When my babies were babies, I would find myself contemplating how much they understood about the people in their world and what they were feeling. I am lucky to see babies regularly in my clinic where I specialize in early parenting adjustment. I marvel at the emotional communication I see between babies and their mothers in these precious moments.

Understanding how others feel is critical to being a successful human. Our emotional intelligence allows us to empathize with and predict others’ emotions. Adults are able to distinguish between the subtleties of feelings such as joy and excitement or sadness and regret. But how well do babies and very young children do this?

Young children can often label their own basic feelings as happy, sad, scared, and mad. Some developmental experts believe that very young children are only capable of defining feeling good and feeling bad but nothing more nuanced than that.

A recent study published in Proceedings of the National Academy of Sciences found that the ability of babies and very young children to both understand emotional subtleties and link positive emotions to a source is much more advanced than thought. The findings add exciting information to what we already know about children’s developing emotional awareness.

A team led by Yang Wu at Massachusetts Institute of Technology played positive emotion vocalizations to babies and young children while showing them two photos: one that matched the sound and another that didn’t. Something funny was vocalized as “Ha-ha,” delicious was “Mmm,” exciting was “Whoa,” sympathetic was “Ohhh,” and adorable was “Aww!” Only positive emotions were included in the study.

The researchers began by looking at the responses of two to four year old children. The children were shown two picture cards, one that matched the vocalizations and one that didn’t. When the researchers observed that two-year-olds chose correctly at a rate that was higher than chance, they decided to look at what even younger children were capable of. In total, the researchers conducted five experimental tasks involving 32 to 48 children in each task.

To study what babies under two years of age were capable of, the researchers varied the original task. 12-month-old babies aren’t able to choose a picture to match sounds so instead the researchers used a gaze task. Gaze tasks are often used in baby research. Two images were flashed up on a screen. The researchers observed whether the baby’s gaze shifted to the image that matched the vocalization.

For example, if the images on the screen were a cake and a crying baby and the sound was “Mmm” if the baby shifted its gaze to the cake then it would show that the baby could identify the correct emotional sound with the probable source. More often than not, 12- to 17-month-olds could match the emotion and its source correctly. This means the babies in the study were capable of discerning between different types of positive emotions.

Another exciting finding related to the ability of babies to understand the causes of positive emotions. A separate task devised by the researchers measured to what extent babies might actively search for causes of an adult’s emotional reaction.

The task involved pairing the vocalizations “Mmm,” “Aww,” or “Whoa” with a toy that the baby had to search for in a box. The adult peeked through a peephole on the top of a box and made one of two vocalizations. The researchers then encouraged the babies to reach into a felt slit on the side of the box. From the felt slit the babies retrieved a toy that either matched or didn’t match the vocalization.

Half of the infants retrieved a stuffed animal and the others retrieved a toy fruit. In the second part of the task, half received a toy car and the others received a stuffed animal. Half the time the toy did not correspond with the adult’s vocalized reaction. The researchers wanted to know if the babies would put their hands back in the box and search for a relevant toy in this situation.

To the researchers delight, the babies did search the box again when they received the mismatched toy. When the toy did not match the vocalization, the babies searched the box longer than when the toy they received did match. The researchers suggest that this means the babies thought something did not make emotional sense and sought to correct it.

The study findings indicate that babies are able to figure more about emotions than we previously thought. It seems that by the age of two they understand there are different nuances of positive emotion. It seems possible that twelve to 17-month-old babies already know that emotions belong in a context. The researchers plan to look at this more closely and see what it means for social relationships.

What do you notice in your baby? How much do you think your baby knows about emotions?