Feb. 15, 2008 (Boston) -- Children generally love to play with computers, but many children with autism prefer interacting with a computer to conversing with a person. Many scientists have been working on ways to take advantage of that to help autistic kids learn.
A virtual talking head, or "embodied conversational agent," nicknamed Baldi by its creators, is one of the latest technologies being used to teach language skills to autistic kids. Dominic Massaro, PhD, a language researcher at the University of California, Santa Cruz, demonstrated Baldi at this week's annual meeting of the American Association for the Advancement of Science.
If you've seen virtual characters in video games, you may notice that as realistically rendered as they may be, their mouths typically don't move in a natural way when speaking. The difference with Baldi is the extent to which Massaro has realistically modeled the virtual mouth movements. Baldi's whole face -- including the tongue, jaw, and lips -- moves the way a real person's does when making different spoken sounds. This is important for learning, Massaro says, because language is learned not only by ear but also by sight. "People use cues from both the face and the voice," he says.
In experiments with Baldi, Massaro showed that children recognized many more words in sentences when watching the talking head than by listening only.
To accurately model mouth movements for the computer graphics, Massaro used ultrasound images of people's tongues during speaking. Measurements are taken with sensors placed all over the face and a special sensing plate placed inside the mouth. The inside of Baldi's mouth can be revealed to see how he's making a certain sound, like an "r" sound or "th" sound.
Learning with Baldi occurs in the context of a software program with features that are friendly to autistic kids.
The program uses a style called "errorless" learning. "The child is not told he's wrong if he makes a mistake," Massaro says. Instead, the program will suggest how to get to the right answer in positive terms. For example, the program prompts, "Click on elephant." If the child clicks on a picture of a giraffe instead, it will say, "You clicked on giraffe. A giraffe is an animal with a long neck. An elephant is an animal with a long trunk. Can you click on elephant?"
For autistic children who become easily frustrated, this can be a big plus. The virtual tutor is also available 24/7 and has endless patience. Part of what makes him appealing to autistic kids is that he never gets frustrated with them. He's predictable.
"Children with autism are very uncomfortable with unpredictability," says Justine Cassell, PhD, a researcher at Northwestern University in Evanston, Ill., who works on a different virtual reality program that teaches social skills to autistic kids.
Some parents feel funny about kids learning with a virtual person, but Cassell says there's no harm in it. "I think we should be comfortable with virtual reality," she says.
Although virtual reality has been studied with autistic children extensively, most programs haven't left the laboratory. Baldi, however, is available to the public. Schools and families can purchase the software to use at home or in the classroom from Massaro's private company, Animated Speech Corp.
Massaro says he tries to keep up with users as part of ongoing evaluation of the technology, and he stresses that it is experimental.
James Glass, PhD, a language researcher at MIT, says that this kind of technology is perfected by dissemination as well as by controlled study. "You need to get it out there to see how people will really use it," he says.
Massaro is also testing Baldi as a tool for teaching people with other kinds of language challenges, such as impaired hearing, and for teaching vocabulary to children with normal abilities. Another use is foreign language learning. The software can be programmed to speak any language.