Traditional diagnostic criteria such as the DSM and ICD have limitations in capturing the complexity of mental disorders, including the spectrum and heterogeneity of symptoms. In recent years, the transdiagnostic model based on the Research Domain Criteria (RDoC) framework has been increasingly applied to clinical research on child and adolescent mental disorders. This model facilitates a deeper understanding of the underlying pathological mechanism, supports the prevention of disease onset and progression, and informs the development of transdiagnostic treatment approaches.

Objective To analyze the differences in cerebral blood flow(CBF)characteristics among children with different subtypes of attention deficit and hyperactivity disorder(ADHD)and their relationship with executive function using arterial spin labeling(ASL)technology.Methods A case-control study was conducted,including children diagnosed with ADHD at the outpatient clinic of Peking University Sixth Hospital from July 2015 to December 2019 as the ADHD group,and typically developing schoolchildren from January to December 2021 as the healthy control group.Both groups underwent pseudo-continuous ASL(pCASL)scanning to measure CBF,and executive function was assessed using the parent version of the Behavior Rating Inventory of Executive Function(BRIEF).Differences in CBF between ADHD children and healthy controls were com-pared.For brain regions showing significant group differences,CBF values were extracted and linear regression models were constructed with BRIEF scores to further explore the relationship between regional CBF and execu-tive function.Results A total of 134 boys with ADHD were included[83 with ADHD predominantly inat-tentive subtype(ADHD-Ⅰ)and 51 with ADHD combined subtype(ADHD-C)],along with 25 healthy control boys.Intergroup comparisons revealed that the CBF in the left middle temporal gyrus was significantly lower in ADHD-C children compared to both ADHD-Ⅰ children(P=0.010)and healthy controls(P＜0.001),while no significant difference was observed between ADHD-Ⅰ children and healthy controls(P=0.280).After adjusting for age and total IQ scores,the linear regression model showed that the CBF in the left middle temporal gyrus of ADHD-C children was negatively correlated with the planning/organization score on the BRIEF(β=-0.062,P=0.030).Conclusions The CBF in the left middle temporal gyrus of boys with ADHD-C is significantly lower than that of boys with ADHD-Ⅰ and healthy controls.This reduced regional CBF may be associated with executive function deficits in organization and planning abilities in ADHD-C,providing new insights into the neurobiological mechanisms underlying ADHD subtypes.

Objective:To investigate the association between prenatal environmental factors and attention defi-cit hyperactivity disorder(ADHD)and its symptom severity in children.Methods:Based on the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition(DSM-Ⅳ)diagnosis criteria,1 156 children with ADHD and 289 normal control children were included in this study.ADHD diagnoses were established using the Clinical Diag-nostic Interview Scale,core symptoms were assessed with the ADHD Rating Scale,and information on prenatal ex-posures were collected via self-developed questionnaires.Results:Maternal stress during pregnancy was associated with increased risk factor of ADHD in children(OR=1.22,P＜0.01).Among children with ADHD,preconception paternal alcohol consumption was positively associated with hyperactivity/impulsivity symptoms(β=0.08,P＜0.05),and maternal smoking during pregnancy was positively associated with total symptoms(β=0.07-0.09,P＜0.05).Conclusion:Maternal stress during pregnancy may increase the risk factor of ADHD in children.Both pre-conception paternal alcohol consumption and maternal smoking during pregnancy may be associated with increased ADHD symptom severity in children.

Traditional diagnostic criteria such as the DSM and ICD have limitations in capturing the complexity of mental disorders, including the spectrum and heterogeneity of symptoms. In recent years, the transdiagnostic model based on the Research Domain Criteria (RDoC) framework has been increasingly applied to clinical research on child and adolescent mental disorders. This model facilitates a deeper understanding of the underlying pathological mechanism, supports the prevention of disease onset and progression, and informs the development of transdiagnostic treatment approaches.

