Neuroimaging study identifies new biomarker for autism spectrum disorder in boys.

Autism spectrum disorder (ASD) is marked by social disability and is associated with dysfunction in brain circuits supporting social-cue perception. The degree to which neural functioning reflects individual-level behavioural phenotype is unclear, slowing the search for functional neuroimaging biomarkers of ASD.  Now, researchers led by George Washington University develops a new method to map and track the function of brain circuitry affected by ASD in boys using neuroimaging. The team state that their technique will provide clinicians and therapists with a physical measure of the progress patients are making with behavioural and drug treatments, a tool that has been elusive in autism treatment until this point.  The study is in the journal JAMA Psychiatry.

Previous studies show that ASD are characterized by impairments in social communication and restrictive, repetitive behaviours. While behavioural symptoms are well-documented, investigations into the neurobiological underpinnings of ASD have not resulted in firm biomarkers.  Variability in data across neuroimaging studies has contributed to the difficulty in characterizing the specific brain-imaging markers of individuals with ASD. These inconsistencies may also arise from the heterogeneity of ASD, and wider age-range of participants included in MRI studies.  The current study investigates the use of biomarkers, measurable indicators of a biological condition, to measure the function of the social perception circuit of the brain, in boys with ASD.

The current study analyzes a series of 164 images from each of the 114 study participants and discovered the brain scans of the social perception circuits only indicated ASD in boys.  Results show that the brain scan data can be an effective indicator for function of the social perception circuits in younger children and older patients alike.  Data findings have the potential to improve treatment for ASD by measuring changes in the social perception brain circuit in response to different interventions.

The lab state that the research is particularly relevant for ASD patients who are difficult to diagnose and treat by providing a more definitive diagnosis, and in developing a treatment program when it is not clear which treatments will be the most effective.  They go on to explain that the behavioural symptoms of ASD are so complex and varied it is difficult to determine whether a new treatment is effective, especially within a realistic time frame; brain function markers may provide the specific and objective measures required to bridge this gap.

The team surmise that in addition to helping to identify the most effective ASD treatment for an individual, this research provides evidence that brain imaging is an important intervention tool.  For the future, the researchers state they are studying a larger pool of people with autism to see if the scan can successfully distinguish ASD from other disorders and track treatment progress.  They go on to conclude that while this method currently only works for boys with autism, they are also leading a large-scale, nationwide study of girls with autism to identify equivalent techniques which will work for them.

Source: The George Washington University