Autism study’s practical potential

by Hannah Beausang

Researchers at San Diego State have made groundbreaking strides in diagnosing autism.

The research, fronted by SDSU and University of California San Diego Joint Doctoral student Aarti Nari  and SDSU psychology professor Ralph-Axel Müller, could help target autism at early stages of development.

The study incorporated functional and anatomical magnetic resonance imaging methods along with diffusion tensor imaging to investigate links between the cerebral cortex and thalamus. With the use of the different types of imaging, the team examined the functionality and intactness of connections in the brains of patients with and without autism.

Sensory information—including vital elements such as vision, attention hearing and motor control—that is processed by the brain enters through the thalamus and is directed to other regions of the brain. Nair said the thalamus has not been examined in-depth during other autism studies because it is housed deep within the brain and is difficult to observe.

“It has a pretty crucial role in the brain,” Nair said. “This is a brain region that has surprisingly not been studied much in autism.”

Müller, the senior investigator of the study, who has been involved in autism research for more than 20 years, enunciated the importance of the inner brain connections.

“It’s been known for a long time that the cerebral cortex is like a map,” Müller said. “When you look at prenatal brain development, these connections between the thalamus and cerebral cortex are actually heavily involved in telling the cerebral cortex how to specialize.”

The study revealed that connections between the thalamus and the cerebral cortex of children with autism were affected. The cerebral cortex, the outer layer of the brain, is crucial in high-level cognitive functions as well as sensory functions, such as motor control.

The study examined 50 children ranging from ages 9 to 17 who were recruited from local clinical neuropsychologist Dr. Alan Lincoln, from the community and through advertisements at SDSU and UCSD

Visual evidence from the study showed reduced connections that tied in with autism traits and symptoms in the observed children.

Nair said autism research is moving toward the investigation of sensory motor skills, which were examined in this study.

“If you look at the trend with autism right now, both the changes in the diagnosis and the Diagnostic and Statistics Manual as well as the measures used to diagnose autism, there’s a bigger focus on the sensory motor skills now than there has been in the past … the sensory motor skills are some of the initial symptoms that develop,” Nair said.

Nair said the findings from the research could potentially be utilized to devise an intervention or a type of neuro-feedback training to specifically target the thalamus, reducing future symptoms in autistic children.

The team is now examining more specific regions of the brain to fine-tune the study and apply the findings to a more encompassing age sample. They also plan to observe metabolite levels in the thalamus in order to measure the neurotransmitters and compare the results from autistic patients and normally developing patients.

“If we can detect this risk very early, then providing these kids with interventions that target sensory and movement abilities could possibly be very beneficial,” Müller said. “It could help them to not develop autism with the severity we would normally see.”

The research was funded with a grant from the National Institutes of Health as well as the Autism Speaks Dennis Weatherstone Predoctoral Fellowship and was published in the June edition of Oxford Journals BRAIN Journal of Neurology.