Compared to those with comorbid anxiety, only children with ADHD without comorbid anxiety showed a normative reduction in high-frequency heart rate variability during a cognitive challenge.
Cross-Sectional (n=46)
Does a sustained attention task alter high-frequency heart rate variability in children with ADHD with and without comorbid anxiety?
Children with ADHD exhibit abnormal autonomic nervous system responses to cognitive stress, characterized by prolonged vagal withdrawal during recovery and differential reactivity based on comorbid anxiety.
Autonomic nervous system (ANS) dysregulation, characterized by reduced vagally mediated Heart Rate Variability (HRV), has been associated with Attention-Deficit/ Hyperactivity Disorder (ADHD). This study investigated the dynamic vagal modulation of cardiac output in response to shifts in environmental demands in children and adolescents with ADHD, with and without a comorbid anxiety disorder. High-frequency HRV (HF-HRV) measures were obtained from 46 children and adolescents ranging from 6 to 17 (M = 9.38; SD = 2.31) years old, during three successive experimental conditions: a baseline recording followed by a sustained attention task, and a post-task recovery period. Findings support the reliability of the d2 Test, a cancelation test of attention and concentration, to induce parasympathetic withdrawal and extend prior work on "vagal flexibility". Further, these findings suggest a pattern of group differences in ANS functioning in children with ADHD, with and without a comorbid anxiety disorder. Only the ADHD without comorbid anxiety group showed a normative autonomic response to the cognitive challenge (reduced HF-HRV). The participants did not display an adaptive process of restoration following the cognitive challenge; the HRV suppression was prolonged during post-task recovery period, suggesting that ANS responded as if the cognitive stressor was still present. The current paper covers and discusses theoretical implications for the abnormalities in neurophysiological functioning and the different physiological responses in the two ADHD subtypes.
Robe et al. (Fri,) conducted a cross-sectional in Attention-Deficit/Hyperactivity Disorder (ADHD) with and without comorbid anxiety disorder (n=46). ADHD without comorbid anxiety vs. ADHD with comorbid anxiety was evaluated on High-frequency heart rate variability (HF-HRV) during baseline, sustained attention task, and post-task recovery. Compared to those with comorbid anxiety, only children with ADHD without comorbid anxiety showed a normative reduction in high-frequency heart rate variability during a cognitive challenge.