NIH Grant to Aid Autism Language Investigation

A UT Dallas neuroscientist has earned a $1.6 million, five-year grant from the National Institutes of Health to investigate how autistic children process language and why they experience communication difficulties.

The National Institute on Deafness and Other Communication Disorders awarded the grant to Dr. Michael Kilgard, associate professor in the School of Behavioral and Brain Sciences. The funds will enable his lab to evaluate therapies aimed at counteracting the speech- and sound-related deficits that often limit the ability of autistic people to learn and live independently.

“We hope this round of research helps us learn more about what happens in autism,” Kilgard said. “Ultimately, we hope to provide some benefits to relieve the difficult challenges faced by people with autism, as well as their families and others who care for them.”

Recent surveys report that about one in 150 people in the United States is affected by autism. The disorder is usually characterized by social impairments, language deficits and repetitive behaviors.

Research has shown that autistic individuals are severely impaired in their ability to process subtle communication cues, which also leads to obstacles in routine social interaction.

But the neural mechanisms responsible for the impairments are not well understood.

Brain scans have confirmed serious deficits in speech sound processing in the brains of children and adults with autism.

“Unfortunately our current imaging methods don’t allow us to record from individual brain cells in patients,” Kilgard said. “We can only see what broad regions of the brain are doing. With speech, individual cells make a big difference in how sounds are processed.”

To develop more effective interventions to improve speech and language development, researchers need a better way to detect the minute differences in how cells process sounds and speech. Kilgard has created a rat model of autism to help in that effort. He and his team are using the lab rats to identify a potential explanation for why autistic people can’t discriminate effectively between certain sounds.

Kilgard created rats that bear the symptoms of autism by injecting them with a large dose of an anticonvulsant drug used to treat epilepsy. The medication, known as valproic acid or VPA, is linked to the development of autism in human children, and exposure to VPA during pregnancy causes symptoms of autism in the lab rats, he said.

Animals process speech sounds in much the same way humans do, so electrodes placed within the brains of these rats can tell researchers how different areas respond to speech. Kilgard’s team will test promising therapies on the rats to test their effectiveness.

“People still have a lot of questions about what causes autism and how to treat it, so there are hundreds of available therapies to choose from,” he said. “Most are ineffective and a potential waste of time and resources. But there are at least a couple of therapies that show a great deal of promise, and we want to look at those more closely.”

Recent research indicates intensive behavioral training can substantially improve language proficiency in children with language deficits, Kilgard said. Other work has shown that intense play-based therapy can also be very effective for young children with autism.

Autistic individuals tend to be introverted and do not seek social interaction. But researchers have found, mostly through anecdotal and observational studies that exposing them to more different people, sounds and experiences decrease their symptoms and aids their communication.

Despite recent progress, many basic questions remain regarding the neurological basis of speech comprehension impairments in autism. By better understanding how individual neurons process speech sounds, physicians and therapists may be able to design new strategies for improving communication in individuals with autism.

Kilgard and his team will conduct experiments with rats to determine how the two most common autism therapies aid the brain. One group of rats will be trained to distinguish speech sounds using methods that are similar to speech therapy for autism. Another group will receive attention akin to play therapy in what Dr. Kilgard calls “rat Disneyland,” where rats have many opportunities for social interaction, exercise and play.

The UT Dallas researchers are recording the brain activity of the rats involved in these therapies and analyzing whether the treatments spur their brains to exhibit improved speech sound processing. If the therapies’ effectiveness is confirmed in rats, researchers can use the approaches to develop new and better treatments for addressing autism.

In later stages of the study, Kilgard plans to investigate whether autism symptoms caused by other drugs or gene mutations can also be treated using behavioral and play-based therapies.

Kilgard is excited to have such a vibrant community of clinical experts on autism to interact with. Together UT Dallas researchers are offering new hope to families faced with the challenges of autism, he said.

“Mike Kilgard has emerged as one of the world’s experts on how the brain processes and is altered by auditory information,” said Dr. Bert Moore, dean of the School of Behavioral and Brain Sciences at UT Dallas. “This grant has the promise to extend this work to one of the fundamental characteristics of autism, the apparent deficit of registering and responding to social information. Dr. Kilgard’s research is an important component of extensive collaborations between UT Dallas, UT Southwestern Medical Center and Children’s Medical Center to address causes and interventions for autism.”