NEW YORK (Reuters Health) - Children with autism often have difficulty understanding spoken language, and new research released Monday may help explain why.

Patterns of brain activity in autistic children as they listen to sounds reveal that they indeed hear and listen to language, but fail to pay attention to the sounds the words make.

In contrast, brain scans showed that children with autism appeared to both hear and pay attention to musical tones of a similar complexity to language.

These results contradict previous theories that suggested that children with autism do not learn language because they are unable to take in and process complex sounds.

All of the children included in the study were between the ages of 6 and 12 were considered to be high functioning, meaning they had an IQ above 70 and could speak some words.

But without attention to the sounds words make, learning to fully speak and understand language is impossible, study author Dr. Rita Ceponiene of the University of California at San Diego told Reuters Health.

"Attending to something is a necessary prerequisite for learning," she said.

Ceponiene said that the findings may also one day help researchers identify infants with autism earlier, and children who are diagnosed earlier with the condition often fare better.

However, she cautioned that much more work is needed before researchers can provide parents with new tools to help their children with autism learn language.

"This is a step. It's quite an informative step. But, unfortunately, it's still far from giving something that's applicable on the everyday basis to these parents," Ceponiene said.

During the study, Ceponiene and her colleagues measured brain activity linked to hearing and processing sound in nine children with autism and 10 children without the condition.

The children listened to a series of simple and complex tones and vowels. At one point, the investigators changed the pitch of the tone or vowel played for the children, and recorded how their brains responded to the deviating sounds.

The results appear in the early online edition of the Proceedings of the National Academy of Sciences.

The investigators discovered that autistic children were able to hear and process the sound of both vowels and musical tones equally well.

However, while autistic children appeared to attend to changes in the pitch of simple and complex musical tones, they did not heed any changes in the sound of vowels.

"They did not move their attention to changes in speech sounds," Ceponiene noted.

A lack of attention to the sounds of language may be one reason why children with autism have trouble learning language, she noted.

As an alternative, Ceponiene noted that children with autism may have been able to pay attention to language when younger, but lacked the ability to extract meaning from what they heard. This inability may have led them to eventually stop paying attention to what they heard.

If language never made sense to autistic children, "with time, they might learn to ignore it," the researcher explained.

The current study findings also appear to corroborate previous research that found that people with autism can outperform their peers in certain tasks related to musical abilities.

To parents of autistic children, Ceponiene offered one bit of advice: Keep talking.

Even if children are unable to understand what the words mean, perhaps a little more exposure and practice will cause something to click in their minds, she said.

"So maybe they should not give up speaking to them," Ceponiene noted.

Continuing to expose autistic children to language may help "provide more opportunities to exercise the skill that is weak in them," she added.

SOURCE: Proceedings of the National Academy of Sciences 2003;10.1073/pnas.0835631100.

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