American and British scientists conducted a cross-sectional study and concluded that assessing motor imitation using an experimental video game improves the accuracy of differential diagnosis of autism spectrum disorders (ASD). The report was published in The British Journal of Psychiatry.
Currently, there are no reliable and specific biomarkers in clinical practice to distinguish autism spectrum disorders (ASD) from another common and frequently associated condition, attention deficit hyperactivity disorder (ADHD). This complicates diagnosis and timely access to treatment, negatively impacting patients' quality of life.
Romila Santra of the Kennedy-Krieger Institute and colleagues from the UK and US recruited 183 children aged 7–13 years to participate in the study. Thirty-five of them had ADHD without ASD, 63 had ASD with comorbid ADHD, 21 had ASD without ADHD, and the remaining 65 were neurotypical (without neuropsychiatric features). The diagnoses met DSM-5 criteria. All participants had preserved intelligence (IQ 70 or higher). The children were assessed using the standardized ADOS-2 test, the SRS-2, Conners-3, and Conners-4 parent questionnaires, and the PANESS behavioral assessment with and without the CAMI. CAMI (Computerized Assessment of Motor Imitation) is an experimental method that involves asking children to imitate dance-like movements with their entire body following an avatar on a screen during two-minute sessions. During this time, they are filmed in two projections with video cameras, and the average accuracy of their imitation is calculated from 0 to 1.
It was found that neurotypical children and children with ADHD had comparable imitation accuracy on the CAMI, while it was significantly reduced in children with ASD, regardless of the presence of comorbid ADHD (p < 0.0001; R2 = 0.28). ROC curve and support vector machine analysis showed that the method significantly helps distinguish children with ASD from both neurotypical children (80 percent true positive rate) and children with ADHD (70 percent true positive rate). Among participants with ASD, low CAMI scores were associated with more pronounced autistic traits, specifically the level of social affect and restricted and repetitive behavior patterns on the ADOS-2, but not with ADHD features or motor skills. Thus, computerized assessment of motor imitation can serve as a relatively simple and objective additional method for differential diagnosis of ASD, including when differentiating it from ADHD, the authors conclude. Previously, diagnostic approaches for ASD included eye tracking using a smartphone app, blood testing for the adipokine FABP4, and processing functional brain connectivity maps using machine learning algorithms. More detailed information about ASD can be found in the article "Children of the Rain."
