top of page


Babies have a super power that brings them the exact thing they need for growing their brain and learning new skills. What is that super power? Babies are irresistible.

Infants have features that adults are drawn to — big eyes, giggles, even their smell. Researchers at the University of Oxford in England used brain imaging to show that those features trigger the pleasure centers of the brain in both women and men. Babies use this super powered charm to lure us to them and keep us interacting with them.

Once we are hooked, we give babies the sights, sounds and touches they need for building connections in their brains. Harvard University’s Center on the Developing Child says the back-and-forth social exchanges that begin in infancy are “One of the most essential experiences in shaping the architecture of the developing brain.”

“Serve and Return” is the researchers’ term for the back and forth interaction between a child and adult. It’s the infant that starts this process, not the adult. This video demonstrates how Serve and Return builds a baby’s brain.


Brain cells, called neurons, are specially designed to transmit information. Electrical signals carry information between neurons at connections called synapses. Chemicals at a synapse build up as they are used more. These stronger connections form memories and help information flow more efficiently.

Sight, sound, touch, smell, taste — all the baby’s senses are stimulated by their contacts with us. All that information is exactly the raw material babies needs to build their pathways of synapses in the brain.

As children store memories, they build up their knowledge about the world. They are able to use their knowledge to get along in the world. They become more efficient learners as they collect these experiences and build their brain wiring. And all of this develops because of social interaction.

Babies start out with this inborn capacity to collect information and learn from whatever experience comes their way. During babies’ first three years, the synapses grow so rapidly they are said to bloom. By age three, babies have twice as many synapses as they will have as adults. Connections that are used the most become the strongest. As children grow, the synapses that aren’t used get pruned out.


During Serve and Return interactions, babies are learning about all the different purposes of communication. Think about playing peek-a-boo—what is a baby learning? “I like variety. I like a little bit of surprise. This person is a great toy. I like spending time with people. I can get people to keep doing things that I like.”

Babies learn the reasons to communicate through their social interactions. These reasons are why they continue to expand their skills in using words and sentences. It’s so they can keep meeting their social needs in more and more effective ways.

Here are some of reasons for communication. (Speech-language pathologists call them functions of communication.) See if you can think of an example of how a child who is not talking can express these functions of communication without using words.

request an object she sees a toy that she can't reach herself

request an activity he wants you to wind up a toy for him

protest an object there's a carrot on her plate

protest an action or activity you turned off the tv

request a social game he wants to play peek-a-boo

request comfort she pinched her finger in a toy

It’s essential that we respond to the meaning of a child’s interactions. When you respond, it increases the chances that the child will continue to use these reasons for communicating.

Responding to the child’s meaning means you follow through on what they communicate. You play the game, help the sore finger, or turn on the toy. You can also model (use) a word the child might use in the situation, like “more” or “owie.” Children learn to use the words after they learn the meanings through their social interactions.

These reasons to communicate get stronger as people respond to their meaning. The opposite is also true. If we do not consistently respond to the meaning expressed in nonverbal ways, a child’s reasons to communicate don’t develop fully. Let’s say we start out by emphasizing only one function – requesting for example. Children can learn to get food and other essentials by using certain actions or sounds. They don’t learn, though, how rewarding it is to interact with people for all the other social reasons. And that limits their learning opportunities.

Serve and Return interactions teach babies how to learn from other people. From this foundation, children continue to learn more advanced skills like talking and reading and writing. None of those skills will develop as well if a child doesn’t first develop the social learning foundation that is present in every Serve and Return interaction.


There’s an old saying, “It’s not what you said, it’s how you said it.” It doesn’t matter how many words you know if nobody wants to listen to you or if you don’t make sense. No matter what stage of communication development you are at — if you are using single words or 20-word sentences — it’s your social communication skills that determine how successful you are in accomplishing your purpose.

Here are a few of the social communication skills that babies start learning as soon as they lure you in with their cooing and big eyes and baby smell. Let’s trace a few of them to see where they lead.

look at the person’s face

look at what the other person is looking at

tone of voice and intonation are important

people know what I want when I do this (actions and sounds represent an idea)

I enjoy spending time with people

I can get people to spend more time with me (conversations)

Let’s see what that baby gaze develops into. Babies focus on things close in front of them. When you hold them close, they stare at you. You look back and talk. Over time, a baby learns to watch faces when they hear talking noises, even when you are farther away. Orienting to your voice becomes a habit, and this continues into adulthood. An important part of being a good listener is watching the speaker.

Where does learning words start? The baby cries and someone comes. While the adult is taking care of the need, he or she is talking. Through Serve and Return interactions, over time the baby starts to understand a word associated with that need. More time passes, and the child learns, “Hey, I know what she means when she makes those sounds.” After more Serve and Return, the baby starts trying to make those sounds. “Hey, that gets faster results than crying—I get exactly what I wanted on the first try!”

Here’s an important point though—We’re not just talking about learning words. “People know what I want when I do this.” A baby can learn, “When I cover my face with this blanket, Mom knows I want to play. Mom knows that I want to spend time with her, that I enjoy her company.”

