JOHN YANG: More than 90 percent of deaf children in the United States are born to hearing parents.

For them, the path forward isn't just difficult, it's controversial.

With the advent of cochlear implants, technology has the opportunity to change lives.

Yet many deaf advocates say not teaching sign language is a risky proposition.

Pamela Watts of Rhode Island PBS Weekly takes a look at the stark choices some parents face.

PAMELA WATTS: Jesus Flores was not diagnosed as deaf until he was three years old.

His mother, Marta Gomez, spent years trying to figure out why he wasn't communicating.

Doctors gave her a choice a cochlear implant or sign language.

They said -- MARTHA GOMEZ, PARENT: If you put a cochlear implant, Jesus can hurt.

Jesus want to talk, or you can leave it there and just do a sign language.

Of course I want to go to the side where he can talk, he can hear, because all my family can be like, good communication with him.

PAMELA WATTS: Jesus went through three surgeries for his cochlear implants.

He also went to a specialty school in Rhode Island that exclusively focuses on spoken language.

After seven years at the school, Jesus wasn't showing much progress.

MARTHA GOMEZ: And I'm asking for that second opinion.

And with the second opinion, they did tell us we got that wrong diagnostic.

PAMELA WATTS: It turned out Jesus had an auditory nerve problem that the cochlear implant would never have been able to resolve.

And how did you feel when you heard that?

MARTHA GOMEZ: Oh, my God.

My whole entire world is like everything is -- I cry.

I cry a lot.

I cry a lot.

And then when I decide to thinking about something else and we're talking about School of the Death.

PAMELA WATTS: At Rhode Island School for the Deaf.

DAVID MULLOWNEY, ASL SPECIALIST, RHODE ISLAND SCHOOL OF THE DEAF: What are we doing next?

PAMELA WATTS: Parents like Martha Gomez are learning American Sign Language or ASL together.

DAVID MULLOWNEY: The group hug is what this mouse needed.

PAMELA WATTS: David Mullowney is their teacher being interpreted aloud.

DAVID MULLOWNEY: This is a sign for I love you.

You'll see this a lot in American Sign Language.

PAMELA WATTS: Nancy Maguire Heath is the director here.

NANCY MAGUIRE HEATH, Director, Rhode Island School for the Deaf: We frequently, especially the last few years, have had number of students referred to us who have no language or have little language.

They may have 50 to 100 spoken words when they should have thousands by that age.

PAMELA WATTS: Most arrive never having learned any sign language.

NANCY MAGUIRE HEATH: You and I, because we're hearing, we learn from our environment all the time.

We learned from mom on the telephone, talking to the plumber.

A deaf child may not get any of that.

They're not getting that incidental learning that our brain grows from.

PAMELA WATTS: That brain growth is the focus of extensive research by Dr. Wyatte Hall, assistant professor of Public Health Sciences at the University of Rochester Medical Center.

DR. WYATTE HALL, Assistant Professor of Public Health Sciences at the University of Rochester Medical Center (through translator): We've seen a lot of research that there appears to be a critical period, or a sensitive period, depending on who you talk with.

That period is a time where we are born biologically ready to acquire language.

PAMELA WATTS: Studies estimate the window lasts from birth to ages three to five.

If children can't easily hear people talking or see people signing, they run the risk of developing what's known as language deprivation.

NANCY MAGUIRE HEATH: Their thinking becomes locked in the concrete.

They can keep learning, but they don't do well in the abstract, and they can't keep up.

WYATTE HALL (through translator): By the time the critical period is over, it's very difficult to go back and fill in the gaps for their language functioning and for their everyday use of language.

There is a very powerful, a very strong structure and system, both medical and education in our country that strongly support using spoken language only approaches.

PAMELA WATTS: Hall says less than 10 percent of deaf children in America learn sign language.

Jesus didn't start learning ASL until he was 11 years old at Rhode Island School for the deaf.

Where would you say he's in school now?

MARTHA GOMEZ: Way behind.

Elementary, like, way, way, way, way behind.

PAMELA WATTS: So he has to work harder?

MARTHA GOMEZ: So hard.

PAMELA WATTS: Hall says that language deprivation shouldn't happen to any child.

WYATTE HALL (through translator): We already know how to prevent these problems.

You give deaf children sign language, it's completely preventable.

I've seen problematic framings that options are framed as or that you have to pick ASL or English spoken language.

What I've also seen is it does not have to be that way.

It can be, and you can have ASL and English.

You can give all the options.

PAMELA WATTS: To prevent that language deprivation, more than 20 states across the country have passed laws to monitor deaf children's language development milestones.

Similar bills have been proposed in Rhode Island, but have not passed.

WOMAN: Good morning.

Good morning.

PAMELA WATTS: Another group of hearing parents.

WOMAN: If you've made a snowman with your child, you can explain the buttons.

PAMELA WATTS: Meet to learn sign language from David Mullowney, who is being interpreted aloud.

WOMAN: And there's more snow.

He sees more snow.

He's like, yes, there's more snow.

And he's excited.

PAMELA WATTS: He signs the picture book.

The Snowy Day.

WOMAN: So Peter was sleeping all night.

PAMELA WATTS: And teaches key vocabulary to parents.

WOMAN: Morning.

And then third sliding.

He's walking along, he sees a tree, looks up, and he's poking the tree.

Poking again.

PAMELA WATTS: So that they can sign bedtime stories to their children.

MAN: Pete.

Pete.

Pete got up.

He woke up.

He wake up, he woke up.

PAMELA WATTS: It's a familiar road for Gomez, who has been learning sign language for Jesus.

She says helps her get better.

MARTHA GOMEZ: I think we cooking together and I'm going to ask Jesus, had I signed this or had I paid this, like I tried.

PAMELA WATTS: So he's teaching you?

MARTHA GOMEZ: Yes.

He's my teacher.

And when I do it wrong, he laughs at me.

PAMELA WATTS: What do you say to him to keep him motivated?

MARTHA GOMEZ: I just show how much I love him.

And that's a matter of what happened.

He always got all my support.

PAMELA WATTS: And that's the approach.

Maguire Heath says all parents should take.

NANCY MAGUIRE HEATH: You're the oil that connects things.

You're the link that connects things for your child.

Accept your child as he is, she is.

Let them know that, and to give them every tool in the book, including American Sign Language, and they will let you know what works for them and what doesn't work for them.

And they will appreciate that.

You are open to all of that.

PAMELA WATTS: For PBS News Weekend, I'm Pamela Watts in Providence, Rhode Island.