Researchers are currently learning more about regressive autistic spectrum disorder (RASD), a form of autism in which children slowly lose much of their developing language and social skills.

“Often children with regression aren’t being seen by professionals at the time of the loss of skills. The parents are aware of a problem, but not sure what it is so they

don’t seek medical or psychological help until the symptoms persist for over a year,” said Gerry A. Stefanatos, D.Phil., an associate professor in the Department of Communication Sciences and Disorders in Temple University’s College of Health Professions.

Stefanatos writes about RASD and the growing research into this disorder in the December issue of Neuropsychology Review. He estimates that about 25 to 30 percent of children eventually diagnosed with autism have the disorder.

Children with RASD seem to develop normally until 18 to 24 months. At that point, they have acquired a small vocabulary and social behaviors, but over the course of weeks or months lose their speech and no longer use words they had learned previously. They have problems comprehending and lose the ability to follow commands.

“One of the more obvious cues for parents is if the child no longer responds to his or her own name,” said Stefanatos. “Oftentimes this is accompanied by deterioration in behavior. They child can become irritable, prone to tantrums.”

Information about regression is commonly obtained retrospectively months to years after symptoms begin. Due to the subtle signs of regression, it’s difficult for many parents to identify a point at which their child’s behaviors began.

“If you have suspicions, go and see a pediatrician and explain what you’re seeing in your child,” Stefanatos said. “If there is in fact a regression, it helps to have another set of eyes to confirm suspicions. You may also want to seek out a specialist in autism to assist with diagnoses. Because you are with your child every day, it can be difficult to appreciate subtle changes over time.”

When Stefanatos works with parents, he frequently asks them to provide video of the child at various points in development (birthdays, holidays) to determine the history of the potential disorder. The videos can show the child engaged with people and yet a year later, show that same child with serious withdrawal.

Among the many potential causes of regression, Stefanatos said healthcare providers or autism specialists who suspect RASD should look for evidence of an electroencephalographic (EEG) abnormality, which might suggest an epileptic or seizure disorder. An EEG measures electrical activity produced by the brain and is recorded from electrodes placed on the scalp.

Seizure-related brain activity can act like “electrical noise” and interfere with the function of areas of the brain responsible for different areas of development. This noise can potentially be disruptive to the wiring of connections between brain cells developing at that stage. In these cases, medications may reduce disruptive electrical discharges so they don’t have a negative influence on neurological development.

“When it’s treated, either behaviorally or medically, there can be a significant improvement in behavior and development,” said Stefanatos. “This is one reason why it’s important to identify RASD as early as possible.”

More research is required to explore the similarities and differences between RASD and ASD. In the meantime, it’s important for parents and healthcare providers to pay attention to any lost developmental milestones.

“Be very attentive to that aspect of child’s history and act accordingly; take it very seriously,” said Stefanatos. “It (regression) can be a red light that something is amiss with a child’s development and the issue needs to be looked at in more detail.”

—Written by Anna Nguyen