The MIND Institute Now Recognizes a Distinct Autism-Related Type of Anxiety
The amygdala is a small, almond-shaped structure found deep within the temporal lobe of the brain. It plays a role in processing emotion and fear and has been associated to both autism and anxiety. Now, a long-term study involving hundreds of brain scans has discovered that changes in the amygdala are associated with the development of anxiety in children with autism spectrum disorder (ASD). This research was conducted by the UC Davis MIND Institute and provides evidence of distinct types of anxiety specific to autism. Anxiety is common in autism. Previous research by the institute has demonstrated that the rate of anxiety is 69% in children with autism and 8% in neurotypical children. The current study’s design used magnetic resonance imaging (MRI) to scan the brains of 71 children with ASD and 55 children without the disorder. Participants were between the ages of 2 and 12. Each child was scanned up to four times during the study. Additionally, clinical psychologists with an expertise in autism interviewed the parents of all participants about their child’s behaviors. The researchers included questions about traditional anxiety, as defined by the DSM-5, and also used the Anxiety Disorders Interview Schedule (ADIS) as well as the Autism Spectrum Addendum (ASA), which were developed to identify autism-specific anxieties. The results demonstrated that approximately 50% of the children with autism had traditional anxiety or autism-distinct anxiety, or both. Children on the spectrum with traditional anxiety had significantly larger amygdala volumes compared to neurotypical children. The opposite was true for children with ASD with autism-distinct anxieties. They had notably smaller amygdala volumes. David Amaral, co-senior author on the paper, commented on the study’s findings and stated, “Given that clear brain alterations are associated with autism-distinct anxiety tends to validate the concept of the existence of this type of anxiety in autism.”