ATLANTA, Ga. — Is your friend in a state of sheer delight, or intense fright? The ear-ringing sounds some people make apparently make it hard to tell. A new study finds most people can’t tell the difference between screams of joy and screams of terror.
Researchers from Emory University say screams of happiness are often interpreted as screams of fear because both have similar acoustic features. People use screams to express a range of emotions, from happiness, to excitement and surprise, to anger, frustration, and fear. Most of the time, it’s pretty clear which one of these feelings a person is trying to communicate.
However, it appears screams of joy are much harder to decode if you don’t have any additional context. Study authors suggest the confusion may stem from ancient times, when making the right call was the difference between life and death.
“To a large extent, the study participants were quite good at judging the original context of a scream, simply by listening to it through headphones without any visual cues,” says Professor Harold Gouzoules in a university release. “But when participants listened to screams of excited happiness they tended to judge the emotion as fear. That’s an interesting, surprising finding.”
Some screams are easier to figure out than others
Unlike speech, the study finds screams lack distinctive and consistent acoustic parameters, which make them harder to identify. To see whether people could do so, researchers asked 182 participants to listen to 30 screams from Hollywood movies through headphones. Each scream communicated one of six emotions: anger, frustration, pain, surprise, fear, and happiness.
After hearing each howl, listeners then rated on a scale of one to five how likely the scream was associated with one of these six feelings. The results reveal participants correctly paired screams and emotions in most cases, except when it came to happiness. The group often confused these screams with fear.
“The acoustic features that seem to communicate fear are also present in excited, happy screams,” Prof. Gouzoules explains. “In fact, people pay good money to ride roller coasters, where their screams no doubt reflect a blend of those two emotions.”
Similarities between cries of joy and terror could have deep evolutionary roots, the researchers add.
“The first animal screams were probably in response to an attack by a predator,” the professor of psychology says. “In some cases, a sudden, loud high-pitched sound might startle a predator and allow the prey to escape. It’s an essential, core response. So mistaking a happy scream for a fearful one could be an ancestral carryover bias. If it’s a close call, you’re going to err on the side of fear.”
The researchers started researching the screams of non-human primates decades ago. While most animals only scream when faced with a predator, some monkeys and apes use it to recruit support when fighting with other group members.
“Their kin and friends will come to help, even if some distance away, when they can recognize the vocalizer,” Prof. Gouzoules notes.
Some reasons people scream are still a mystery
Study authors then turned their attention to humans, collecting a large database of screams from Hollywood movies, TV shows, and YouTube videos. Those included classic performances by “scream queens,” like Jaime Lee Curtis, along with non-actors reacting to actual events. For example, a woman shrieking in fear when a meteor exploded over Russia or a little girl squealing after opening a Christmas present. The findings could explain why young children sometimes scream while playing, which remains unexplained.
“It’s just speculative, but it may be that when children scream with excitement as they play, it serves the evolutionary role of familiarizing a parent to the unique sound of their screams,” the researcher continues. “The more you hear your child scream in a safe, happy context, the better able you are to identify a scream as belonging to your child, so you will know to respond when you hear it.”
Previously, researchers measured the tone, pitch, and frequency of screams from a range of emotions.
“Our work intertwines language and non-verbal communication in a way that hasn’t been done in the past,” Prof. Gouzoules concludes.
The findings appear in the journal PeerJ – Life & Environment.
SWNS writer Tom Campbell contributed to this report.