Later, children learn more ways to start an interaction or keep it going. They use words to get a person’s attention, to start a conversation or keep it going, or to express how they feel. They are only going to get really good at using all the social reasons to communicate if they’ve had a solid foundation of Serve and Return interactions along the way.

“I enjoy spending time with people” is a powerful thing for children to learn. The most effective way to increase how long young children stay in any activity is to strengthen that feeling of, “Hey, I like it when we’re doing things together. I’m going to try this again because something good will probably happen.”

When children learn that good things happen by spending time with you, you can introduce new activities more easily and get them to stay in activities for longer and longer periods of time. And staying in those interactions with you is where new learning takes place.

Some children have a hard time staying in an interaction. They don’t want to stay in one place long enough to get dressed. They won’t look at more than a couple pages in a book. They move from one thing to the next after a few seconds. They might move away because it is difficult to tolerate some sounds, touches or movements. Adults need to start where the child is at, observe what helps the child be comfortable, and do a lot of that. WARNING! If your child resists and struggles during an activity assigned by your therapist, STOP doing it. You are teaching the opposite of staying in an interaction, Ask your therapist to help observe for activities that help your child want to stay with you longer. Use those as a starting point and gradually add in more challenging tasks.

These early stages of starting and continuing interactions lead to much more. A child who wants to get people engaged and keep them engaged is much more motivated to learn social communication skills like how to greet people, how to start a conversation, how to keep a conversation going, or how to stay on another person’s topic. Without that motivation, they miss out on many learning opportunities in their day.

Effective communication means more than saying lots of words and saying them clearly—although that is part of effective communication. It also means using all the reasons for communicating and using them in socially expected ways.

I’ve often heard the concern from parents and professionals that, “He’s learned to use X many words to request things he wants, but it just hasn’t carried over. He doesn’t initiate requests, or make comments about what he’s looking at.” This is a great example of how easy it is to overlook the importance of social communication. Just because he has a word doesn’t mean he knows how to use it for more than one reason,

When we are teaching specific skills, like saying words, we have to show the child how to use words in many different situations for all those different reasons to communicate. The best way to do that is during your regular, daily interactions.

Whether your child is verbal or nonverbal, you want them to be able to use all those different reasons to communicate. Those reasons give their developing speech-language skills a social scaffold to build upon. They can express their ideas with gestures or single words, and later with two-word combinations. Later, those same reasons are the motivations they will have for using sentences, engaging in conversations, developing friendships, and learning about reading and writing.


Serve and Return does work for children with delays, but it works less efficiently. Most children with delayed speech-language have had the typical amount of Serve and Return interactions. SPEECH-LANGUAGE DELAY IS NOT THE PARENT’S FAULT! The child’s neurons are not processing the information in a typical way.

You can help with delayed language, though, when you understand how Serve and Return works. You can use strategies that give your child MORE of these learning opportunities every day. The strategies can help FOCUS your child on the most important information in a social exchange, so he or she gets more useful information out of your interaction.

When you use strategies, your child gets the most out of those their social learning opportunities. At whatever age and whatever stage of development your child is, he or she can learn to be a more effective communicator.


Brain imaging studies are helping to explain what scientists have observed over many decades of directly observing children’s development. These researchers in child development—including speech-language pathologists and psychologists—have identified stages of development for infant and child learning.

I've made a three-page chart that identifies children’s stages of communication development from birth to the time they start making two-word sentences. There are several activities at each stage, with examples of how you can match your teaching strategies to the child’s level. You can download the pdf here.

If we are talking or playing too far above their level, children will not be able to use much of the information we are providing. To be effective coaches for a child, we must first be good observers.


Is it too late to use Serve and Return and specialized teaching strategies if your child is beyond the first three years when the neural pathways are developing so rapidly? Definitely not! Brains continue to develop into adulthood and learning is a lifelong process.

When a child is older or is delayed in development, it means that he or she needs even more focused attention during our Serve and Return interactions. Adult strategies have been demonstrated to accelerate children’s learning of communication.

These research-based strategies help you set up interaction situations that give your child the best opportunities for learning. The strategies help your child pay better attention to the skill that you are using and help you give feedback that encourages him or her to use the skill more often.


I always start with parents by teaching two strategies—matching and waiting. You can learn about these two strategies in my free online course, Boost Your Child’s Speech and Language.

Another source is this pdf from Harvard’s Center on the Developing Child. The two-page handout gives examples of how to support your child’s development using Serve and Return interactions.

Parent strategies are used in several research-based intervention programs that are carried out by speech-language pathologists and other child development professionals. If you would like to read more about some of these program, follow these links. (Full disclosure: Some of these links take you to Amazon, where I earn a small fee if you make a purchase.)




Joyce is very knowledgeable. Not only as a speech therapist but also on how the school system works. Which is very helpful going through the IEP process. She was able to engage with my daughter and was never hesitant to help in any way. I would definitely recommend Joyce to anyone that is looking for a trustworthy, caring and informed speech therapist.

bottom of page