Autism and ADHD: Differential Functioning on a Computerized Performance Test (MOXO-CPT)

Objective: ADHD & Autism Spectrum Disorder (ASD) have recently been discussed as sharing etiology and symptomatolgy, to such an extent that 60% of children with ASD show symptoms of ADHD, and some 30% of ADHD children have difficulties in social communication. The overlap or similarity of these two neurodevelopment disorders requires further studies, to understand their common denominator.

Method: We examined the performance of 25 ASD children (no ADHD) (>6years) and 25 ADHD (no ASD) children matched for age, gender and socioeconomic status on a computerized performance test (MOXO-CPT which incorporates visual and auditory stimuli serving as environmental distracters), commonly used as one of the tools in the clinical diagnosis of ADHD.

Results: We found that children with ASD performed better (borderline significance) on 3\4 test items (Attention, Timing, Hyperactivity), while Impulsivity was the same in both groups. Both groups were affected by visual and auditory distracters built-in the MOXO paradigm, but ASD children were significantly less distracted, and showed better performance consistency over time than the ADHD group.

Conclusion: On our computerized test battery MOXO, children with ASD showed better performance than ADHD children on most test items, challenging previous studies on this issue. Computerized Performance Test might provide a "protected" environment for ASD children that does not unravel their attention difficulties under naturalistic conditions.