Table 2.
Volumetric asymmetry indices (AI) by region in ADHD (DEHB) and healthy control groups.
| Brain region | AI mean ± SD (ADHD, n = 40) | AI mean ± SD (controls, n = 30) | t(66) | p | Cohen’s d | Direction of asymmetry (HC vs. ADHD) |
|---|---|---|---|---|---|---|
| Frontal lobe volume | +0.010 ± 0.020 | +0.031 ± 0.021 | 3.10 | 0.003 | 0.75 | Rightward ↓ in ADHD |
| Parietal lobe volume | +0.006 ± 0.017 | +0.008 ± 0.018 | 0.42 | 0.67 | 0.10 | ns |
| Temporal lobe volume | +0.004 ± 0.015 | +0.006 ± 0.016 | 0.47 | 0.64 | 0.12 | ns |
| Occipital lobe volume | 0.000 ± 0.012 | 0.000 ± 0.011 | 0.01 | 0.99 | 0.00 | Symmetric (control check) |
| Cerebellar hemispheres | −0.003 ± 0.019 | +0.012 ± 0.018 | 2.45 | 0.017 | 0.60 | Leftward shift in ADHD |
| Caudate nucleus | +0.002 ± 0.014 | +0.018 ± 0.016 | 2.90 | 0.005 | 0.70 | Rightward ↓ in ADHD |
| Putamen | +0.004 ± 0.015 | +0.020 ± 0.018 | 2.60 | 0.011 | 0.63 | Rightward ↓ in ADHD |
| Amygdala | −0.007 ± 0.013 | +0.006 ± 0.014 | 2.20 | 0.031 | 0.52 | Reversed (Left > Right) in ADHD |
| Thalamus | +0.001 ± 0.012 | +0.008 ± 0.013 | 1.83 | 0.07 | 0.45 | Trend (Rightward ↓) |
| Hippocampus | +0.004 ± 0.015 | +0.007 ± 0.015 | 0.77 | 0.44 | 0.19 | ns |
AI, Asymmetry Index; HAI, Hemispheric Asymmetry Index; ACC, Anterior Cingulate Cortex; IFG, Inferior Frontal Gyrus; MOXO-d-CPT, MOXO-digital Continuous Performance Test; SD, Standard Deviation; ns, non-significant.