Indices of Heart Rate Variability and Performance During a Response-Conflict Task Are Differently Associated With ADHD and Autism.

This study looked at how the nervous system responds to challenging tasks in children with ADHD, autism, or both conditions. Children with ADHD showed lower heart rate changes during tasks, which was linked to slower performance. Children with autism had different brain activity patterns during information processing. Both groups performed more slowly and less accurately than neurotypical children.

Children with both ADHD and autism may face extra challenges because they have both types of nervous system differences affecting their performance.

This study examined autonomic nervous system functioning and cognitive performance in 78 children and adolescents (ages 7-15) with ADHD, autism, comorbid ADHD+autism, or neurotypical development. Researchers measured heart rate variability (HRV) and brain activity during a response-conflict task. Both ADHD and autism groups showed slower and less accurate performance, but had different underlying neurophysiological patterns. In ADHD, reduced HRV in response to task cues mediated slower performance, suggesting autonomic hypo-arousal and difficulties mobilizing cognitive resources.

Autism showed distinct electrophysiological differences in information processing. Children with both conditions (ADHD+autism) may experience compounded cognitive difficulties due to these different but co-occurring neurophysiological differences affecting performance.

Findings suggest different physiological mechanisms underlie similar cognitive difficulties in ADHD versus autism. This supports tailored intervention approaches. For ADHD, interventions targeting autonomic regulation may be beneficial. For autism, approaches addressing information processing differences may be more appropriate. Comorbid cases may require combined strategies.

Sample size not specified in abstract. Study design unclear. Cross-sectional nature limits causal inferences. Age range is broad (7-15 years) which may introduce developmental confounds. No information provided about medication status or severity levels of participants.

We investigated autonomic arousal, attention and response conflict, in ADHD and autism. Heart rate variability (HRV), and behavioral/electrophysiological indices of performance, were recorded during a task with low and high levels of response conflict in 78 children/adolescents (7-15 years old) with ADHD, autism, comorbid ADHD+autism, or neurotypical. ANOVA models were used to investigate effects of ADHD and autism, while a mediation model was tested to clarify the relationship between ADHD and slower performance. Slower and less accurate performance characterized ADHD and autism; however, atypical electrophysiological indices differently characterized these conditions.

The relationship between ADHD and slower task performance was mediated by reduced HRV in response to the cue stimulus. Autonomic hypo-arousal and difficulties in mobilizing energetic resources in response to sensory information (associated with ADHD), and atypical electrophysiological indices of information processing (associated with autism), might negatively affect cognitive performance in those with ADHD+autism.