Attention Deficit Hyperactivity Disorder Related Pattern In Children Based On Structural And Functional Magnetic Resonance Imaging

Attention deficit hyperactivity disorder（ADHD）is one of the most prevalent childhood-onset neurodevelopmental disorders with a high prevalence.Inattention is a key characterization of ADHD and rarely vanishes relative to the significant relief of hyperactive/impulsive symptoms over time.However,the underlying neural mechanisms for the inattention symptom remain elusive for children with ADHD.This study aimed to identify the gray matter（GM）network associated with attention in children with ADHD（i.e.,ADHD related pattern）,and then investigated functional abnormalities of the ADHD related pattern.Specifically,two studies were carried out and the main contents of them are as follows:In the first study,we used the scaled subprofile model of principal component analysis（SSM-PCA）,a multivariate method,to identify the ADHD related pattern.The structural MRI of 209 children（age:10.81±2.11）with ADHD and 209 typically developing controls（TDC）（age:10.84±1.90）were used for anatomical computation.Then,SSM-PCA was applied to the GM volumes of all the subjects to capture the ADHD related pattern.The relationship between the expression of ADHD-related pattern and inattention symptom was further investigated.Finally,the influence of sample size on the analysis of the current study was explored.Our results demonstrated that the ADHD-related pattern mainly included putamen,pallium,caudate,thalamus,right accumbens,superior/middle/inferior frontal cortex,superior occipital cortex,superior parietal cortex,and left middle occipital cortex.In addition,the expression of the ADHD-related pattern was related to inattention scores measured by Conners’Parent Rating Scale long version（CPRS-LV,r=0.25,p=0.0004）and Du Paul ADHD Rating Scale IV（ADHD-RS,r=0.18,p=0.03）.Finally,we found that when sample size came to 252,the results of ADHD-related pattern were relatively reliable.Similarly,the sample size needed to be 162 when explore the relationship between ADHD-related pattern and behavioral indicator measured by CPRS-LV.In the second study,we used a nested-spectral partition（NSP）to identify the functional abnormality of the ADHD related pattern constructed in the first study with145 ADHD patients（age:11.07±2.03）and 135 TDC（age:11.11±1.69）.We firstly identified the segregation and integration of the attention network and explored the effect of subtype（ADHD-C and ADHD-I）and sex on segregation and integration in children with ADHD.Then,the relationship between hierarchical segregation and integration of ADHD related pattern and inattention symptom was also investigated.Our results demonstrated that:1)children with ADHD had lower segregation(p=1.17×10^-8,Cohen’s d=-0.70)of the ADHD related pattern than TDC;2)a lower segregation component was existed in both ADHD-C and ADHD-I patients and the effect size of abnormalities of mean segregation component of different ADHD subtypes demonstrated ADHD-I（Cohen’s d=-0.70）>ADHD-C（Cohen’s d=-0.65）;3)the segregation components in the ADHD related pattern were negatively related to inattention scores measured by CPRS-LV（r=-0.24,p=0.002）and ADHD-RS（r=-0.21,p=0.03）.