Reduced recruitment of inhibitory control regions in very young children with ADHD during a modified Kiddie Continuous Performance Task: a fMRI study.

Attention-Deficit/Hyperactivity Disorder (ADHD) symptom profiles are known to undergo changes throughout development, rendering the neurobiological assessment of ADHD challenging across different developmental stages. Particularly in young children (ages 4 to 7 years), measuring inhibitory control network activity in the brain has been a formidable task due to the lack of child-friendly functional Magnetic Resonance Imaging (fMRI) paradigms. This study aims to address these difficulties by focusing on measuring inhibitory control in very young children within the MRI environment. A total of 56 children diagnosed with ADHD and 78 typically developing (TD) 4-7-year-old children were examined using a modified version of the Kiddie-Continuous Performance Test (K-CPT) during BOLD fMRI to assess inhibitory control. We concurrently evaluated their performance on the established and standardized K-CPT outside the MRI scanner. Our findings suggest that the modified K-CPT effectively elicited robust and expected brain activity related to inhibitory control in both groups. Comparisons between the two groups revealed subtle differences in brain activity, primarily observed in regions associated with inhibitory control, such as the inferior frontal gyrus, anterior insula, dorsal striatum, medial pre-supplementary motor area (pre-SMA), and cingulate cortex. Notably, increased activity in the right anterior insula was associated with improved response time (RT) and reduced RT variability on the K-CPT administered outside the MRI environment, although this did not survive statistical correction for multiple comparisons. In conclusion, our study successfully overcame the challenges of measuring inhibitory control in very young children within the MRI environment by utilizing a modified K-CPT during BOLD fMRI. These findings shed light on the neurobiological correlates of inhibitory control in ADHD and TD children, provide valuable insights for understanding ADHD across development, and potentially inform ADHD diagnosis and intervention strategies. The research also highlights remaining challenges with task fMRI in very young clinical samples.

Exploring Differences in Physical Health in Young Children With and Without ADHD.

OBJECTIVE: To assess differences in child physical health outcomes and metrices associated with obesity in a sample of predominantly Hispanic/Latinx young children with and without attention-deficit/hyperactivity disorder (ADHD). METHODS: Participants included 127 children diagnosed with ADHD and 96 typically developing (TD) children between 4 and 7 years of age. Objective measures of children's body composition, fitness, and physical activity were conducted. Parents of children completed food recalls to assess their child's dietary intake, diet quality was calculated based on the Healthy Eating Index-2015, and parents completed a survey about their family's health habits. RESULTS: Logistic regression revealed that those with ADHD were more likely to be classified as having an overweight or obese (Ov/O) body mass index (BMI). Linear regression analyses indicated that children with ADHD performed worse on a fitness test and consumed more calories relative to TD children. Moderation analyses indicated that sex differences in steps were prominent in our TD sample, but not among those with ADHD. CONCLUSIONS: Young children with ADHD are at greater risk for having an Ov/O BMI, being less fit, and eating a greater intake of calories compared to TD children.