Objective:To explore the impulsivity characteristics of patients with attention deficit hyperactivity disorder(ADHD)comorbid with borderline personality disorder(BPD)and the mediating role of emotion regula-tion strategies.Methods:A total of 96 patients with ADHD meeting the diagnostic criteria of the American Diagnos-tic and Statistical Manual of Mental Disorders,Fourth Edition(DSM-Ⅳ)were enrolled,48 of whom had comorbid BPD.Impulsivity was assessed with the Barratt Impulse Scale(BIS)and the impulse control difficulty dimensions of Emotional Regulation Difficulty Scale(DERS).Emotion regulation strategies were evaluated with the Emotion Regulation Questionnaire(ERQ).Results:No significant differences were found between the ADHD with and with-out BPD group in cognitive impulsivity,motor impulsivity,or non-planning impulsivity as assessed with the BIS(Ps＞0.05).However,the ADHD with BPD group showed higher scores on the DERS impulse control difficulty subscale(P＜0.001)and less frequent use of cognitive reappraisal strategies(P＜0.001).Cognitive reappraisal partially mediated the relationship between ADHD with BPD and impulse control difficulties,with an effect size of 25.9％.Conclusion:ADHD patients comorbid with BPD exhibit heightened emotional impulsivity,which might be partially mediated by reduced use of cognitive reappraisal.

Objective:To explore the impulsivity characteristics of patients with attention deficit hyperactivity disorder(ADHD)comorbid with borderline personality disorder(BPD)and the mediating role of emotion regula-tion strategies.Methods:A total of 96 patients with ADHD meeting the diagnostic criteria of the American Diagnos-tic and Statistical Manual of Mental Disorders,Fourth Edition(DSM-Ⅳ)were enrolled,48 of whom had comorbid BPD.Impulsivity was assessed with the Barratt Impulse Scale(BIS)and the impulse control difficulty dimensions of Emotional Regulation Difficulty Scale(DERS).Emotion regulation strategies were evaluated with the Emotion Regulation Questionnaire(ERQ).Results:No significant differences were found between the ADHD with and with-out BPD group in cognitive impulsivity,motor impulsivity,or non-planning impulsivity as assessed with the BIS(Ps＞0.05).However,the ADHD with BPD group showed higher scores on the DERS impulse control difficulty subscale(P＜0.001)and less frequent use of cognitive reappraisal strategies(P＜0.001).Cognitive reappraisal partially mediated the relationship between ADHD with BPD and impulse control difficulties,with an effect size of 25.9％.Conclusion:ADHD patients comorbid with BPD exhibit heightened emotional impulsivity,which might be partially mediated by reduced use of cognitive reappraisal.

Objective:To investigate the association between prenatal environmental factors and attention defi-cit hyperactivity disorder(ADHD)and its symptom severity in children.Methods:Based on the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition(DSM-Ⅳ)diagnosis criteria,1 156 children with ADHD and 289 normal control children were included in this study.ADHD diagnoses were established using the Clinical Diag-nostic Interview Scale,core symptoms were assessed with the ADHD Rating Scale,and information on prenatal ex-posures were collected via self-developed questionnaires.Results:Maternal stress during pregnancy was associated with increased risk factor of ADHD in children(OR=1.22,P＜0.01).Among children with ADHD,preconception paternal alcohol consumption was positively associated with hyperactivity/impulsivity symptoms(β=0.08,P＜0.05),and maternal smoking during pregnancy was positively associated with total symptoms(β=0.07-0.09,P＜0.05).Conclusion:Maternal stress during pregnancy may increase the risk factor of ADHD in children.Both pre-conception paternal alcohol consumption and maternal smoking during pregnancy may be associated with increased ADHD symptom severity in children.

