(BEGIN VIDEOTAPE)

GUPTA (voice-over): This is Amanda Baggs, rocking back and forth. She does not make eye contact. Her movements are erratic. Her behavior eccentric. She can not speak. And for most of us, this is precisely what we expect when we see a person with autism.

But Amanda will absolutely change your expectations. Would you define yourself as an autistic person, Amanda? As you'll see, Amanda has a lot to say. Her brilliance is laced with a wry sense of humor. We first came across Amanda on YouTube. Her appearance there so startling, I wanted to meet her. I had so many questions.

AMANDA BAGGS (through translator) : The way I naturally think and respond to things looks and feels so different from standard concepts or even visualization that some people do not consider thought at all. It is only when I type something in your language that you refer to me as having communication.

GUPTA: Amanda calls herself bilingual. For other autistic people, she has movements and gestures to communicate. But for the rest of us, she made this video to teach us how it works.

She jokingly calls us neurotypical, meaning we do not have autism. She communicates with the keyboard and her computer. And for visitors, a voice synthesizer.

So you've seen the video with your own eyes. I want to show it to you through Amanda Bagg's eyes. She lives in this building and she lives alone.

This is where Amanda made the video. She shot it, edited, and posted it on the Internet, all completely on her own. Surprised? If we must label her, she won't like it, but medically, she is a low- functioning autistic. . Part of the reason people watched it was because they were so stunned that a person who carries this label of autism, who doesn't speak, could put together such an astonishing video.

BAGGS: I put together several videos before and not a lot of people watched it.

GUPTA: But this time, she got through. Amanda, when you hear about people with autism that are institutionalized, that no one has really ever made a concerted effort to try and reach out to to communicate with in some way, what do you say to those people?

BAGGS: Everyone interacts with this society. And if you shut off from interacting with society, then you shut it off because it sure doesn't seem to me that I've ever seen someone who doesn't interact with society. GUPTA: In fact, Amanda interacts with everything around her. What about this? This was interesting. You can read, obviously, but you're actually putting your face in the book. Why? What does that mean?

BAGGS: I like the smell and the texture of that particular paper. That book has really rough paper.

GUPTA: Amanda says this is her natural way of thinking, in patterns and in colors, thinking with language and written words as we do is not natural for her. Therefore, she struggles with it. If you wanted to talk to me, could you do that?

BAGGS: I could make speech sounds. At this point, I could not make them mean anything I was thinking.

GUPTA: Does that frustrate you?

BAGGS: Not really. I type really very fast.

GUPTA: Yes, you do.

Yes, she types very fast. When she's feeling good and not distracted, Amanda types about 120 words a minute. But her ability fluctuates. Some days she can only type with one finger at a type. And occasionally, she can not type at all. On rare days, Amanda can become catatonic. Distractions, interferences, sensory overloads all present huge obstacles for Amanda.

So she is most secure and most comfortable here at home with her dog Billy Jean and with all of her computer equipment as well. But when she leaves here, she's assaulted by too much stimulation.

I went with her to see her dentist. She uses a wheelchair, not because she can't walk -- she can -- but she says the very act of balancing herself proves too distracting.

And you'll notice she's focused on her keyboard. In the dentist chair, the buzz and flicker of the fluorescent lights are overwhelming for her. They can trigger migraines. So Amanda soothes herself. She fiddles with her blocks. They are familiar and calming.

When Amanda hit herself, I was startled, but not surprised. It is a familiar autistic behavior. She must be so frustrated. Such a bright woman, so trapped. And yet I wondered, how is it is that Amanda has been able to reveal so much about herself? And how many more people are there just like her?

(END VIDEOTAPE)

GUPTA: It's really remarkable to meet her. Amanda is technically a low-functioning autistic. That's her diagnosis. The hallmarks are obsessive-compulsive behaviors, that erratic hand flapping that you saw, occasional head banging, even regression. They will lose some of their abilities as they get older. In fact, that was the case with Amanda as well. When she was younger, she actually talked.

(BEGIN VIDEOTAPE)

GUPTA (voice-over): It's a bit disconcerting talking to Amanda. Typical of people with autism, there is no eye contact.

BAGGS: There is problems I don't know on my meds.

GUPTA: Until she responds with her keyboard and voice synthesizer, it's hard to know if what I'm saying actually registers.

If you didn't have this, how would I communicate with you? How would I understand what you're trying to tell me? How would you guide me or at least help me understand you?

BAGGS: I tend to kind of bludgeon people over the head with that kind of communication. Not sure.

GUPTA: Growing up, Amanda attended regular public schools. She could read at an early age. It's called hyperlexia, and it's common for people with autism. She says she learned spelling by reading. She learned to type with a teaching software. Then in her teens, she slowly lost her ability to talk. Would you say that people would be surprised to find out how well you can communicate being a person with autism?

BAGGS: Generally, if they see me first before they see me talk, they are surprised, and sometimes disbelieving. And then sometimes if they first see me, right, they think that I'm not autistic.

ERIC HOLLANDER, DR., AUTISM CENTER OF EXCELLENCE: What's extraordinary is that some individuals that you think are mentally retarded and have no language, once they're able to communicate through a keyboard, they have high-level processing and thinking about the world. And they're able to communicate in an expressive fashion.

GUPTA: Remember, that's how we first found Amanda, via her computer on YouTube. In fact, the Internet has allowed her to leave her secure and orderly, little apartment to meet others with autism. For example, she likes to go to an online community called "Second Life," where she's created an animated alter ego, who looks and acts like her. Even here in her virtual world, she's typing and rocking back and forth.

HOLLANDER: The big advantage of the Internet for people with autism is it does filter out all of the facial expressions and the body language. So people don't have to spend time trying to disentangle or understand the non-verbal forms of communication.

GUPTA: What are we missing here? Why has autism been this, something that people have not really been able to get their arms around in terms of being able to communicate, be able to understand it fully?

BAGGS: There's a communication gap that goes two ways. It's not a one way street. And so part of the problem is that the people are not thinking. If they don't understand us, it's because we are broken. And if we don't understand them, it is because we're broken.

GUPTA: As for communicating with others who have autism, Amanda said it's not about words. I asked her about an autistic woman she wanted to meet. Why didn't you just look at her and make a motion, like hello or hi or wave the hand or something to acknowledge her at the time?

BAGGS: That would be a bit invasive, wouldn't it?

GUPTA: Well, it happens all the time. I mean, I think a lot of people would understand that sort of gesture. Do you think that she would have been offended by it or that it would have been too invasive to her?

BAGGS: When I'm around other autistic people where the meaning is known already, why bother with forcing an arm to do all that when you can already make the meaning clear? It's redundant.

Why would I spend not only the physical energy on doing the motion, but the cognitive energy working out which particular motion is the one you want out of me right then? It's like running calculus in your head to say hi. And it's not usually work it in the long run.

GUPTA: In other words, meeting our expectations is not important for her. It can actually overwhelm her.

What is the message then, for the parents, for the people who are providers? I mean, try harder to communicate?

BAGGS: Listen to other autistic people. In fact, expose autistic children to a wide variety of autistic adults. It may be the autistic adults who do have neither typing or speech, who are far more equipped to be able to communicate with other autistic people.

(END VIDEOTAPE)

GUPTA: You know, as a doctor, this was a remarkable experience just getting to sit down with Amanda. You can read all about my thoughts about the interview and tell me yours as well by going to my blog, cnn.com/health. Also on that health page, you're going to find out how computers are helping adults with autism and a link to Amanda's video that first intrigued us so much. First, stay where you are, though.