top of page


Social interaction is the foundation for language, thought and reasoning. This is the core idea of Social Development Theory developed by psychologist Lev Vygtotsky.

Teaching individual speech skills step-by-step removes the social reasons for communication. When we ignore the social component, many children “stall out” in their communication development.


Understanding how children learn gives us direction for how to provide intervention for speech-language-communication delays. According to Social Development Theory:

Children learn how to learn from others before they even start talking. (Recent brain imaging studies have demonstrated how this works during Serve and Return interactions.)

As children learn to use words and sentences to communicate with others, they are also starting to use language to communicate with themselves. We often hear preschool and kindergarten children talking to themselves, describing and figuring out a challenging task.

At around the first or second grade level, children start to use their “inner speech” for what we call executive functions. These are the mental processes that help us do things like make and follow a plan, focus attention, remember, and think about more than one thing at the same time.


Vygotsky said that there are three zones of learning. Two of them are (1) what I can do myself and (2) what I can’t do. In between these two zones is the Zone of Proximal Development (ZPD).

Don’t you just love the terms professionals invent? They always have to sound so complex! I like to call the ZPD the Learning Zone.

The Learning Zone requires guidance from someone who has more skill or knowledge. This guide help the learner focus on the relevant parts of a task. A guide helps the learner use what is already known, then shows how to add the next level of difficulty to the task.

Guides go beyond just telling learners if answers are correct or incorrect. Guides help learners analyze what didn’t work and what corrections are needed. They encourage learners to invent new ways to apply the skill.

Guides talk about the important details, what happened, and why it happened. This guidance helps children develop their inner speech. Inner speech is where children learn how to self-regulate (e.g., plan, organize, control impulses) and become independent learners.

Understanding how the Learning Zone works helps us avoid a common mistake in speech-language intervention. We must avoid focusing too much on just saying words.

We must always include the social reasons children have for using their speech. When they learn to interact with others, children increase their opportunities to practice learning all throughout their day.

The better children get at social interaction, the better they get at learning.


Many people have heard of ABA, or applied behavioral analysis. This is an umbrella term for approaches that focus only on observable, measurable behaviors. Skills are taught using the ABCs of learning.

One widely used ABA-only program is called Discrete Trial Training (DTT). The therapist breaks tasks into small steps and carefully controls the antecedent-behavior-consequent to provide “errorless learning.”

I must digress and tell you the story of when I first started to wonder about errorless learning. When I was earning my bachelor’s degree, I took all the psychology classes in behavioral psychology that I could. I loved how it seemed to have answers for everything and organized learning into precise, observable patterns.

The professors for these courses used frequent quizzes as a learning tool. I was very good at reading material and answering factual questions. My high scores were very reinforcing to me. To this day I have not forgotten the answer to this question: Who developed the procedures for errorless learning?

Can you guess why I remember it? Yup. I made an error on that question.

The answer to the question is a guy named Terrace. He taught pigeons to peck at a red key to get food and not peck a green key. The errorless method resulted in faster learning than a method that allowed errors, and the skill lasted longer. It also had fewer side-effects, like making the pigeons mad (i.e., aggressive behaviors).

If the learner makes a mistake during DTT, it’s because the therapist didn’t structure the task correctly. ALL the control is in the hands of one person during this teaching interaction. There is no opportunity for the learner to develop or apply inner speech during this process.

That’s okay with behaviorists because they don’t believe in inner speech.

I remember one of my professors talking about Noam Chomsky’s theory of language development. Chomsky said people are born with a “Language Acquisition Device” in their brain that allows a child to hear spoken language, process it and put together their own language system.

This “device” was often referred to as the “little black box” in your brain. Nobody knew what was happening in there, but it was clear some kind of processing was going on. Chomsky was a big critic of behaviorists, who believe that all learning must be observable and measurable.

As my professor told us what to think about Chomsky’s theory, he wiggled his fingers by the sides of his head and said, “Ho ho. He even believes there’s this little black box in your head that magically makes language happen.”

I thought to myself, “He knows that’s a metaphor, right?” Over the years, it has seemed to me that the most dogmatic and outspoken advocates for DTT methods prefer literal thinking rather than metaphor.

Don’t get me wrong, I’m not saying to not use ABA methods. Behavioral methods are ideal for teaching specific behaviors. ABA-only programs can teach skills for toileting, dressing, brushing teeth and all the other tasks children need to help them be more independent. I especially want a trained behaviorist (a Board Certified Behavior Analyst or BCBA) on the team when children are using behaviors that are harmful to themselves or others.

Using ABA behavioral methods are important for speech-language pathologists. NDBI intervention programs use ABA as an essential component. It’s more challenging to apply the principles during a social interaction compared to using the principles in drills seated at a table. It’s worth it, though. Using ABA methods makes learning go faster and more accurately. Combining ABA with naturalistic methods provides more meaningful uses of language and speeds carry-over of skills. The combination of ABA with naturalistic and developmental intervention provides better outcomes than using any of them alone.


When choosing an intervention program, make sure the ABA component acknowledges that children think differently than pigeons. Children can’t learn language, communication and social interaction when it’s taught as isolated skills that don’t serve social purposes.

Children who don't learn through social interactions don't have the opportunity to develop effective inner speech. Their executive functions won't fully develop, so they'll have difficulty with tasks that involve planning, problem solving, and self-regulation. Speech-language pathologists who use a naturalistic developmental behavioral intervention (NDBI) can help you lay the foundation for your child’s future learning. An SLP can coach you on how to strengthen your child’s social interaction skills at any age. Your child’s speech and language skills will be stronger when they are built on this foundation.




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