Objective:To investigate the associations between several single nucleotide polymorphisms (SNPs) at BAIAP2 with executive functions in patients with attention deficit/hyperactivity disorder (ADHD) and in healthy control subjects. To investigate if these associations are sex-specific and/or subtype-specific. Methods:A total of 929 Han Chinese youths with DSM-Ⅳ ADHD were recruited from the outpatient department of Peking University Sixth Hospital from May 2005 to January 2011, and 161 unaffected controls were recruited from the primary and secondary schools in Beijing from January 2005 to January 2010. All subjects were rated for the clinical information and executive functions based on laboratory examinations, such as inhibition, working memory, and set shifting. Four SNPs of BAIAP2 were chosen and genotyped using TaqMan TM real-time PCR assays. Analysis of covariance (ANCOVA) were conducted, with gender, age and IQ as covariates, to compare executive functions between children with ADHD and normal controls, and to explore the association of BAIAP2 SNPs with executive functions of ADHD subjects (total samples and sex/subtype stratified samples) and unaffected controls. Results:Compared to unaffected controls, children with ADHD performed significantly worse in inhibition ( F=11.64, 26.50, P≤0.001) and set shifting ( F=25.68, P<0.001). In unaffected controls, there was no correlation between any BAIAP2 SNPs and executive functions. In ADHD cases, rs4969239 was significantly associated with set shifting times, with G allele carriers used longer time than others and had a worse set shifting function (B=-17.55, F=7.13, P=0.008), and rs9901648 was significantly associated with color interference time, with AA genotype carriers used longer time than others and had a worse inhibition function (B=1.82, F=8.84, P=0.003). In further analysis, the association between rs9901648 and color interference only existed in male participants with ADHD ( F=11.33, P=0.001). Conclusions:BAIAP2 gene possibly contributes to the set shifting and inhibition impairment in children with ADHD, but not in unaffected controls. In addition, the association between BAIAP2 gene and inhibition mainly exists in male children with ADHD.

Objective:This study explores the relationship between emotional dysregulation, attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms using network models.Method:A total of 967 children with ADHD comorbid ODD were recruited from the outpatient department of Peking University Sixth Hospital from September 2002 to June 2022. All subjects were rated for the ADHD symptom severity using the ADHD symptom rating scale. ODD symptoms and emotional dysregulation symptoms were assessed by the Children′s Clinical Diagnostic Interview Scale, and the Conners′ Parent Symptom Questionnaire. R (version 4.2.1) packages mgm, qgraph, bnlearn, etc. were used for network analysis, and centrality indices were calculated to define central symptoms and bridge symptoms. Results:The relationship between emotional dysregulation and ODD symptoms was closer. ODD symptoms had higher strength indices, especially the items "gets annoyed or irritated by the behavior of adults"(strength=3.57) and "loses temper or gets angry with adults when does not get his or her own way"(strength=2.32). Emotional dysregulation symptoms had a higher bridge strength indices, with "temper outbursts, explosive and unpredictable behavior" (bridge strength=2.64) as the most prominent item. Bayesian network analysis showed that ADHD symptoms were at the upper of DAG, directly linked with emotional dysregulation symptoms and indirectly linked with ODD symptoms through emotional dysregulation symptoms.Conclusion:Emotional dysregulation symptoms were more closely associated with ODD symptoms than ADHD symptoms, and might potentially acted as bridge symptoms between ADHD and ODD. ADHD symptoms might drive ODD symptoms indirectly through emotional dysregulation symptoms.

Objective:To investigate the characteristics of cortical morphology in children with attention defi-cit hyperactivity disorder(ADHD)and those with oppositional defiant disorder(ODD)from both categorical and dimensional analyses.Methods:A total of 72 children were enrolled,including 16 children with ADHD and ODD,20 children with ADHD without ODD,and 36 age-gender-matched normal children.The diagnoses were made ac-cording to the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition(DSM-Ⅳ)criteria.The Chi-nese Wechsler Intelligence Scale for Children(C-WISC)was used to access intelligence quotient.All subjects par-ticipated in the magnetic resonance imaging(MRI)scan.The features of cortical morphology were determined using FreeSurfer software.Results:Children with ADHD and ODD[(6 528.1±857.5)mm3 vs.(7 591.2±657.3)]and children with ADHD only[(6 867.2±41.3)mm3 vs.(7 591.2±657.3)mm3]had smaller volume in the left later-al superior temporal gyrus(P＜0.05)than controls.No difference was found between ADHD with ODD group and ADHD without ODD group.There was no correlation between the cortical volume of left lateral superior temporal gyrus and ODD symptoms.Conclusion:The reduced cortical volume of left lateral superior temporal gyrus may be an important indication of the abnormal brain structure of ADHD in children.And comorbid status of ODD dose not change this structural variation.