Infants Recognize Emotion in Each Other by 5 Months Old, Study Says

Infants can recognize emotion in other infants as early as five months old, according to a study recently published in the journal Infancy.

Ross Flom, a professor of psychology at Brigham Young University who led the research, reports that infants use affect or emotion to communicate to one another and to their caregivers.

"Newborns can't verbalize to their mom or dad that they are hungry or tired, so the first way they communicate is through affect or emotion," Flom said in a news release. "Thus it is not surprising that in early development, infants learn to discriminate changes in affect."

Previous studies on infant vocalization revealed that babies are able to match the emotions of familiar adults as early as six months old.

In the latest study, Flom and his team tested infants' perception of their peer's emotions by documenting a baby's ability to match a facial expression with a perceived mood of a baby on a screen. The results indicated that the babes were aware of the emotion displayed by other babies and were able to respond to the emotion accordingly.

For instance, if an infant was shown an image of a happy baby on a monitor, the infant was able to match the mood of the baby on screen with a happy facial expression of its own.

"We found that 5 month old infants can match their peer's positive and negative vocalizations with the appropriate facial expression," Flom said. "This is the first study to show a matching ability with an infant this young. They are exposed to affect in a peer's voice and face which is likely more familiar to them because it's how they themselves convey or communicate positive and negative emotions."

Flom worked with 40 infants from Utah and in Florida, where his colleague Lorraine Bahrick from Florida International University assisted with the research. Infants were placed in front of two monitors. One screen shows a smiling, happy baby, the other displayed a sad, frowning baby. When audio of a third, happy baby was played, the infant test subjects looked longer at the screen featuring the happy baby. When audio of a third, unhappy baby was played, the infants gazed longer towards the screen with the unhappy baby. The audio was not in synch with either of the videos.

"These findings add to our understanding of early infant development by reiterating the fact that babies are highly sensitive to and comprehend some level of emotion," Flom said. "Babies learn more in their first 2 and a half years of life than they do the rest of their lifespan, making it critical to examine how and what young infants learn and how this helps them learn other things."