how do babies learn language skills?

Guest blog post by Ravindhra G. Elluru, MD, PhD, division chief of pediatric ENT

I was solely responsible for taking care of our kids over a long weekend when my then 4-year-old walks up to me and says “you not in a good mood, you don’t have your happy face on.” I melted at hearing that cute little person, with that adorable tiny voice, make such an endearing and observant statement. In a single sentence this little human not only communicated a thought, but also expressed empathy and gave me a glimpse into their personality."

As adults we often do not appreciate the power of our communication skills, unless of course we accidentally say something inappropriate and get a few awkward looks. However, when our babies say their first words we rejoice, laugh, cry and break out our video recorders. A baby’s first words should be celebrated, because it is an incredible accomplishment. Now they can tell us what they want, why they are unhappy, and of course what does not suit their little (big) moods. 

So how do babies learn language skills, and what skills are age-appropriate?

The answer to the first question is quite complicated, but can be described in very general terms. When a baby hears a word, the sounds go into the ear and are converted into electrical impulses that are sent to the brain. The brain processes these signals, along with other visual and tactile signals that are coming into the brain at the same time and stores this information as a packet of data. To say this particular word, the packet of data is retrieved and then sent to another part of the brain that converts the information into movements of the tongue, mouth and diaphragm. As we get older, words can even have emotions attached.

The COVID pandemic has changed us all in many ways, but we are all resilient and I know we will persevere and become even stronger. I wonder how little babies will recognize smiles when the masks come off. Recently, I asked a 3-year-old girl what she wanted for Christmas. She thought about my question for a second, and then with poise and confidence replied “toilet paper.” I never thought this pandemic would have such a significant effect on the little ones."

The most important thing to remember about the process of learning speech is that babies learn by imitating their environment. This hard wires the process of retrieving the information stored in their brains and converting them into movements of vocalization.

Babies are thought to hear and respond to voices even before they are born. They begin to learn sounds, words, and pace and rhythm of language in utero. After they are born, they learn to imitate the facial and tongue movements of language by observing those around them. 

Babies with older siblings seem to acquire language skills sooner than families without older siblings. Equally interesting, babies who grow up in bilingual homes may develop expertise in one or the other language slower than babies that grow up in a monolingual home. Therefore, both the quantity and quality of spoken language in a child’s environment influences the rate of language acquisition. 

Given the complexity of verbal communication as described above and normal individual differences in our cognitive abilities and environmental exposures, it should be no surprise that there is quite a bit of variability in acquiring language skills. Are there factors that can delay speech development, beyond the normal range? The status of the babies hearing always comes up in the mind of concerned parents when there is a concern about speech development.

All babies born in the Unites States undergo a hearing test as a newborn, and if they do not pass this hearing test they are sent for further testing. 

Babies can develop ear infections early in life, and accumulate fluid behind their ear drums which can lead to a mild temporary hearing loss. Your primary care doctor can evaluate for fluid behind the ears by using an otoscope. Babies who have frequent ear infections or keep fluid behind their ear drums may have protracted periods of hearing loss which may contribute to speech delay.

Tongue mobility can also sometimes impede speech development, especially articulation.  Some babies are born with a thickened frenulum below their tongue that keeps them from readily moving their tongue. Your primary care doctor can again evaluate for this issue, and if a problem can refer your baby to have this frenulum clipped.

So, what is normal amount of speech for a baby of a particular age? 

There is plenty of normative data for age-dependent speech acquisition and other developmental milestones. One very good resource is the Centers for Disease Control and Prevention’s website. This resource in particular is filled with data, and even developmental milestone trackers that you can use on your smartphone. Another incredible resource is your primary care doctor, who can discuss any concerns during routine well-checks.

If your baby is meeting all the other developmental milestones (sitting up, crawling, walking, social interactions), maybe they just need some more time to develop age appropriate language skills. Talk to your baby and read them books. Work with them to imitate sounds, like the sounds of farm animals. After all there is nothing cuter than a little baby making cow, dog and chicken noises. Expose them to other kids, relatives and family members.

If you are concerned about your child’s speech development talk to your pediatrician. And at the end of the day, take plenty of video clips of the kids doing and saying silly things. These memories will not only warm your heart every time you see them, but will also serve as material for a good toast at their wedding.