>> So when it comes to language development during infancy and toddlerhood,
I want to talk about a few things.
We'll talk about kind of some general stages of progression of language development.
We'll talk about some characteristics of language development,
some things that kind of are common occurrences.
We'll address milestones.
We will look at child-directed speech and briefly address some
of the theories surrounding language development.
So language tends to progress very similarly in all languages [inaudible],
and so it starts with just kind of making noise on purpose.
So gurgling, cooing, and then starting to turn take, right.
So I make a sound.
Then I'm quiet.
Someone else makes a sound.
Then they're quiet.
Then I make a sound again, and you can notice this within the first couple of months
that they naturally recognize this importance of turn taking, and about four to six months,
their vocalizations, and prior to this, their vocalizations include the sounds
that are necessary for any language.
[Cough] So we call them, you know, all the languages of the world at that point, right,
but as time progresses, that will get less and less so except for the sounds
that they hear made in live language.
Gestures do seem to be easier than vocalizations and can allow both babies that are hearing
and deaf to communicate, and so you will hear advocates,
people advocating for baby sign language, right, teaching them to use their bodies to communicate
because they have the ability to communicate before they have the ability to speak,
and about 10 months is kind of the stage of understanding, and I think it's important
to note that at all stages they understand more than they can communicate,
that that's really a period of a lot of receptive language growth.
At about 12 to 13 months, you'll start hearing speech and speaking very basic
with hollow phrases, so partial words to convey thoughts.
So, you know, we would say "juice."
They might just say "ju," and that means juice.
As they get older then that becomes more complete words,
but then they still use really limited words,
and by 18 months that might become telegraphic speech, which is where they combine two words
to communicate, so "baby bye-bye" could mean "the baby is leaving."
As I mentioned, babies use gestures before they use words.
So again, advocate-there's nothing wrong with teaching them signs as well.
Culture influences how language will develop,
especially when it talks-when it comes to what first words will be.
So in English we focus a lot on nouns, so things and people, and so often first words are nouns,
but in languages such as Chinese where the focus is verbs,
it's more likely that their first word will be a verb.
So instead of "doggie," it might be "helping" because the focus of language is different.
Vocabulary during this time period is experiencing a huge growth spurt, and,
as I mentioned, receptive language will always outpace expressive language.
This is still the case for you or I.
We could listen to someone talk about something and understand it but not yet be able
to speak the way they were speaking effectively because we can understand more
than we can produce, and children may also or children often go
through both under-extensions and over-extensions.
So under-excuse me [cough]-under-extensions are when only one type
of an object is considered that object.
So, but the example the book gives is the family's dog is the only thing
in the whole world that can be "doggie," but on the flip side, if the child recognizes
that four-legged animals that have fur are "doggies," they would over-extend
and include horses and cats and goats and sheep and cows as "doggies."
So there are some common things that happen in language.
So the milestones related to language development relate a lot to the stages
or progression that we mentioned, but I wanted to specify that out a little bit more.
So it starts with cooing and turning heads towards sound.
Then it turns to babbling.
So cooing tends to be what we refer to as verb based-not verb based, sorry, vowel based,
so very, you know, oh's and ah's.
Babbling is more of the consonant sounds, "dada," "mama," those types of things.
They start to make expressions with their face.
They cry in different ways to communicate different things.
By six months, they're responding to sounds by making sounds,
although I would say that happens earlier.
Stringing vowels together, responding to their name, and may use sounds to show joy
and displeasure, and brings in those jabbering consonant sounds.
By nine months, understands "no," but I do want to note understanding no and being obedient
to "no" are two completely different things.
I once had a mom ask me, you know, "When will she start-when will she understand what no is?"
And I said, "about the same time that she refuses to listen to what 'no' means."
[Laughter] Lots of different sounds at this age, copying sounds and gestures,
using fingers to point at things.
By a year, responding to those simple requests, making simple gestures like shaking their head
"no" and waving "bye-bye," may use different tones that sound more like adult speech,
may use words to refer to people and exclamations,
tries to attempt to use the words that you use.
Eighteen months, again, knows what those ordinary objects are, points,
uses kind of physical things to communicate.
You can see these overlap heavily with cognitive milestones, and by two years,
points to things that are named, says sentences with two to four words,
following simple instructions, pointing to things in a book, repeating words they overhear.
So part of speech for children is what we as adults do.
So you may have noticed and you may have done it,
that we tend to change the way our voice sounds when we're talking to babies.
So we do things like this.
We make our pitch higher.
We use a sing-song voice.
We make exaggerated sounds.
Our facial expressions change.
Why in the world do adults sound so silly when they talk to babies?
The answer is simple.
It works. It helps get their attention.
It helps them look at our face, [cough] and I want to note it's not the same thing
as baby talk when I'm saying "Oh, does baby want a baba?"
Right, we're actually using language or just kind of creating it in a way
that they pay attention to and that they can take in.
You might also have heard this called parentese.
So what are some of the theories behind language development?
So there's kind of two sides to this.
People like Noam Chomsky believe that infants had a neural device, so something built
into their brains, that allowed them to develop language, and it makes them ready
to learn language and that it happens no matter what language they hear.
There are others that kind of argue the other side, that children learn language
because they need to communicate and that they do so through hearing language of others.
I would happen to say that I think there's a little bit of truth to both.
I think there is-our brains are wired to learn language, but we have to hear language
and see a reason to use language in order for that to develop.