900 participants in the U.S., Israel and India revealed that shame had a similar effect in different social contexts -- reinforcing the notion that it is a universal emotional experience.
"We observed precisely what you predict if the function of shame is to guide your choices to factor in the values of those you interact with," Sznycer noted in the statement.